BIBLIOGRAPHY SAGALLA, ESTHER JOSEPHINE D....
BIBLIOGRAPHY
SAGALLA, ESTHER JOSEPHINE D. APRIL 2007. Chipping Quality of Potato
Accessions Grown Organically in Different Production Sites in Benguet. Benguet State
University, La Trinidad, Benguet.
Adviser: Belinda A. Tad-awan, Ph.D.
ABSTRACT
The chipping quality of nine potato accessions grown organically in different
production sites of Benguet was evaluated. The study aimed to determine the influence of
different production sites on the chipping quality of potato accessions grown organically,
identify the potato accession with the best chipping quality, and determine the interaction
between the production site and potato accession on chipping quality.
Potatoes grown in Balili, La Trinidad (1,336 m asl; 18.360C; 71.81% RH) had
relatively high yields and consistently produced tubers with good chip quality.
Furthermore, the harvested potatoes had high dry matter content (20.78%), specific
gravity (1.077), and chip recovery (82.74%). The potatoes also had one of the lowest
sugar content (3.940Brix), thus, producing light yellow chips with no browning. The
chips were also liked much by the panelists.
Potatoes harvested from Longlong (1,342 m asl; 20.490C; 80.81% RH) and
Cabutotan (1,588 m asl; 16.190C; 87.50% RH) also yielded well with a good chipping
quality and high chip recovery. Moreover, the chips produced were light yellow but were
liked moderately by panelists.
Accession 13.1.1 and 5.19.2.2 had the highest dry matter contents (20.03% and
20.47%), specific gravity measurements (1.074 and 1.084), and percent chip recovery
(78.07 and 77.57). Also, they had the lowest sugar contents (3.880Brix and 3.910Brix),
thus, producing the desired light yellow chips with no browning.
Production site and potato accession interacted significantly to affect dry matter
content, sugar content, chip recovery, chip color, and specific gravity. This interaction
means that both site and accession are important considerations in organic growing of
potatoes for chipping.
ii
TABLE OF CONTENTS
Page Number
Bibliography …….………………………………………………….
i
Abstract …………………………………………………………….
i
Table of Contents …………………………………………………..
iii
INTRODUCTION ………………………………………………….
1
REVIEW OF LITERATURE ………………………………………
5
MATERIALS AND METHODS …………………………………..
16
RESULTS AND DISCUSSION
Cultural Management Practices for Organic
Potato Production in Different Production
Sites ………………………………………………………...
26
Temperature and Relative Humidity in the
Different Production Sites ………………………………….
37
Soil Properties in the Different Production
Sites …………………………………………………………
38
Total Yield ………………………………………………….
43
Tuber Characteristics ……………………………………….
47
Dry Matter Content …………………………………………
56
Specific Gravity …………………………………………….
61
Sugar Content ……………………………………………….
65
Chip Recovery ………………………………………………
69
Chip Color …………………………………………………..
73
Chip Browning ………………………………………………
76
Sensory Evaluation ………………………………………….
78
iii
SUMMARY, CONCLUSIONS, AND
RECOMMENDATIONS
Summary
……………………………………………………. 82
Conclusions
…………………………………………………. 84
Recommendations
…………………………………………... 85
LITERATURE CITED ………………………………………………
86
APPENDICES ……………………………………………………….
91
BIOGRAPHICAL SKETCH ………………………………………...
115
iv
1
INTRODUCTION
Background of the Study
Potato varieties with high yield and acceptable processing quality are vital
requisites in our local processing industries. However, varieties with such
characteristics are limited. Only a few processing varieties such as Igorota,
Kennebec, Atlantic, and Columbus are grown in the highlands. Thus, there is an
increasing need to continuously evaluate more varieties or accessions that have
good processing qualities.
One of the processed products set for commercial production is the potato
chip. The chips first appeared during the mid 1850’s as a normal part of American
cooking. The potato was most likely sliced from the axis of the tuber and then
fried. It was only until a certain chef named George Crum sliced the tubers thin
enough to become crunchy potato chips. The chips, originally called ‘potato
crunches’ became popular in restaurants and grocery stores. They were eventually
introduced to England and neighboring countries during the early to mid part of
the 20th century (Harmon, 1998).
The potato chip industry continues to grow in countries worldwide
including the Philippines. In fact, 400 to 533 metric tons of fresh potato tubers
must be supplied merely for potato chip processing (Department of Agriculture et
al., undated). However, with the reported Philippine production of 68,000 metric
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
2
tons (FAO, 2002), only a portion of it is usually suitable for processing.
The Philippine government thus imports processed potatoes, which in 2001 were
valued at $16,858,000.00 (Gagnon, 2002).
Importance of the Study
Potato processors use whatever is available to them at the time of
processing. Some processors use a mixture of potato varieties which are both
imported and locally produced. As a result, the quality of potato chips is greatly
affected. For instance, potato varieties with high sugar content produce brown
chips with bitter taste. Other varieties with low dry matter content produce soggy
potato chips with high oil uptake and longer frying time.
Furthermore, two large-scale potato processors in Metro Manila mainly
procure the Granola variety because it is readily available but not ideal for
processing. It has low dry matter, high moisture content, and produces chips that
easily brown during frying (FRLD, 1995)
Potatoes are mainly grown conventionally with the application of
expensive chemicals and other synthetic compounds. When chipped, these
potatoes were found to contain as high as 73% pesticide residue (Lang, 2005).
Growing processing type potatoes organically is therefore a better alternative to
conventional production methods. It is in fact claimed that organically grown
potatoes taste better and contain more dry matter than conventionally-grown ones
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
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(Finesilver, 1980). Health wise, organically grown potatoes are safe foods that are
free from toxic and harmful chemicals.
The location of production areas and the employed cultivation practices
also influence important quality factors of potato tubers for processing such as
specific gravity, dry matter, sugar content, and others. Thus, it is necessary to
grow potatoes in several locations to evaluate processing quality of different
accessions.
Several studies have been conducted to evaluate the suitability of potato
varieties to chipping. However, the varieties identified for processing are limited
and often susceptible to diseases.
It is therefore important not only to identify an appropriate potato
accession that can give good quality chips but also determine the effect of
location of production to potato chip quality.
Objectives of the Study
The objectives of this study were to:
1. determine the effect of different production sites on the chipping
quality of potato accessions grown organically;
2. identify the potato accession grown organically with the best chipping
quality across production sites; and
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
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3. determine the interaction of the potato accessions and different
production sites on chipping quality.
Time and Place of the Study
The study was conducted at Englandad, Sinipsip, Loo, Balili, Longlong,
and Cabutotan where the potatoes were organically grown. The harvested
potatoes were processed at the College of Agriculture Complex, Benguet State
University, La Trinidad.
The study was conducted from October 2005 to March 2006.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
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REVIEW OF LITERATURE
Origin and Distribution of Potato Chips
Piecing together how chips spread between 1853 and the early part of the
20th century is difficult. It is, however, assumed that the potato chips first
appeared in 1853 at Saratoga Springs, New York, which is considered its place of
origin. A certain cook named George Crum sliced the tubers very thinly to
produce crispy potato chips. The potato chips were then introduced to England in
1921 (Harmon, 1998) and eventually to other parts of the world.
The Potato Chip Industry
The potato chip industry has a demand for fresh potato up to 533 MT
daily. However, this demand for potatoes intended for processing is not met by
local production in volume and quality (HARRDEC, 1998).
Baguio and Benguet are the primary suppliers of potatoes for chips in the
Philippines. A newly emerging supplier is Mindanao. Metro Manila has been
absorbing about 50% of the potato chips. However, sales of potato chips in the
Philippines declined from 14% in 1990 to 6% in 1992 (Dep’t of Agriculture,
undated).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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Suitability of Potato Varieties for Chipping
Production
and
yield. Planting area and production of processing are very
limited. The main reasons are lack of suitable varieties for processing, little access
of potato farmers to these varieties, limited knowledge of industries on the
standards and requirements of processing potatoes, and susceptibility of
processing varieties to pest and diseases (Kaiyun et al., 2004).
High tuber yields and quality are also important determinants for the
suitability of a given variety for large-scale local production. Varieties with higher
specific gravity and dry matter tend to have higher yields and better quality of
finished chips. Moreover, color of chips depends on sugar content of tubers
(Tawfik et al., 2002).
Well-adapted potato cultivars that require fewer days to produce high
marketable yields would be specifically advantageous in much of the East. Unlike
most western production areas, short seasons (90-110 days) prevail in much of the
East, especially in northern areas. Early-maturing cultivars would also be useful
in intensively managed systems (e.g. organic, hoop houses, etc), especially if
access to the earliest markets and/or escape from persistent disease and insect
pressure (NERA, 2002).
Available varieties. Choosing varieties is very important for chip
processing, however, small-scale producers use varieties that are available to them
at the time of processing. As a result, the quality of chips varies tremendously, as
Chipping Quality of Potato Accessions Grown Organically in Different Production
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the processing quality is a function of both physical and chemical factors of the
tubers (Illeperuma and Wickramasinghe, 2000).
Moreover, potato varieties for processing suffer from poor varietal
improvement (Dep’t of Agriculture, undated).
Locally
grown
potato
varieties in the country have very low dry matter content (15% to 18%) which is
not suitable for processing. The development of suitable varieties (i.e. adapted to
the local growing conditions and acceptable to processors and consumers) is
therefore very necessary not only to help local farmers but also to develop the
country’s potato processing industry (HARRDEC, 1998).
Several potato varieties have been identified to be adaptable to the
country’s agro-climatic conditions such as the Chipeta and Atlantic for chips, and
the Kennebec and Century Russet for both chips and fries. These varieties are now
being tested in various experimental farms in the Cordillera and in the growing
areas of Mindanao (Department of Agriculture, undated).
Dry matter content and specific gravity. Potato varieties with high dry
matter content are considered suitable for chips as the dry matter content is
associated with mealiness, crispness, and reduced oil uptake in the fried chips
(Illeperuma and Wickramasinghe, 2000).
Potato varieties for chipping has to have high dry matter content (19% and
above). High dry matter content gives high chip yield with low fat content.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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Further, to obtain light colored chips, the reducing sugar content should be less
than 0.2% (NPRCRTC, undated).
For the production of potato chips, varieties with dry matter content of 22-
24% are required. The content of reducing sugars in the potato is also a
determining factor with respect to the suitability of a potato variety for
processing. Usually, the lower the reducing sugar content, the better the quality of
the product. Potato varieties with 0.2% reducing sugar are acceptable for chips
(Coumou, 1991).
The specific gravity or the dry matter content of potatoes are important
because it influences the uptake of fat or oil during frying. Higher yield of
processed products and lower oil uptake is a result of potatoes with high specific
gravity (Verma, 1991).
High specific gravity is particularly important in the production of potato
varieties for chips because of greater surface area to volume ratio in chips.
Moreover, chip crispiness and lack of oiliness increases with increasing specific
gravity (Scanlon, 2006).
Sugar
content. Processors prefer varieties that are best suited to produce
light colored chips. However, maintenance of the desired color is the major
problem associated with the chipping industry. The varieties used have inherent
differences with respect to their chip color. These varieties contain different levels
of reducing sugar, which are used to predict the suitability of potato tubers for
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
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chip processing, as they are often responsible for color development (Illeperuma
and Wickramasinghe, 2000).
A reducing sugar content of 0.25 to 0.30 mg-g^sup-1^ fresh weight or
0.025% to 0.030% on fresh weight basis is the maximum concentration allowed in
tubers used for chips (Oltmans and Novy, 2002).
Potatoes destined for making chips, French fries and other fried products,
need to have low sugar content to avoid browning of the finished product. The
sugar content of potatoes is determined by the genotype and several pre and post-
harvest factors (Kumar et al., 2004).
Morphological
characters. Potato chipping varieties should have round
and uniform tuber shape, light brown tuber skin color, shallow eye depth, and free
from defects. Moreover, these varieties must have low reducing sugar (< 0.2%)
and moderate dry matter content (20-25%) (Kaiyun, 2004).
Large round tubers are preferred by the chipper, since their size and shape
facilitate the removal of the peel more efficiently and with less solid loss. Further,
cultivars with shallow eyes and few in number are to be preferred. If the eyes are
deep, it is necessary to peel for longer periods of time to remove the eye. Potato
varieties with high specific gravity are also preferred because they have been
shown to absorb less cooking oil during the chipping process (Gould, 1988).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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Potato Chip Quality
Good quality potato chips have a light color with little vascular
discoloration. The color of potato chips depends on the reducing sugar content of
the potatoes. Potato chips must also have a pleasing and desirable flavor, thus
potatoes used in chipping must not be bitter or have other off-flavors. The flavor
of potato chips is more complex than that of boiled, baked or mashed potatoes,
since the cooking temperatures are higher, and the absorbed oil contributes to the
overall flavor profile of the product (Scanlon, 2006).
An important factor influencing potato chip color is the level of reducing
sugars, glucose and fructose, at the time of frying. Glucose and fructose are the
products of sucrose hydrolysis mediated by the enzyme invertase. Increasing
concentrations of reducing sugars in the tuber correlate with darker chip color
(Oltmans and Novy, 2002).
Chipping quality is a genetically transmissible character. Potatoes that
produced light-colored chips after cold storage and reconditioning were shown to
transmit the ability to produce light-colored chips to their progenies (Oltmans and
Novy, 2002).
Many factors contribute to potato chip quality. This includes maturity of
tuber, shape, thickness, skin, peel, eyes, skin and flesh color, defects, specific
gravity, temperature, reducing sugar and sucrose content, and chipability. Chip
manufacturing procedures, such as peeling, slice thickness and uniformity, oil
Chipping Quality of Potato Accessions Grown Organically in Different Production
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type and temperature and packaging methods and materials all have a direct
impact on potato chip quality (Ohio State University, 2002).
The quality of chips is determined by appearance, color, taste/ flavor,
texture, moisture content, oil content and nutritional value. Color is by far the
most important quality characteristic followed by oil content (Hesen, 1991).
Influence of Production Site to Processing Quality of Potatoes
Experiments have shown a high effect of the factor “site” on the suitability
for processing of different potato varieties in organic farming. The results of these
experiments confirm the influence of site of production on the quality of potatoes
for processing (FAL, 2005).
The sugar content of potatoes is affected by the climatic factors in a
location, such as temperature during growth, minimal nutrition, and irrigation
(Kumar et al., 2004).
The amount of sucrose found in potatoes at harvest is influenced by
planting date, growing location, soil fertility, water availability, and any stress-
inducing event (Campbell and Bagley, 2006).
Specific gravity of tubers is influenced by the cultural management of
farmers in a location. Specific gravity generally decreases with reduced water
application and increased available nitrogen (Ojala et al, 1990).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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The variation in specific gravity, yield and percent yield of large size
tubers may be caused by cultivation practice, climatic condition, time of planting
and harvesting, location, etc. Hence, it is necessary to grow the selected clones at
several locations for further evaluation of processing quality, specific gravity,
yield, and percent yield of large size tubers (Tantidham et al., 1991).
Both the specific gravity and the dry matter content varied with the variety
and the location of production. Such variation has been reported for many
varieties grown in other countries (Verma, 1991).
Organic Farming in Potatoes
Varietal
selection. In selecting varieties for organic potato production,
varieties suited to organic production and those which best suit the intended
market should be selected and grown (Dep’t of Agriculture for Northern Ireland,
1996).
Crop
rotation. Potato plants are easy to grow, but they aren’t the easiest to
grow using organic methods. Potatoes are prone to quite a few insect pests and
diseases that can be a challenge to manage organically (Grubinger, 2005). Thus,
organic potatoes must be a part of an overall rotation. This will involve building
up of soil fertility and then exploiting that fertility with a nutrient-demanding crop
such as potatoes. Legumes must be included in the rotation to provide nitrogen.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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Without adequate nitrogen being available, the potato crop will yield very poorly
(Walsh, 2001).
Fertilizer
application. Potato growth depends on a supply of plant
nutrients, such as nitrogen, phosphorus, and potassium. Each of these nutrients
has specific functions for the growth and development of potato plants (Vander
Zaag, 1981). Based on the results of some studies, combined potassium (K) and
organic nitrogen (N) was found to be the most efficient fertilizer to increase yield
for crisp and french fry production (Haase, 2005).
Quality of Organically Grown Potatoes
Organically grown foods provide more nutrients than conventionally
grown foods. A recent study conducted by the Organic Center for Education and
Promotion found that organically grown foods contained on average 30% more
antioxidants than their conventional counterparts. A higher intake of antioxidants
has been shown to have a protective effect against development of cancer,
coronary heart disease, and cataracts (Lang, 2005).
In addition, glycoalkaloids (natural protective agents in potato plants and
tubers) and levels of potassium, magnesium, phosphorus, and sulfur were found to
be higher in organic potatoes (Martin, 2005). Vitamin C may be higher as well in
organically grown produce (Finesilver, 1989).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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Organically grown food also has higher dry matter content with a small
number of results showing them to be lower (Finesilver, 1989).
In terms of taste, potatoes grown organically obtained significantly higher
mean taste scores than conventionally grown after 6 months storage when tested
blindly by a panel (Finesilver, 1989). This difference may be explained by the
presence of glycoalkaloids which are higher in organic potatoes. Glycoalkaloids
are thought to move from outer (such as skin) to inner (such as flesh) layers of
potatoes during boiling and responsible for the perceived flavor differences
(Martin, 2005).
Comparison between Conventional and Organically Grown Potatoes
Fertilizer
application. Conventional fertilizing practices such as increased
application of synthetic N fertilizers may possibly result in higher crude protein
concentration in plant foods but poorer quality protein than organic practices
(Finesilver, 1989).
Pesticide
residue. Organically grown foods have fewer pesticide residues
than conventionally grown foods. Pesticide residues were found on 23% of
organic foods and 73% of conventional foods. When incidences of DDT and other
banned pesticides were removed, the incidence on organically grown foods fell to
13%, but only to 71% on the conventional crops. This result indicates that roughly
half of the incidence of residue found on organically grown foods is due to the
Chipping Quality of Potato Accessions Grown Organically in Different Production
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persistence of past pesticide use. The incidences of residue found on
conventionally grown produce were due to current applications (Lang, 2005).
Yield. Yields on organic farms are found to be lower than yields on
conventional farms, in large part because of damage by insects and diseases, but
profits are higher because organic potato prices are higher than conventional
prices. However, even with the price premium, good organic growing practices
are needed in order to assure decent marketable yields (Grubinger, 2005).
Organically grown products are on the average 57% more expensive than
conventionally grown ones. However, the higher cost is balanced by the benefits
of organically grown foods (Lang, 2005).
Statistical Tool Used to Analyze Sensory Evaluation of Processed Products
Data of sensory evaluation for chips and French fries were statistically
analyzed using a General Linear Model (GLM) procedure of SAS Institute. Least
Significant Difference (LSD) at P < 0.05 was used to separate treatment means
(Tawfik et al., 2002).
Computation of data for chip color was carried out using the multiple
linear regression analysis program (32 regression). The results of this computation
(coefficient of multiple correlation and regression equation) indicate that these
equations provide reasonably good prediction of the chip color of individual
potato cultivars (Mazza, 1983).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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MATERIALS AND METHODS
Nine potato accessions obtained from Northern Philippine Root Crop
Research and Training Center (NPRCRTC) were planted in different production
sites of Benguet and their tubers were processed as chips.
The treatments of the study replicated three times were:
Factor A: Production Sites (PS)
Place
Elevation
PS
1
Englandad,
Atok
2,
300
m
PS 2
Longlong, La Trinidad
1, 342 m
PS 3
Sinipsip, Buguias
2, 350 m
PS
4
Loo,
Buguias
1,
638
m
PS 5
Balili, La Trinidad
1, 336 m
PS
6
Cabutotan,
Madaymen 1,
588
m
Factor B: Potato Accessions (NOP)
Agency Code
NOP
1
380251.17
NOP
2
676070
NOP
3
Ganza
NOP
4
285411.22
NOP
5
573275
Chipping Quality of Potato Accessions Grown Organically in Different Production
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NOP
6
676089
NOP
7
5.19.2.2
NOP
8
575003
NOP
9
13.1.1
Experiment 1: Field evaluation of potato
accessions in different production sites
Nine potato accessions were planted in six organic farms of Benguet.
Rooted stem cuttings were used in all sites. The cuttings were planted in 1m x 5 m
beds at 30 cm between hills and rows in all sites except Longlong. The cuttings
were instead planted in plastic pots situated in partially shaded plastic houses.
Cultural management practices for organic production such as multiple
cropping, use of yellow traps, planting of repellant crops, and others were
followed in each site.
The potato accessions were then harvested and samples of mature and
sound potato tubers were obtained from the different sites.
The treatments in each site were laid out following randomized complete
block design (RCBD).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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The data gathered were:
1. Organic production practices of farmers. The farmers from each
location were interviewed using a prepared questionnaire to determine their
specific organic production practices that might affect chip quality.
2. Site description. The relative humidity, temperature, soil properties,
and elevation of the different production sites were taken.
3. Total yield/ accession (g/ plant). This was obtained by taking the total
weight of tubers from each treatment at harvest.
Experiment 2: Processing quality of potato accessions
grown in different production sites
Medium to large-sized potato tubers were weighed at 100 g per replication
per treatment. The tubers were then hand peeled, sliced into approximately 1 mm
thickness using a chipper and washed thoroughly with water (Plate 1). To reduce
oil absorption, the chips were drained on a cotton cloth. The potato chips were
deep-fried in vegetable oil and drained when bubbling of oil stopped and were
packed and sealed in polyethylene bags for sensory evaluation by ten non-
smoking panelists.
The treatments were laid out using the 9 x 6 factor factorial in randomized
complete block design (RCBD) with three replications.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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a. Chipping of potato tubers
b. Drying of potato chips
c.
Frying of potato chips
d. Packing of potato chips for sensory evaluation
Plate 1. Chipping of the different potato accessions
Chipping Quality of Potato Accessions Grown Organically in Different Production
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The data gathered were:
1. Tuber characteristics. The shape, peel color, peel texture, flesh color,
eye depth, and other characters were taken using the following scales (CIP, 1977):
a. Tuber skin color.
Rate
Description
0
White-cream
1
Yellow
2
Orange
3
Brownish
4
Pink
5
Red
6
Purplish-red
7
Purple
8
Dark purple-black
b. Tuber skin type
Rate
Description
0
Smooth
1
Rough (Flaky)
2
Partially netted
3
Totally netted
4
Very heavily netted
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c. Tuber flesh color.
Rate
Description
0
White
1
Cream
2
Pale yellow
3
Yellow
4
Deep Yellow
5
Red
6
Violet
7
Purple
d. General tuber shape
Rate
Description
0
Compressed
1
Round
2
Ovate
3
Obovate
4
Elliptic
5
Oblong
6
Long-oblong
7
Elongate
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e. Depth of tuber eyes
Rate
Description
0
Protruding
1
Shallow
2
Medium
3
Deep
4
Very deep
2. Dry matter content (%). Twenty gram samples of potato tubers were
sliced into cubes, weighed, and ovendried (Memmert D-91126 Schwabach) at
800C for 24 hours. The dry matter content was then be computed using the
formula:
Dry matter content = 100% - % Moisture content
Where:
Fresh weight – Ovendry weight
% Moisture content =
x 100
Fresh
weight
3. Specific gravity. The dry matter content of the tubers was converted
into specific gravity measurement using a table of equivalents (Kellock, 1995).
4. Sugar content (0Brix). Juice was extracted from grated potato tubers.
The sugar content from the extracted juice was then taken using a digital
refractometer (Atago USA, Inc.).
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5. Chip recovery (%). The weight of unpeeled and chipped tubers was
taken and chip recovery was computed using the formula:
Weight of unpeeled tubers–Weight of chipped potatoes
Chip recovery =
x 100
Weight of unpeeled tubers
6. Chip color. Potato chip color was determined using the Potato Chip
Color Reference Standard prepared by the Potato Chip Institute International
(undated).
7. Chip browning. The browning of the chips was evaluated using the
following scale:
Scale
Description
1
No browning
2
Slight browning
3
Moderate browning
4
Severe browning
8. Sensory evaluation. The crispiness, flavor, texture, oiliness,
appearance, and general acceptability of the potato chips were evaluated by ten
panelists using the following rating scales:
a. Crispiness (Jose, 1998)
Scale
Description
Remarks
1
Very easy to crumble
Very crispy
2
Easy to crumble
Crispy
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3
Crumbled without difficulty Moderately crispy
4
Crumbled with difficulty
Slightly crispy
5
Hard to crumble
Not crispy
b. Flavor (Jose, 1998)
Scale
Remarks
Description
1
Very strong flavor
Very perceptible
2
Strong flavor
Perceptible
3
Little flavor
Moderately perceptible
4
Very little flavor
Slightly perceptible
5
No flavor
Not perceptible
c. Texture (Jose, 1998)
Scale
Description
1
Firm
2
Moderately Firm
3
Slightly Firm
4
Not Firm
d. Oiliness
Scale
Description
1
Very oily
2
Oily
3
Moderately oily
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
25
4
Slightly oily
5
Not oily
e. Appearance
Scale
Description
1
Like very much
2
Like much
3
Like moderately
4
Like slightly
5
Not like/ Dislike
f. General acceptability
Scale
Description
5
Like very much
6
Like much
7
Like moderately
8
Like slightly
9
Not like/ Dislike
The data was analyzed through Analysis of Variance using the 9 x 6 factor
factorial in RCBD across sites. The significance among treatment means was
analyzed using Duncan’s Multiple Range Test (DMRT).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
26
RESULTS AND DISCUSSION
Experiment 1: Field Evaluation of Potato
accessions in Different Production Sites
Cultural Management Practices for Organic Potato
Production in the Different Production Sites
Applying the appropriate cultural management practices in growing
potatoes for processing is important. Such practices could affect chip quality
(Table 1).
Englandad, Atok
Description of the farm. The farm is located at 2,300 m asl on a plateau. It
has been cultivated organically for four years and previously planted with
vegetables such as carrot, broccoli, cabbage, etc. Calla lily is also planted as
borders and windbreakers.
Cropping
pattern. Rotation of carrot (or cabbage, Chinese cabbage, etc.),
potato, and carrot is a common practice in the farm. Oftentimes, potato is also
planted at the same time with other crops such as brocolli. Garden pea, pechay, or
sweetpotato is planted on the borders of the farm.
Land
preparation. The common practices such as cleaning, digging, and
making of raised beds are done with the use of grab hoe and sharp wooden stick.
Before sowing, the soil is pulverized for more efficient root growth.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
27
Table 1. Cultural management practices of the farmers in the different production sites
.
STAGE
ENGLANDAD LONGLONG
SINIPSIP
LOO
BALILI
CABUTO-
TAN
.
LAND
PREPARATION
Activities
Weeding,
Not
Weeds plowed Weeding,
Weeding,
Weeding,
digging
applicable
under
digging
digging
digging
Implements
Grab hoe, sharp Japanese hoe Grab hoe
Japanese hoe
Grab hoe
Grab hoe,
wooden stick
Japanese hoe
Beds
Raised
Plastic pots
Raised
Raised
Raised
Raised
Medium
Soil
2:1 garden
Soil Soil Soil Soil
soil and
compost
PLANTING
Direct
Transplant
Direct
Direct
Direct
Direct
MODE
FERTILIZATION
Type
Compost
Compost and Compost Compost BSU
Compost
Organic
Green
and Growth
fertilizer
manure
enhancer
(Galactic),
(plant extracts) chicken dung,
green manure
28
Table 1. continued…
.
STAGE
ENGLANDAD LONGLONG
SINIPSIP
LOO
BALILI
CABUTO-
TAN
Application
Basal and side
Basal Basal
and
Basal Basal Basal
and
dress
sidedress
sidedress
Composition
Chicken dung,
Shredded
Chicken dung, Corn stalks
Chicken dung, Rice bran, soil,
of compost
sunflower, pig
grasses,
sunflower,
and leaves,
grasses,
indigenous
manure, crop
effective
available
chicken dung,
microorganism effective
residues, garden microorga-
weeds
yeast, grasses,
microorga-
soil
nism (EM)
raw sugar
nism, chicken
dung
Composition
Not applicable
Available
Weeds Grasses
and
Not applicable Weeds
of green
weeds in
plant stubble
manure
farm
IRRIGATION
Overhead
Sprinkler Rain-fed Overhead Overhead Overhead
PEST
MANAGEMENT
Cultural
Rouging,
Multiple
Rouging Multiple Mixed
Irrigation
control
planting of
cropping
cropping
cropping,
repellant plants
planting of
repellant
plants
Chipping Quality of Potato Accessions Grown Organically in Different Production Sites in Benguet / Esther Josephine D.
Sagalla. 2007
29
Table 1. continued…
.
STAGE
ENGLANDAD LONGLONG
SINIPSIP
LOO
BALILI
CABUTO-
TAN
Chemical
Biofungicide
Bacillus
Biofungi-cide
Garlic and
Biofungicide
Biofungicide
control
(Bacillus
thuringiensis (Bacillus
marigold
(Bacillus
(Bacillus
subtilis)
subtilis)
extracts
subtilis)
subtilis) +
baking soda +
Joy® +
Oriental herb
nutrient
(OHN)
Physical
Hand picking
Not
Hand picking, Sack barriers
Yellow traps
Hand picking
control
applicable
sack barriers
BASES FOR SEED SELECTION
Disease/ Pest
Resistant Resistant
Resistant Resistant Resistant Resistant
reaction
Yield
High High High High High High
Adaptability
Local
----
Frost and cold
----
----
Local
conditions
conditions
Other
----
Peel color for
---- Large
tubers
Tubers for
Large tubers
Characters
customer
and field
chips
and early
preference
storability
maturing
Chipping Quality of Potato Accessions Grown Organically in Different Production Sites in Benguet / Esther Josephine D.
Sagalla. 2007
30
Planting. Seeds or stem cuttings are planted directly in plots that have
been previously watered.
Fertilizer application. Compost consisting of chicken dung, sunflower, pig
manure, crop residues, and soil is prepared by the farmer before land preparation.
The compost is applied basally one to two weeks before planting and side-dressed
during hilling up one month after planting.
Irrigation. Watering of plants is done one to two times a week using
watering cans.
Pest
management. Diseases such as late blight are controlled by the farmer
through removal of diseased plant parts or rouging and use of a bio-fungicide
(Bacillus subtilis). Insects are controlled by hand picking and planting of repellant
crops (calla lily).
Seed
selection. The farmer prefers potato varieties which are resistant to
pest, high yielding, and adapted to local conditions.
Longlong, La Trinidad
Description of the farm. The farm is situated on a terraced area that is
1,342 m asl. The area that is devoted to organic production for more or less six
years is 1,500 m2 wide.
The crops, mostly vegetables and spices, are planted on beds bordered by
bricks that have been cemented in place. This practice of cementing the sides of
31
the beds will better conserve soil nutrients. The beds are partially shaded by
plastic roofing.
Cropping
pattern. Multiple cropping of vegetables (e.g lettuce, broccoli),
herbs (e.g. rosemary), sugar beet, and potato is practiced to encourage diversity in
the farm.
Land
preparation. The farmer plows the soil 12 inches deep using
Japanese hoe.
No land preparation was done for the potatoes since black plastic pots
were used and placed in between the beds.
Planting. For other vegetables, the farmer sows seeds in small plastic trays
then finally transplants the seedlings to the beds.
The rooted stem cuttings of potato were directly planted on the plastic
pots.
Fertilization. The farmer prepares his compost. The compost consists of
shredded grasses, collected from the farm, that are composted within 14 days with
the aid of an effective microorganism (EM) solution. One part compost and two
parts garden soil are mixed and placed in plastic pots prior to planting of potatoes.
Green manure is also added by the farmer twice during plant growth until
the pots are filled.
Irrigation. Water is applied to the plants using sprinklers.
Pest
management. The farmer controls pests through multiple cropping,
crop rotation, and use of microorganisms (Bacillus thuringensis).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
32
Seed
selection. The farmer prefers potato varieties which are resistant to
pest and diseases, high yielding, and produce tubers with unique skin color to
attract consumers.
Sinipsip, Buguias
Description of the farm. The farm has been cultivated organically for five
years. It is located on a terraced area that is several hundred meters away from the
main highway. The elevation of the farm is 2,350 m asl.
Highland vegetables such as carrots and Chinese cabbage are commonly
planted in the farm. The farm is also surrounded by a fence made of straw sacks
to prevent very strong winds from damaging the crops.
Cropping pattern. Prior to potatoes, the farm was planted with carrots and
radish. After potatoes, cabbage or Chinese cabbage is planted. At times, the
vegetables are also planted at the same time with potato.
Land preparation. Digging, making of raised beds, and pulverizing using
grab hoe are the common practices of the farmer. Weeds are plowed under to
serve as green manure.
Planting. Seeds or seedlings are directly sown on raised beds.
Fertilization. Basal and side-dress application of compost is the customary
practice. The compost prepared by the farmer consists of chicken dung,
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
33
sunflower, and other weeds. Green manure is also incorporated in the soil during
land preparation.
Irrigation. The farm is rain-fed.
Pest management. Pests are controlled through hand picking, rouging, and
using of yellow traps and a bio-fungicide (Bacillus subtilis). Straw sacks that
serve as barriers to wind and indirectly to pests, surround the farm.
Seed selection. The farmer selects potato varieties based on resistance to
pest, high yield, and tolerance to frost and cold.
Loo, Buguias
Description of the farm. The farm is located on a plain area with an
elevation of 1,638 m asl. It transitioned into an organic farm four years ago. The
crops commonly planted in the farm are highland vegetables and fruits.
Cropping
pattern. Rotation of lettuce or carrots, potato, and broccoli and/
or lettuce is done in the farm.
Land
preparation. Similar to the other sites, weeding, digging, and making
of raised beds using Japanese hoe are done. The soil is also pulverized before
planting. If the soil is too compact, the farmer irrigates the field before digging.
Planting. Seeds are directly planted on raised beds.
Fertilization. Compost consisting of corn stalk and leaves, chicken dung,
yeast, grasses, and raw sugar is applied basally with no side-dress application.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
34
In addition, grasses and plant stubble are incorporated after harvest to
serve as green manure for the next crop.
Irrigation. Plants are watered regularly from a natural spring. The water is
brought to the field through a rubber hose.
Pest
management. Insect pests and diseases are minimized through
multiple cropping, crop rotation, and use of a botanical pesticide made of garlic
and marigold extract.
Seed
selection. The farmer prefers potato varieties that are resistant to pest
and high yielding with large tubers. In addition, the tubers must also be adapted to
delayed harvesting with no or minimal decrease in quality.
Balili, La Trinidad
Description of the farm. The farm is located on a slightly sloping area with
an elevation of 1,336 m asl. The area has been devoted to organic farming for
more than three years.
Practices other than the use of pesticides and synthetic fertilizers are
employed to preserve the quality of the soil at the same time minimize pest.
Cropping
pattern. Rotation of beans, potato, and beans is practiced. The
land is fallowed for at least three months before beginning another rotation of
crops. Corn is planted on the borders of the farm to serve as barriers while
marigold is planted in between beds to serve as repellant against insects.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
35
Land
preparation. The area is first cleared of weeds and then dug and the
soil is pulverized. The beds are raised for more efficient sowing.
Planting. Commonly, seeds are directly sown on plots.
Fertilization. Basal application of BSU compost is the common practice. A
growth enhancer made of plant extracts is also applied to the soil one month after
planting.
Irrigation. Water is applied twice a week using watering cans.
Pest
management. Pests and diseases are controlled through the integration
of mixed cropping, planting of repellant crops such as marigold, use of yellow
traps, and applying a bio-fungicide (Bacillus subtilis).
Seed
selection. Potato varieties with high yield and resistance to pest and
diseases are preferred. Another basis of selection by the farmer is suitability to
processing.
Cabutotan, Bakun
Description of the farm. The farm has been devoted to organic production
for two years. It is located on a sloping area with an elevation of 1,588 m asl.
The farm is planted with different kinds of vegetables, spices, and root
crops. The farm is also bordered by a black net which serves as a barrier.
Cropping
pattern. Potato, cabbage, and potato or carrots or radish are
planted in rotation on the farm. The area is divided into lots where the crops are
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
36
rotated after each cropping season. Root crops such as sweetpotato border the
farm.
Land
preparation. The farm is cleared of weeds before digging. It is
cultivated using grab hoe and Japanese hoe. Plots are made and oriented parallel
to the slope of the land to prevent soil erosion and surface run off.
Planting. Direct planting of seeds or stem cutting is commonly practiced.
Fertilization. A combination of an organic fertilizer (Galactic), chicken
dung, and several weeds are applied basally to the soil. Based on the product
information, the organic fertilizer (Galactic) consists of rice bran, soil, indigenous
effective microorganism, and chicken dung.
Irrigation. Water is applied through overhead method using rubber hose.
Pest
management. Pests are controlled through controlled irrigation,
handpicking, and spraying of a mixture of a bio-fungicide (Bacillus subtilis),
baking soda, Joy®, and an oriental herb nutrient (OHN). The mixture is prepared
by the farmer and sprayed on the plants to prevent or minimize disease incidence.
Seed
selection. The farmer prefers potato varieties that are resistant to
pest, high yielding, early maturing, and adaptable to local conditions. Potato
varieties that can produce large tubers are also selected.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
37
Temperature and Relative Humidity
in the Different Production Sites
Potatoes grow best in sites with a temperature range of 150C to 220C
(Sano, no date). Almost all sites are within the optimum temperature range except
Sinipsip (Table 2).
Table 2. Average temperature and relative humidity of the different production sites
(October to March)
ENGLAN- LONG-
SINIP-
LOO BALILI CABUTO-
DAD
LONG
SIP
TAN
Temperature (0C)
16.48
20.49
12.76
17.74
18.36
16.19
Relative
87.67 80.81
92.88
75.25
79.81 87.50
Humidity (%)
Thus, potatoes may be produced successfully in any of the sites except
Sinipsip. Otherwise potatoes may be planted during the months of the year where
temperature may increase at Sinipsip.
Potatoes also grow successfully in sites with an average relative humidity
of 86% (Sano, undated). Sinipsip has a relative humidity which is too high. The
weather at the site was continually wet and cloudy which might greatly affect
potato yield and quality (Beukema and Van der Zaag, 1979). The rest of the sites
have relative humidities within the range of the optimum relative humidity for
successful potato production.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
38
Sugar and dry matter content which are critical quality factors for
processing potatoes are often affected by environmental factors in the production
site. High temperatures directly affect tuber physiology and inhibit starch
deposition. Also, low relative humidity, high solar radiation, and high wind speed
can reduce photosynthesis thereby reducing dry matter content and increasing
sugar content. Prolonged periods with overcast skies can reduce light intensity to
levels below that required for maximum dry matter production (Stark et al.,
2003).
Soil Properties in the Different Production Sites
Englandad, Atok
The soil pH decreased from 6.34 to 6.23 after harvest (Table 3). The
decrease in soil pH may have been effected by several factors such as high
rainfall, cold and humid climate, accumulation of soil organic matter, production
and removal of heavy harvest, etc (Singer and Munns, 2002). Englandad had
relatively low temperature (16.480C) and high relative humidity (87.67%) which
might have contributed to the decrease in soil pH even with the application of
compost.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
39
Table 3. Soil properties of the different production sites
ENGLAN-
LONG-
SINIP-
LOO BALILI
CABUTO-
DAD
LONG
SIP
TAN
Before planting
PH
6.34
6.64
6.23
6.50
6.69
6.25
OM (%)
4.50
17.50
7.00
2.00
3.50
3.00
N (%)
0.22
0.88
0.35
0.10
0.18
0.15
P (ppm)
395
75
360
400
160
5.00
K (ppm)
676 2,960 136 1,570 274 102
After harvesting
pH
6.23
6.76
6.47
6.51
7.02
5.96
OM (%)
4.00
6.00
10.00
2.50
3.00
2.50
N (%)
0.20
0.30
0.50
0.12
0.15
0.12
P (ppm)
405
360
315
270
160
7.00
K (ppm)
752
3,000
572
660
948
124
Soil pH may indirectly affect the processing quality of a potato tuber. The
release of nutrients in the soil is affected by pH. Soils with very low pH, for
instance, may make essential nutrients unavailable to plants. As a result, plant
growth and quality of potato tubers are affected.
As with pH, organic matter and nitrogen in the soil also decreased after
harvest which might indicate plant absorption and utilization. In contrast,
phosphorus and potassium of the soil increased after harvest which might be
attributed to the continuous application of compost in the site (Anonymous,
2006).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
40
Longlong, La Trinidad
The pH, phosphorus, and potassium of the soil increased after harvest
which might be due to the continuous application of compost and green manure in
the site. Continuous application of compost has been shown to increase soil
phosphorus levels. In addition, compost made from grasses has been shown to
contain approximately twice the potassium content of chicken manure
(Anonymous, 2006).
Soil organic matter and nitrogen, however decreased which may be a
result of plant absorption and utilization.
Soil organic matter may enhance the processing quality of potato
accessions by producing healthy tubers.
Sinipsip, Buguias
An increase of soil pH, organic matter, nitrogen, and potassium was
observed after harvest. The increase in these soil properties might be due to the
compost applied during the growth and development of the plants. Experiments
have shown that application of compost increases organic matter and nitrogen
levels in the soil (Anonymous, 2006)
The nitrogen content of the soil might affect dry matter and reducing sugar
content of the potato tubers (Beukema and Van der Zaag, 1979). In fact, potatoes
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
41
harvested from Sinipsip had the lowest dry matter which may be attributed to
little or no absorption of nitrogen.
Soil phosphorus, on the other hand, decreased from 360 ppm to 315 ppm
after harvest. The decrease in phosphorus might be attributed to plant absorption
or the occurrence of high rainfall in the site. Experiments showed that loss of
phosphorus through leaching often occurs in areas with high rainfall (Black,
1968).
Loo, Buguias
Similarly, pH, organic matter, nitrogen, and potassium of the soil
increased after harvest. The compost, which was applied by the farmer, could
have increased these soil properties.
The decrease of phosphorus after harvest could be due to plant absorption.
Phosphorus contributes to early tuberization in potatoes (Beukema and Van der
Zaag, 1979). Thus, phosphorus may contribute to high yield and tuber quality of
potatoes.
Balili, La Trinidad
Soil pH and potassium increased after harvesting which might be due to
the compost applied to the soil. Compost made from grasses was found to have
higher potassium than manure (Anonymous, 2006). Potassium does not always
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
42
affect yield of potatoes but influence tuber quality especially dry matter content
(Beukema and Van der Zaag, 1979).
The decrease in organic matter and nitrogen, on the other hand, could be
attributed to the absorption and utilization of the plants. Phosphorus content of the
soil remained the same even after harvest which may be an indication that the
phosphorus absorbed may have been replaced by the growth enhancer applied to
the soil.
Cabutotan, Bakun
A decrease in soil pH from 6.25 to 5.96 was observed after harvest. The
decrease in soil pH might be attributed to the relatively low temperature (16.190C)
and high relative humidity (87.50%) in the site. Low evaporation of water in the
soil due to high relative humidity and low temperature favors acidity or decrease
in soil pH (Singer and Munns, 2002).
Similarly, a decrease of organic matter and nitrogen after harvest was
observed which might be due to plant absorption.
Phosphorus and potassium, on the other hand, increased after harvest
which might be due to the compost applied by the farmer.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
43
Total Yield
Effect of Production Sites
Highly significant differences were observed in the yield of potatoes
planted in the different production sites (Table 4).
Table 4. Total yield of the potato accessions grown organically in different
production sites
TREATMENT
TOTAL YIELD
(g/plant)
Production Site (S)
Englandad
31.36c
Longlong
61.57a
Sinipsip
25.84c
Loo
40.41bc
Balili
50.20ab
Cabutotan
53.45ab
Accession (A)
380251.17
58.61b
676070
38.75c
Ganza
37.47c
285411.22
17.93d
573275
34.75c
676089
58.13b
5.19.2.2
40.71c
575003
27.39cd
13.1.1
80.51a
S x A
ns
CV (%)
49.94
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
44
Potatoes from Longlong significantly produced the highest yield per plant
(61.57) but were comparable with those harvested from Balili (50.20) and
Cabutotan (53.45). Potatoes grown at Sinipsip produced the lowest yield per plant
(25.84).
Yields are often a reflection of soil, weather, and management of the
farmer (Dahnke, 1993). Farmers in countries like Indonesia obtained low yields
from potato cultivars suited for processing due to inappropriate cultural
management practices employed. The farmers employed their usual management
practice for Granola which was a common variety among them at that time
(Sinung-Basuki, et al., 2000). Researchers later found out that some potato
cultivars suitable for processing require certain cultural management practices for
higher yield. Thus, high yield of potato plants in Longlong may be attributed to
the cultural management of the farmer. The plants were sown in pots containing
soil and compost. The pots were also placed in open plastic houses where the
plants were protected from rain and wind. The tubers might have developed
undisturbed by factors that might affect potatoes planted in open fields. The
compost applied to the soil might have also provided better nutrition for high
yield as shown by the soil properties in Table 3.
Furthermore, temperature and relative humidity in Longlong is within the
ideal temperature and relative humidity for potato growth and development (Table
2).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
45
Low yield exhibited by potatoes grown at Sinipsip, on the other hand, may
be attributed to the unfavorable environmental conditions of the site. Sinipsip was
mostly wet (90.83% RH), cold (13.070C), and cloudy during the growth of the
potato plants. The soil was also wet most of the time thus decreasing soil oxygen
and causing tuber damage leading to low yield (Sano, undated). It was also
observed that the conditions at Sinipsip did not only affect yield but also quality
of the chips. Some of the chips had purple pigments and soap-like taste.
Effect of Potato Accessions
Accession 13.1.1 significantly produced the highest yield of 80.51 g/plant
while 285411.22 produced the lowest yield (17.33 g/ plant) but was comparable
with most of the accessions.
The yield differences among the accessions may be attributed to the
genetic make-up of the accessions and the environmental conditions of the
production site.
It is important that a variety suitable for chipping has high yield. A high
yield will encourage farmers to cultivate such a variety making it easily available
to processors. A high yielding variety might also satisfy the quantity needed by
the processors for chipping.
In addition, tubers with high yield tend to have high dry matter content
and better quality of finished chips (Tawfik et al., 2002). Accession 13.1.1 having
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
46
the highest yield is among the accessions with high dry matter content and chip
recovery.
Interaction Effect
No significant differences are observed in the interaction of production
sites and potato accessions.
Accession 13.1.1 consistently produced the highest yield in all production
sites except at Longlong where 676089 had the highest yield. Furthermore, most
of the accessions namely 380251.17, Ganza, 573275, and 676089 gained the
highest yield at Englandad while other high yielders were harvested from
Cabutotan and Balili.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
47
Experiment 2: Processing Quality of Potato
Accessions in Different Production Sites
Tuber Characteristics
Tuber Skin
Accessions 380251.17, Ganza, 573275, 676089, and 13.1.1 had yellow
tuber skins in all production sites (Table 5a).
Table 5a. Tuber skin color of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
676070
Pink and
Pink and
Pink and
Pink and
Pink and
Pink and
purplish
purplish
red around purplish
purplish
purplish
red around red around eyes
red around red around red around
eyes
eyes
eyes
eyes
eyes
Ganza
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
285411.22 Purplish-
Purplish-
Purplish-
Purplish-
Purplish-
Purplish-
red
red
red
red
red
red
573275
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
676089
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
5.19.2.2
Yellow
Brownish Yellow
Brownish Brownish Yellow
575003
Yellow
Brownish Brownish Brownish Yellow
Yellow
13.1.1
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
* Standard character
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
48
Accessions 676070 and 285411.22 also retained their tuber skin color of
pink and purplish red respectively in all sites. The skin color of pink to red potato
tubers is due to the presence of anthocyanin pigments dissolved in the cell sap of
the periderm cells and the outer layer cells of the cortical parenchyma (Van Es
and Hartmans, 1981).
Accession 5.19.2.2, on the other hand, originally had brownish tuber skin
that changed to yellow in Englandad, Sinipsip, and Cabutotan. Similarly,
accession 575003 with yellow tuber skin turned brownish in Longlong, Sinipsip,
and Loo.
Skin color is caused by the presence of certain pigments in the cell sap of
periderm cells (Van Es and Hartmans, 1981). The change in skin color of potato
tubers in some sites might be attributed to higher or lower concentrations of such
pigments making the tuber skin appear darker or lighter. The conditions in the
production sites might have affected pigment production in the periderm.
In addition, tuber skin color is an inherent characteristic of the accession
and is one factor that may affect chip quality. Potato accessions with pink to red
peel for instance, shows up as a dark ring on the slice after chipping. Thus, tuber
skin must be buff (dull yellow) to tan colored (Gould, 1988) to reduce losses.
In terms of skin color, most of the accessions may be chipped even
without peeling. Using accessions 676070 and 285411.22 in chipping is however
a disadvantage due to their pinkish and purplish red tuber skin color.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
49
Tuber Skin Type
Accessions 676070, Ganza, 676089, and 575003 retained their smooth
tuber skins across locations (Table 5b). Accessions 380251.17 and 285411.22, on
the other hand, originally had smooth tuber skins that turned rough in Longlong
and Loo.
Table 5b. Tuber skin type of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Smooth
Rough
Smooth
Smooth
Smooth
Smooth
676070
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
Ganza
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
285411.22 Smooth
Rough
Smooth
Rough
Smooth
Smooth
573275
Smooth
Netted
Smooth
Smooth
Smooth
Netted
676089
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
5.19.2.2
Smooth
Netted
Smooth
Smooth
Netted
Netted
575003
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
13.1.1
Smooth
Smooth
Smooth
Netted
Netted
Netted
* Standard character
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
50
Similarly, accession 573275 had smooth tuber skin that turned netted in
Longlong and Cabutotan. In contrast, accessions 5.19.2.2 and 13.1.1 had netted
tuber skins that turned smooth in some sites.
The varying skin types of potato tubers across locations might be
attributed to the positioning of cell layers in the periderm of the tubers. Smooth
skinned potatoes (e.g. 575003) have cell layers that remain in position while
netted to rough skinned tubers have cell layers that have become partly detached
giving rise to a rough surface (Van Es and Hartmans, 1981). The conditions in the
sites (e.g. soil type, cultural and environmental conditions, stem maturity, etc.)
might have influenced the positioning of such cell layers (Nolte and Olsen, 2006).
Smooth skin is preferred in tuber for chip processing. Peeling becomes
more efficient and peeling loss is reduced. Accessions with netted peel generally
increases peel loss and decrease chip recovery as a result (Gould, 1988).
Thus, accessions which showed consistently smooth tuber skin might be
more advantageous in decreasing peel loss during processing.
Tuber Flesh Color
The tubers of the different potato accessions had varying flesh colors
across locations (Table 5c). Accessions 380251.17, 573275, and 676089 had
cream tuber flesh but turned to pale yellow in some production sites. Ganza with
pale yellow tuber flesh in most sites turned to cream in Englandad.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
51
Table 5c. Tuber flesh color of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Cream
Cream
Pale
Pale
Cream
Pale
yellow
yellow
yellow
676070
Pale
Pale
Yellow
Yellow
Yellow
Pale
yellow
yellow
yellow
Ganza
Cream
Pale
Pale
Pale
Pale
Pale
yellow
yellow
yellow
yellow
yellow
285411.22 White
White
Pale
Cream
Cream
Cream
yellow
573275
Cream
Pale
Cream
Cream
Cream
Cream
yellow
676089
Cream
Cream
Pale
Pale
Cream
Cream
yellow
yellow
5.19.2.2
Yellow
Yellow
Yellow
Yellow
Pale
Yellow
yellow
575003
Yellow
Pale
Pale
Pale
Pale
Yellow
yellow
yellow
yellow
yellow
13.1.1
Pale
Yellow
Yellow
Yellow
Yellow
Yellow
yellow
* Standard character
Accessions 676070 and 13.1.1, on the other hand, had yellow tuber flesh
that turned to pale yellow in Englandad, Longlong, and Cabutotan. In contrast,
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
52
accessions 5.19.2.2 and 575003 had pale yellow tuber flesh that turned to yellow
in some production sites such as Englandad and Cabutotan.
Finally, accession 285411.22 originally had cream tuber flesh which
turned to white in Englandad and Longlong, and pale yellow in Sinipsip.
Tuber flesh colors (especially of yellow and white tubers) are due to the
presence or absence of carotenoids (Brown et.al., 1993 cited by Edwards et.al.,
2002). Such pigments have higher concentrations in yellower tubers and lower
concentrations in whiter fleshed tubers. Furthermore, it appears that temperature
may increase or decrease the production of these pigments making tuber flesh
color darker or lighter. Thus, the varying flesh colors of the different accessions
across sites might be attributed to the differing concentrations of their pigments
(e.g. carotenoids) as affected by temperature in the production site.
Processors, however, are more concerned with the color of chips after
frying rather than tuber flesh color itself. But, potato tubers with white to yellow
flesh colors are commonly used.
Tuber Shape
Tuber shape of the different accessions varied across locations (Table 5d).
Accessions 380251.17 and 676070 originally had round tubers that became
oblong and elliptic respectively in some sites.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
53
Table 5d. Tuber shape of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Oblong
Oblong
Oblong
Oblong
Round
Elliptic
676070
Round
Elliptic
Round
Round
Round
Oblong
Ganza
Round
Oblong
Oblong
Oblong
Ovate
Obovate
285411.22 Ovate
Round
Round
Oblong
Com-
Round
pressed
573275
Oblong
Obovate
Oblong
Elliptic
Ovate
Oblong
676089
Long
Elliptic
Elliptic
Ovate
Ovate
Elliptic
oblong
5.19.2.2
Ovate
Obovate
Elliptic
Ovate
Ovate
Obovate
575003
Oblong
Oblong
Oblong
Obovate
Oblong
Oblong
13.1.1
Round
Oblong
Oblong
Round
Oblong
Com-
pressed
* Standard character
Ganza, 573275, 676089, and 5.19.2.2 produced ovate tubers in Balili but
tuber shape changed to round, oblong, obovate, and elliptic in some production
sites. Accessions 575003 and 13.1.1 also had oblong tubers that changed from
round to compressed tubers in other production sites.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
54
Finally, accession 285411.22 produced compressed tubers in Balili but
tuber shape changed to round in Longlong, Sinipsip, and Cabutotan; ovate on
Englandad; and oblong in Loo.
Tuber shape is relatively a varietal characteristic. However, growing
conditions may cause variations from this genetically determined trait (Van Es
and Hartmans, 1981). Thus, the differing conditions (e.g. soil type, cultivation,
spacing, etc.) in each site might have also influenced the varying tuber shapes of
each accession.
Shape of tubers is of particular importance in determining the suitability of
potatoes for the chip market. Shape of tubers directly affects the number of slices
per tuber and peel loss (Gould, 1988). Chippers prefer round to oblong shaped
tubers since their shape facilitates the removal of the peel more efficiently and
with less solid loss (Gould, 1988). Moreover, round to oblong shaped tubers tend
to have higher chip recovery. Thus, accessions such as 676070, 13.1.1,
380251.17, and others which were round to oblong had high chip recoveries.
Tuber Eye Depth
Tuber eye depth varies across sites and within accessions (Table 5e). Most
of the potato accessions (e.g. 13.1.1, 5.19.2.2, 676089, etc) had shallow tuber eye
depths that changed from medium to very deep in some production sites.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
55
Accessions 285411.22, on the other hand, had medium tuber eye depths
that became shallow in Longlong but very deep in Englandad and Cabutotan.
Also, the eyes of accession 575003 originally protruded in Balili but sank to
shallow or medium in most locations except Longlong.
Table 5e. Tuber eye depth of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Very deep Shallow
Shallow
Shallow
Shallow
Shallow
676070
Medium
Shallow
Medium
Medium
Shallow
Medium
Ganza
Medium
Shallow
Shallow
Shallow
Shallow
Shallow
285411.22 Very deep Shallow
Medium
Medium
Medium
Very deep
573275
Medium
Shallow
Shallow
Shallow
Shallow
Medium
676089
Shallow
Shallow
Shallow
Shallow
Shallow
Shallow
5.19.2.2
Medium
Shallow
Shallow
Shallow
Shallow
Shallow
575003
Medium
Protruding Shallow
Shallow
Protruding Shallow
13.1.1
Shallow
Shallow
Medium
Shallow
Shallow
Shallow
* Standard character
The varying eye depths of potato tubers across sites might be attributed to
the formation of cell layers in the tuber periderm (Van Es and Hartmans, 1981). It
is probable that conditions in the site (e.g. soil type, temperature, relative
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
56
humidity, etc.) might have affected cell layer formation giving rise to shallow or
deep tuber eyes
In addition, eye depth is an inherited characteristic and is often considered
as part of the shape (Gould, 1988). To reduce peel loss, cultivars with shallow eye
depths are preferred for processing. If eyes are too deep, it is necessary to peel
longer and deeper to remove the eye. Further, the eyes should not be colored since
they turn black or brown on chipping and end up as a defect (Gould, 1988).
Thus, the use of accessions 676089 and 13.1.1 may result in reduced peel
loss during chipping since both had consistently shallow eye depth in most sites.
Further, their yellow eye color is consistent with the tuber skin color and thus may
not cause browning on chip.
Dry Matter Content
Effect of Production Sites
Highly significant differences were observed in the dry matter content of
tuber of the potato accessions planted in the different sites (Table 6). Potatoes
grown at Balili significantly had the highest dry matter content of tubers while
those grown at Sinipsip had the lowest. The rest of the accessions grown at
Englandad and Longlong, Loo and Cabutotan had comparable tuber dry matter
contents.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
57
Dry matter content in the tubers is correlated with the potato variety, but
apart from this, soil type, climate, fertilization, pest control, etc. are also of
importance (Hesen and VanderSchild, 1979). Potatoes harvested from Sinipsip,
for instance, had the lowest dry matter content which may be an effect of the high
relative humidity (92.88%) of the site. Excessive water from high rainfall or
relative humidity will often result in tubers with low dry matter (Kellock, 1995).
Table 6. Dry matter content of tubers of the potato accessions grown organically
in different production sites
TREATMENT
DRY MATTER CONTENT
(%)
Production Site (S)
Englandad
20.11b
Longlong
19.83b
Sinipsip
17.42d
Loo
18.70c
Balili
20.78a
Cabutotan
19.01c
Accession (A)
380251.17
18.61c
676070
18.00c
Ganza
18.44c
285411.22
18.42c
573275
20.14ab
676089
20.62a
5.19.2.2
20.47a
575003
19.08bc
13.1.1
20.03ab
S x A
**
CV (%)
9.82
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
58
Furthermore, continuous cloud cover will decrease dry matter by reducing
the photosynthetic rate of the plant. It was observed that Sinipsip was continually
wet and cloudy which might have greatly contributed to the low dry matter
content of the potato accessions.
The high dry matter content of potatoes grown in Balili, on the other hand,
might be due to the optimum environmental condition of the site. Potatoes
normally grow best in areas with a temperature of 15 to 220C (Sano, undated) and
Balili is within the optimum temperature range for growing potatoes.
Effect of Potato Accessions
Highly significant differences are likewise observed in the tuber dry
matter content of the nine accessions used. Accession 676089 and 5.19.2.2
significantly had the highest tuber dry matter content but were comparable to the
tubers of 573275 and 13.1.1. The tubers of the remaining accessions are not
significantly different from each other.
Dry matter content is a strongly inherited characteristic (Kellock, 1995).
Varieties with higher dry matter content (>18%) tend to have higher yields and
better quality of finished chips (Tawfik et.al., 2001). A high dry matter also
results in lower oil absorption of the chip during frying (Hesen and Van der
Schild, 1979). In terms of dry matter alone, all the accessions may be processed
into potato chips since they have tuber dry matter contents of above 18%.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
59
However, for better chip quality, a tuber dry matter content of 20.3 – 22.3% is
best (Mosley and Chase, 1993). Accessions 676089 and 5.19.2.2 may yield better
chips compared with the other accessions.
Interaction Effect
A highly significant interaction is observed between production site and
the different potato accessions on dry matter content. Furthermore, 68% (R-value)
of the differences in dry matter content are due to the interaction of the two
factors, which mean that both factors are important in the selection for chip
processing.
Accessions 5.19.2.2 and 13.1.1 had consistently dry matter content of 18%
and above across all locations (Fig. 1). Although these accessions were exposed to
different organic management practice and environmental conditions, these
accessions still retained high dry matter content for chipping. Dry matter though
affected by different factors is still largely attributed to the genetic make-up of the
accessions.
Furthermore, dry matter content of above 18% was exhibited by all the
accessions harvested from Balili. The other sites revealed accessions with lower
than 18% dry matter content. However, the most accessions (380251.17, Ganza,
573275, 5.19.2.2, 13.1.1) with the highest tuber dry matter content were harvested
from Englandad.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
60
Conditions in the production site also have a bearing on increasing or
decreasing dry matter content of potato accessions. Selection of sites for
production of potatoes intended for chipping is, thus, important.
25
20
15
10
5
0
CABUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 1. Dry matter content (%) of the potato accessions grown organically in
different production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
61
Specific Gravity
Effect of Production Sites
Highly significant differences can be observed in the specific gravity of
the potatoes harvested from the different sites (Table 7).
Table 7. Specific gravity of the potato accessions grown organically in different
production sites
TREATMENT
SPECIFIC GRAVITY
Production Site (S)
Englandad
1.084a
Longlong
1.073abc
Sinipsip
1.060c
Loo
1.067bc
Balili
1.077ab
Cabutotan
1.069bc
Accession (A)
380251.17
1.071ab
676070
1.063b
Ganza
1.068ab
285411.22
1.066ab
573275
1.075ab
676089
1.076ab
5.19.2.2
1.084a
575003
1.069ab
13.1.1
1.074ab
S x A
**
CV (%)
2.26
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
62
Potatoes harvested from Englandad had the highest specific gravity but
comparable with potatoes harvested from Longlong and Balili. Lowest specific
gravity is found in potatoes harvested from Sinipsip.
Specific gravity is a measure of the potato solids or water content. It
influences the processing efficiency, oil absorption of the finished chip, and the
chip recovery (Gould, 1988). Specific
gravity
may
be
influenced
by
environmental factors in the production site (Stark et.al., 2003).
Temperature is the primary factor affecting specific gravity. High
temperature in a site often inhibits starch deposition and decrease specific gravity.
Thus, relatively low temperatures are ideal for increasing specific gravity.
Englandad, Longlong, and Balili had relatively low temperatures ideal for starch
deposition and increased specific gravity.
Sinipsip produced potatoes with low specific gravity which might be
attributed to the high relative humidity and prolonged overcast skies of the site.
High relative humidity may reduce photosynthetic rate to levels below that
required for maximum starch deposition, thus, lowering specific gravity (Stark et
al., 2003).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
63
Effect of Potato Accessions
Accession 5.19.2.2 significantly had the highest specific gravity but
comparable with the rest of the accessions except 676070 which had the lowest
specific gravity.
Generally, high chip recovery is obtained from accessions with high
specific gravity. Such accessions also have been shown to absorb less cooking oil
during the chipping process (Gould, 1988). Thus, accessions 5.19.2.2 including
13.1.1 which had one of the highest specific gravity also had one of the highest
chip recovery and moderately oily chips. It also had one of the highest dry matter
content, thus confirming Gould’s (1988) statement that specific gravity and dry
matter are positively correlated.
Interaction Effect
The highly significant interaction between accessions and production sites
implies that both factors influence specific gravity of potato tubers.
Most accessions with high specific gravity were harvested from
Englandad while those with low specific gravity were taken from Sinipsip (Fig.
2). This shows that environmental conditions in Englandad may have enhanced or
increased the specific gravity of the potato accessions. Relatively low temperature
and relative humidity in the production site may enhance the performance of
potato accessions with increased specific gravity, thus, improve chipping quality.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
64
Accessions 5.19.2.2 and 13.1.1, on the other hand, had the highest specific
gravity. These accessions might yield higher chips and absorb less oil. Selection,
therefore, of a suitable accession and appropriate production site is important in
improving chipping quality.
1
.14
1
.12
1.1
1.08
1 .06
1
.04
1
.02
1
CABUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 2. Specific gravity of the potato accessions grown organically in different
production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
65
Sugar Content
Effect of Production Sites
Sugar content in potatoes is one of the determining factors with respect to
the suitability of a potato variety for the processing industry (Coumou, 1991).
Table 8. Sugar content of the potato accessions grown organically in different
production sites
TREATMENT
SUGAR CONTENT
(0Brix)
Production Site (S)
Englandad
4.16ab
Longlong
4.31a
Sinipsip
3.55c
Loo
4.38a
Balili
3.94abc
Cabutotan
3.72bc
Accession (A)
380251.17
3.72
676070
4.29
Ganza
4.07
285411.22
3.84
573275
4.01
676089
3.96
5.19.2.2
3.91
575003
4.41
13.1.1
3.88
S x A
**
CV (%)
16.98
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
66
The sugar content of tubers largely depends on the genetic make-up of the
variety but may also be affected by the soil type, manuring, weather conditions,
etc. (Hesen, 1985) in the production site. Low sugar content results in better
quality of the processed product.
Potatoes produced from Sinipsip had significantly the lowest sugar content
but were comparable with potatoes harvested from Balili and Cabutotan (Table 8).
The highest sugar content was obtained from potatoes harvested in Loo and
Longlong.
One of the important factors affecting sugar production in tubers is air and
soil temperature. The low sugar content in potatoes from Sinipsip might be
attributed to the low temperature of the place. Low sugar production in tubers
happens at a temperature range of 8-120C (Hesen, 1985). Sinipsip had a
temperature range of 9.50 - 14.120C which might have contributed to low sugar
production in the tubers.
As a general rule, however, any environmental factor that increases
specific gravity also decreases sugars and vice versa (Stark et al., 2003).
Effect of Potato Accessions
No significant differences were observed in the sugar content of the tuber
of the different potato accessions. Tuber of accession 380251.17 had the lowest
sugar content while accession 575003 had the highest.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
67
Sugar content varies considerably between varieties and is an inherited
characteristic as reported earlier. Thus, the different sugar contents of the tubers
of the accessions may be attributed to the genetic make-up.
Sugar content of tubers also plays an important role in the color of the
resulting chips. High sugar content results in discolored or brown chips, which are
unacceptable to consumers (Verma, 1991). Accessions with low sugar content of
0.5 to 2.0% usually results in light colored chips and accessions with sugar
contents higher than 2% are unacceptable for frying (Feltran et al., 2004).
However, there were cases when accessions with as high as 6.690 Brix were used
for frying with no problems on chip quality (Feltran et.al., 2004). Thus, all the
accessions may produce light colored chips with no browning.
Interaction Effect
A highly significant interaction is observed in the sugar content of the
different accessions harvested from the different production sites. Most of the
tubers from accessions with low sugar content were harvested from Sinipsip (Fig.
3). This result may be attributed to the weather condition of the site. Low light
intensity due to cloudy skies and high relative humidity might have decreased
photosynthetic rate and thus sugar production in the tubers. Lowest sugar content
of tubers was exhibited by accession 13.1.1 harvested from Cabutotan. This result
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
68
was confirmed by the light yellow chips with no browning produced from the
accession.
6
5
4
3
2
1
0
CA
BUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 3. Sugar content of the potato accessions grown organically in different
production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
69
Chip Recovery
Effect of Production Sites
Highly significant differences were observed in the chip recovery of the
potatoes harvested from the different sites (Table 9).
Table 9. Chip recovery of the potato accessions grown organically in different
production sites
TREATMENT
CHIP RECOVERY
(%)
Production Site (S)
Englandad
80.58ab
Longlong
77.63ab
Sinipsip
69.85c
Loo
76.62b
Balili
82.74a
Cabutotan
80.83ab
Accession (A)
380251.17
81.41a
676070
81.78a
Ganza
78.04ab
285411.22
69.94c
573275
80.11a
676089
80.03a
5.19.2.2
78.57ab
575003
74.88b
13.1.1
78.07ab
S x A
*
CV (%)
8.62
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
70
Potatoes from Balili produced the highest percentage of chips recovered
but comparable with potatoes from Cabutotan, Englandad, and Longlong.
Potatoes from Sinipsip, on the other hand, produced the least percentage
of chips recovered. Chip recovery is usually attributed to dry matter or specific
gravity (Verma, 1991). Dry matter, on the other hand, is affected by cultural and
environmental conditions of the production site.
High dry matter of tubers usually produces high chip recovery. Thus,
potatoes from Balili which had the highest dry matter also had the highest chip
recovery. Likewise, potatoes harvested from Sinipsip had the lowest chip
recovery which might be attributed to the low dry matter.
Effect of Potato Accessions
Chip recovery among the different accessions had highly significant
differences. Accession 676070 had the highest chip recovery but not significantly
different from the rest of the accessions except for accessions 285411.22 and
575003.
Chip recovery is directly related to the dry matter (Verma, 1991) and
shape of the tuber (Gould, 1988). A high dry matter often results to increased chip
recovery. Round shaped tubers with a smooth surface is also preferred for easier
chipping and higher chip production (Gould, 1988).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
71
Accessions with high chip recovery such as 573275, 676089, 13.1.1, etc
also had relatively high dry matter contents. It is therefore important to choose
accessions with high dry matter for higher chip yield. There are exceptions
however, in accessions that have high dry matter but are prone to damage. Such
accessions become unacceptable for chipping. Damage decreases chip yield.
Interaction Effect
A significant interaction is observed which means that production site and
potato accessions play an important role in increasing chip recovery. Suitable
chipping varieties grown in appropriate production sites must be selected for high
chip recovery.
High chip recovery was observed from potatoes harvested at Longlong
and Balili. Conditions in these sites might have enhanced chip recovery of the
accessions (Fig. 4).
Accession 380251.17 had the highest chip recovery which might be
attributed to its relatively high dry matter content.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
72
100
80
60
40
20
0
CABUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 4. Chip recovery of the potato accessions grown organically in different
production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
73
Chip Color
Effect of Production Sites
Color is one of the most important factors in the evaluation of tubers for
chipping (Gould, 1988). Potatoes harvested from Longlong, Balili, and Cabutotan
produced light yellow chips while the rest of the accessions produced yellow
brownish chips (Table 10).
Table 10. Chip color of potato accessions grown organically in different
production sites
TREATMENT
CHIP COLOR
Production Site (S)
Englandad
3.00b
Longlong
3.00b
Sinipsip
4.00a
Loo
4.00a
Balili
3.00b
Cabutotan
3.00b
Accession (A)
380251.17
3.00b
676070
4.00a
Ganza
4.00a
285411.22
3.00b
573275
4.00a
676089
3.00b
5.19.2.2
3.00b
575003
4.00a
13.1.1
3.00b
S x A
*
CV (%)
13.99
Chipping Quality of Potato Accessions Grown Organically in Different Production
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74
The ideal color of chips is usually light yellow to yellow. Chip color may
be influenced by the growing environment, fertilization, cultural practices, or any
factor that will affect sugar content (Gould, 1988). Thus, the light yellow color of
chips produced by the potatoes harvested from Longlong, Balili, and Cabutotan
may be attributed to the weather and farmer’s practices in the sites. It may also be
attributed to the relatively low sugar content of the potatoes harvested from the
sites.
Effect of Potato Accessions
Highly significant differences were observed in the sugar content of the
different accessions. Accessions 380251.17, 285411.22, 676089, 5.19.2.2 and
13.1.1 produced light yellow chips while the rest of the accessions produced
yellow brownish chips.
Chip color is determined to a large extent by the sugar content of the
potato accession. The higher the sugar content the darker is the chip color. A dark
chip color might result to browning and bitter taste, which is unacceptable to
consumers (Kaiyun et al., 2004).
Accessions which produced light colored chips had relatively low sugar
contents (3.72 to 3.960 Brix). The yellow brownish chips were produced from
accessions with high sugar content (4.07 to 4.40 Brix). Dark colored chips are
generally the result of too high sugar content (Gould, 1988).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
75
Interaction Effect
A
significant interaction between accession and production site on chip
color is observed. This result indicates that the appropriate accession must be
grown in the right production site to produce light colored chips.
All the accessions harvested from Cabutotan produced light yellow chips
while most accessions from Englandad produced yellow brownish chips (Fig. 5).
Furthermore, accession 13.1.1 consistently produced light yellow chips in all
locations except at Balili. In contrast, accession 676070 produced yellow
brownish chips to brown chips.
5
4
3
2
1
0
CABUT
OTAN
BALILI
LOO
SINIPSI
P
LONGL
ONG
ENGLA
NDAD
Figure 5. Chip color of p
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
76
Chip Browning
Effect of Production Sites
There was no browning from the chips produced by the accessions
harvested from Longlong and Cabutotan while slight browning was observed
from the accessions harvested from the remaining production sites (Table 11).
Table 11. Chip browning of the potato accessions grown organically in different
production sites
TREATMENT
BROWNING PATTERN
Production Site (S)
Englandad
Slight
Longlong
None
Sinipsip
Slight
Loo
Slight
Balili
Slight
Cabutotan
None
Accession (A)
380251.17
None
676070
Slight
Ganza
Slight
285411.22
Slight
573275
Slight
676089
Slight
5.19.2.2
None
575003
None
13.1.1
None
Browning is a consequence of high sugar content. The sugars will react
with the amino acids (Maillard reaction) present in the tuber and cause chips to
Chipping Quality of Potato Accessions Grown Organically in Different Production
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77
fry dark or brown (Gould, 1988). Sugar content, on the other hand, is a
consequence of the condition of the production site.
There were cases, however, of tubers with as high as 6.690 Brix sugar
content which were suitable to frying (Feltran et.al., 2004). Although potatoes
from Longlong had one of the highest sugar content, browning was not observed.
Effect of Potato Accessions
No browning was observed in the chips processed from accessions
380251.17, 5.19.2.2, 575003, and 13.1.1. The tubers from the rest of the
accessions showed chips with slight browning.
Browning is attributed to the amount of sugar in the tuber. A low sugar
content usually limits excessive browning in the final chip (Gould, 1988). This
claim is confirmed by the absence of browning in the chips processed from
accessions 380251.17 and 13.1.1 which had sugar contents of 3.72 and 3.880 Brix,
respectively.
No browning was observed in accessions 5.19.2.2 and 575003 despite
their relatively high sugar content. The absence of browning in these accessions
may be attributed to shorter frying time. It was observed that there were
accessions which easily fry while other accessions took longer time to fry before
fully cooked.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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78
Sensory Evaluation
Effect of Production Sites
Crispiness. Moderately crispy chips were obtained from potatoes harvested from
Englandad, Longlong, Sinipsip, and Loo while crispy chips were produced from Balili and
Cabutotan (Table 12).
Table 12. Sensory evaluation of the potato chips processed from different potato accessions and production sites
CRISPINESS
FLAVOR
TEXTURE
OILINESS
APPEARANCE
GENERAL
ACCEPTABILITY
Production site (S)
Englandad
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Longlong Moderately
Moderately Slightly
Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Sinipsip Moderately
Slightly
Slightly
Moderately Like
Like slightly
crispy
perceptible firm
oily
moderately
Loo Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Balili Crispy Perceptible
Moderately
Moderately Like much
Like much
firm
oily
Cabutotan Crispy
Moderately
Moderately Moderately Like
Like moderately
perceptible firm
oily
moderately
Accession (A)
380251.17
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
676070
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Ganza
Moderately
Moderately Slightly
Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Chipping Quality of Potato Accessions Grown Organically in Different Production
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79
Table 12. continued…
CRISPINESS
FLAVOR
TEXTURE
OILINESS
APPEARANCE
GENERAL
ACCEPTABILITY
285411.22
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
573275
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
676089
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
5.19.2.2
Crispy
Moderately Moderately Moderately Like
Like moderately
perceptible firm
oily
moderately
575003
Crispy
Moderately Moderately Moderately Like
Like moderately
perceptible firm
oily
moderately
13.1.1
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Crispiness increases with dry matter content, which is in turn easily
affected by conditions of the site. That the potatoes from Balili produced crispy
chips, might be attributed to a high dry matter as affected by the conditions of the
site.
Flavor. Moderately perceptible potato chips were produced from almost
all sites except Sinipsip and Balili. Chips from Sinipsip had slightly perceptible
flavor. The chips had violet pigments with soapy taste which might be attributed
to the cold and high relative humidity of the site.
Chips from Balili had perceptible flavor which might be due to the good
quality tubers harvested from the site.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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80
Texture. Potato chips processed from the different sites were moderately
firm except those harvested from Longlong and Sinipsip, which were slightly
firm. The slightly firm texture of the chips might be due to the low dry matter of
the potato accessions harvested.
Oiliness. All potato chips processed from the different sites were
moderately oily. Oiliness of chips is usually affected by dry matter content of
tubers which is in turn affected by environmental factors.
Appearance. Potato chips produced from potatoes harvested from all
locations were liked moderately except for chips from Balili which were liked
much.
General
acceptability. Potato chips from Englandad, Longlong, Loo, and
Cabutotan were liked moderately. Chips from Sinipsip were liked slightly while
chips from Balili were liked much.
Effect of Potato Accessions
Crispiness. Most of the accessions produced tubers which were
moderately crispy except the tubers of accessions 5.19.2.2 and 575003 which
were crispy. Crispiness is related to the specific gravity or dry matter of the potato
accession. Accessions with high specific gravity tend to produce crispy chips
while those with low specific gravity produce soggy chips (Mosley and Chase,
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
81
1993). Tubers of accessions 5.19.2.2 and 575003 had one of the highest specific
gravity among the other accessions.
Flavor. Tubers of all the accessions had moderately perceptible flavor.
Flavor of a chip may be influenced by the potato accession itself. Sugar content
and other organic compounds in the tuber often affect chip flavor (Gould, 1988).
Texture. Most of the accessions produced tubers with moderately firm
chips except Ganza tubers which produced slightly firm chips. Texture of chips is
influenced by dry matter content of the different tubers. Accessions with high dry
matter often produce firm chips. Ganza which had one of the lowest dry matters
also produced slightly firm chips.
Oiliness. All the accessions produced tubers with moderately oily chips.
Oiliness of chips is often related to specific gravity of the tuber. Accessions
having higher specific gravity have also been shown to absorb less cooking oil
during frying (Gould, 1988). However, the influence of specific gravity of the
different accessions was not clearly seen in terms of chip oiliness. This result may
be attributed to the method of frying done in the study.
Appearance and general acceptability. The chips produced from tubers of
all the accessions were liked moderately.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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82
SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS
Summary
The chip quality of nine potato accessions grown organically in different
production sites was evaluated. The organically grown potato accession with the
best chipping quality and the effect of different production sites to chipping
quality were identified.
The cultural management practices of the organic farmers, relative
humidity and temperature, and soil properties in each site were also identified. It
was observed that each of these factors had a contributory effect to the quality of
the processed chips. For instance, dry matter and sugar content of potato tubers,
which are critical quality factors for processing potatoes, are directly affected by
relative humidity and temperature of the site.
Potatoes from Longlong produced the highest yield. Highest dry matter
content and specific gravity were also observed from potatoes harvested from
Balili and Englandad, respectively. Lowest sugar content, on the other hand, was
exhibited by potatoes harvested from Sinipsip which might be due to the low
temperature of the site.
Potatoes harvested from Balili produced the highest chip recovery but
comparable with those harvested from Englandad, Longlong, and Cabutotan.
Light yellow chips with slight to no browning were produced from potatoes
Chipping Quality of Potato Accessions Grown Organically in Different Production
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83
harvested in Longlong, Balili, and Cabutotan. Chips which were processed from
potatoes harvested at Balili were liked much by panelists while those processed
from potatoes in Sinipsip were liked slightly.
Accession 13.1.1 had the highest yield while 285411.22 produced the
lowest yield per plant. Accession 676089, on the other hand, had the highest dry
matter content but comparable with those of accessions 573275, 5.19.2.2, and
13.1.1. Accession 5.19.2.2 had the highest specific gravity while the lowest sugar
content was measured from accession 380251.17.
Accession 676070 also had the highest chip recovery but was comparable
with most of the accessions. Light yellow chips with slight to no browning were
produced by most of the accessions. In addition, the chips were moderately crispy
to crispy, moderately oily, and were liked moderately by panelists.
Production site and potato accession interacted significantly to affect dry
matter content, specific gravity, and sugar content. A significant interaction is also
observed on the chip recovery and chip color of potato tubers . This interaction
means that both site and accession are important considerations in organic
growing of potatoes for chipping.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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84
Conclusion
Balili is a good site for organic potato production intended for processing
since it consistently produced potatoes with good chip quality. Potatoes harvested
from Balili had one of the highest yield, dry matter content, specific gravity, and
chip recovery. Furthermore, potatoes from Balili had one of the lowest sugar
content, thus, producing light yellow chips with no browning. The chips were also
liked much by the panelists. Thus, conditions in Balili might have positively
influenced or enhanced the characteristics of the potato accessions for chipping.
Longlong and Cabutotan might also be excellent sites for organic potato
production intended for processing since potatoes harvested from the sites showed
good chipping quality. The potatoes also had high yield and high chip recovery.
Moreover, the chips produced were light yellow but were liked moderately by
panelists.
Among the potato accessions, accession 13.1.1 consistently showed traits
indicating good chip quality. It significantly produced the highest yield in most
production sites which might indicate adaptability to organic production and to
the local conditions of the sites. Furthermore, accession 13.1.1 had one of the
highest dry matter content, specific gravity, and chip recovery. It also had one of
the lowest sugar content, thus, producing light yellow chips with no browning.
Accession 5.19.2.2 also exhibited good chip quality since it had high dry
matter content, specific gravity, and chip recovery. It also produced light yellow
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
85
and crispy chips. However, 5.19.2.2 produced one of the lowest yields per plant,
which might discourage organic farmers from growing it.
Accession 13.1.1 planted in Balili might therefore be the best treatment
combination in producing tubers with good chip quality.
Recommendation
Based on the results of the study, accessions 13.1.1 and 5.19.2.2 are
recommended for chip processing. Balili, Longlong, and Cabutotan may also be
recommended for organic production of potato accessions suitable for chip
processing.
Further evaluation of potato accessions for chipping using more efficient
equipments such as fryers and chippers is also recommended for more accurate
results.
Finally, development of standard organic practices for potato production is
also recommended. Doing this will make evaluation of the adaptability and
chipping quality of potato accessions more accurate.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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86
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htm.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
92
APPENDICES
Appendix Table 1. Temperature and relative humidity of the different production
sites
PRODUCTION SITE
TEMPERATURE
RELATIVE HUMIDITY
(0C)
(%)
Englandad
October
---
---
November
17.50
86.00
December
15.06
89.00
January
16.88 88.00
MEAN
16.48 87.67
Longlong
October
21.25
82.50
November
21.21
79.75
December
20.12
78.62
January
19.36 82.37
MEAN
20.49 80.81
Sinipsip
November
13.65
92.50
December
13.78
96.00
January
14.12
83.00
February
9.50 100.00
MEAN
12.76 92.88
Loo
November
17.75
86.00
December
17.06
77.00
January
19.88
51.00
February
16.25 87.00
MEAN
17.74 75.25
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
93
Appendix Table 1. continued…
PRODUCTION SITE
TEMPERATURE
RELATIVE HUMIDITY
(0C)
(%)
Balili
November
19.05
78.00
December
18.58
79.50
January
17.50
83.75
February
18.30 78.00
MEAN
18.36 79.81
Cabutotan
December
15.00
93.50
January
16.75
78.00
February
15.50
86.50
March
17.50 92.00
MEAN 16.19
87.50
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
94
Appendix Table 2. Total Yield
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 36.76 51.32 48.57 136.65 45.55
676070
17.74 34.38 28.26 80.38 26.79
Ganza
15.71 10.29 10.00 36.00 12.00
285411.22 10.71 12.50 10.71 33.93 11.31
573275
27.78 15.71 39.71 83.20 27.73
676089
41.67 48.68 86.20 176.56 58.85
5.19.2.2
10.29 11.29 16.67 38.25 12.75
575003
15.71 21.67 15.28 52.66 17.55
13.1.1
100.00
22.72
86.36
209.09
69.70
LONGLONG 380251.17
46.67 25.00 170.00 241.67 80.56
676070
65.71 23.75 42.50 131.96 43.99
Ganza
87.78
82.50
106.67
276.94
92.31
285411.22 28.75 10.00 42.86 81.61 27.20
573275
46.67 47.50 46.25 140.42 46.81
676089
136.00
162.50
46.00
344.50
114.83
5.19.2.2
41.43 66.25 45.00 152.68 50.89
575003
22.00 34.29 41.43 97.71 32.57
13.1.1
60.00
35.00
100.00
195.00
65.00
SINIPSIP
380251.17 52.86 28.26 43.18 124.30 41.43
676070
17.89 13.70 17.33 48.92 16.31
Ganza
17.08 9.54 11.25 37.88 12.63
285411.22 9.38 5.45 8.00 22.83 7.61
573275
39.17 10.00 14.17 63.33 21.11
676089
39.40 19.60 11.33 70.33 23.44
5.19.2.2
42.22 17.50 27.04 86.76 28.92
575003
13.25 13.33 16.36 42.95 14.32
13.1.1
67.39 70.45 62.62 200.47 66.82
LOO
380251.17 14.38 42.67 70.71 127.76 42.59
676070
40.62 40.00 20.67 101.29 33.76
Ganza
41.55 10.38 20.50 72.43 24.14
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
95
Appendix Table 2. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 10.83 7.00 28.50 46.33 15.44
573275
41.38 37.50 47.50 126.38 42.13
676089
52.19 64.74 36.07 152.99 50.99
5.19.2.2
29.00 45.00 45.62 119.62 39.88
575003
48.67 20.38 13.67 82.72 27.57
13.1.1
61.25
85.77
114.58
261.60
87.20
BALILI
380251.17 44.72 79.41 84.38 208.51 69.50
676070
63.00 56.76 82.63 202.40 67.46
Ganza
40.00 40.83 40.56 121.39 40.46
285411.22
6.33
10.29
10.45
27.08
9.03
573275
19.27 52.37 57.35 128.99 42.99
676089
21.57 58.75 76.11 156.43 52.14
5.19.2.2
0.00
75.00
53.59
128.59
42.86
575003
58.83 21.80 58.70 139.33 46.44
13.1.1
56.00
68.21
119.38
243.60
81.20
CABUTOTAN
380251.17 91.88 57.39 66.90 216.17 72.05
676070
37.10 45.83 49.63 132.56 44.19
Ganza
32.27 51.88 46.52 130.67 43.56
285411.22 60.00 12.50 38.57 111.07 37.02
573275
32.50 17.86 32.86 83.21 27.74
676089
29.83 40.67 75.00 145.49 48.50
5.19.2.2
108.40
45.17
53.33
206.91
68.97
575003
24.54 28.75 24.44 77.74 25.91
13.1.1
157.83
96.67
84.85
339.34
113.11
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
96
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 45.55 80.56 41.43 42.59 69.50 72.05 351.68 58.61
676070 26.79
43.99
16.31
33.76
67.47
44.19
232.51
38.75
Ganza 12.00
92.31
12.63
24.14
40.46
43.56
225.10
37.47
285411.22 11.31 27.20 7.61 15.44 9.03 37.02 107.61 17.93
573275 27.73
46.81
21.11
42.13
43.00
27.74
208.52
34.75
676089
58.85 114.83 23.44 51.00 52.14 48.50 348.76 58.13
5.19.2.2 12.75 50.89
28.92
39.88
42.86
68.97
244.27
40.71
575003 17.55
32.57
14.32
27.57
46.44
25.91
164.36
27.39
13.1.1 69.70
65.00
66.82
87.20
81.20
113.11
483.03
80.51
TOTAL
282.23
554.16
232.59 363.71
452.10
481.05
2365.84
MEAN 31.36
61.57
25.84
40.41
50.20
53.45 43.81
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
2440.84
488.17
9.69** 0.0001
REPLICATION
12 233.40
19.45
0.39ns 0.9657
WITHIN SITE
ACCESSION 8
889.61
111.20
2.21* 0.0334
SITE*ACCESSION 40 1947.44 48.69 0.97ns 0.5368
ERROR
96 45945.79
478.60
TOTAL 161
159144.77
R-square
=
0.71
Coefficient of Variance (CV) = 49.94%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
97
Appendix Table 3. Dry matter content
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 30.00 26.00 17.00 73.00 24.33
676070
15.00 15.50 15.50 46.00 15.33
Ganza
15.50 16.50 28.00 60.00 20.00
285411.22 21.50 18.50 14.00 54.00 18.00
573275
24.00 22.50 21.50 68.00 22.67
676089
20.00 19.00 18.00 57.00 19.00
5.19.2.2
18.50 21.00 30.00 69.50 23.17
575003
16.50 16.00 17.00 49.50 16.50
13.1.1
20.00 21.50 24.50 66.00 22.00
LONGLONG 380251.17 17.50 17.50 17.50 52.50 17.50
676070
20.50 22.00 21.00 63.50 21.17
Ganza
19.00 19.50 19.50 58.00 19.33
285411.22 22.00 18.50 19.50 60.00 20.00
573275
20.00 20.00 19.00 59.00 19.67
676089
23.50 23.50 23.50 70.50 23.50
5.19.2.2
21.00 20.00 17.50 58.50 19.50
575003
18.50 19.00 19.50 57.00 19.00
13.1.1
18.50 19.50 18.00 56.00 18.67
SINIPSIP
380251.17 16.50 16.50 17.00 50.00 16.67
676070
15.50 16.00 16.00 47.50 15.83
Ganza
17.00 17.00 17.00 51.00 17.00
285411.22 17.00 17.00 18.00 52.00 17.33
573275
17.00 16.50 15.50 49.00 16.33
676089
17.00 17.50 17.50 52.00 17.33
5.19.2.2
19.00 19.00 19.50 57.50 19.17
575003
17.50 18.00 18.00 53.50 17.83
13.1.1
19.00 20.00 19.00 58.00 19.33
LOO
380251.17 17.00 17.00 17.00 51.00 17.00
676070
17.00 18.00 17.50 52.50 17.50
Ganza
17.00 17.00 17.00 51.00 17.00
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
98
Appendix Table 3. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 16.50 16.50 17.00 50.00 16.67
573275
21.00 21.00 21.00 63.00 21.00
676089
19.00 19.50 19.00 57.50 19.17
5.19.2.2
20.00 20.00 19.50 59.50 19.83
575003
18.50 19.50 19.00 57.00 19.00
13.1.1
20.00 21.50 22.00 63.50 21.17
BALILI
380251.17 18.00 18.50 18.50 55.00 18.33
676070
21.50 21.50 22.00 65.00 21.67
Ganza
19.00 21.00 19.50 59.50 19.83
285411.22 19.50 20.00 20.00 59.50 19.83
573275
20.50 21.00 21.00 62.50 20.83
676089
21.00 26.50 22.50 70.00 23.33
5.19.2.2
21.50 20.50 20.50 62.50 20.83
575003
21.50 22.50 22.50 66.50 22.17
13.1.1
19.50 20.00 21.00 60.50 20.17
CABUTOTAN
380251.17 18.50 17.50 17.50 53.50 17.83
676070
17.00 16.00 16.50 49.50 16.50
Ganza
17.50 17.00 17.86 52.36 17.45
285411.22 18.50 18.50 19.00 56.00 18.67
573275
19.00 21.50 20.50 61.00 20.33
676089
21.00 21.00 22.00 64.00 21.33
5.19.2.2
19.50 21.00 20.50 61.00 20.33
575003
20.50 19.50 19.50 59.50 19.83
13.1.1
17.50 20.00 19.00 56.50 18.83
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
99
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 24.33 17.50 16.67 17.00 18.33 17.83 111.66 18.61
676070 15.33
21.17
15.83
17.50
21.67
16.50
108.00
18.00
Ganza 20.00
19.33
17.00
17.00
19.83
17.45
110.61
18.44
285411.22 18.00 20.00 17.33 16.67 19.83 18.67 110.50 18.42
573275 22.67
19.67
16.33
21.00
20.83
20.33
120.83
20.14
676089 19.00
23.50
17.33
19.17
23.33
21.33
123.66
20.62
5.19.2.2 23.17 19.50
19.17
19.83
20.83
20.33
122.83
20.47
575003 16.50
19.00
17.83
19.00
22.17
19.83
114.33
19.08
13.1.1 22.00
18.67
19.33
21.17
20.17
18.83
120.17
20.03
TOTAL
181.00
178.34
156.82 168.34
186.99
171.10
1042.59
MEAN 20.11
19.83
17.42
18.70
20.78
19.01 19.31
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
191.01
38.20
33.61** 0.0001
REPLICATION
12 13.64 1.14
0.32ns 0.9850
WITHIN SITE
ACCESSION 8
145.06
18.13
5.04** 0.0001
SITE*ACCESSION 40
378.64 9.47 2.63** 0.0001
ERROR
96 345.44 3.60
TOTAL 161
1073.78
R-square
=
0.68
Coefficient of Variance (CV) = 9.82%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
100
Appendix Table 4. Specific gravity
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 1.260 1.060 1.058 3.378 1.126
676070
1.048 1.050 1.050 3.148 1.049
Ganza
1.050 1.050 1.160 3.260 1.087
285411.22 1.082 1.066 1.043 3.191 1.064
573275
1.096 1.087 1.082 3.265 1.088
676089
1.074 1.067 1.064 3.205 1.068
5.19.2.2
1.066 1.079 1.260 3.405 1.135
575003
1.056 1.053 1.058 3.167 1.056
13.1.1
1.074 1.082 1.098 3.254 1.084
LONGLONG 380251.17 1.061 1.060 1.060 3.181 1.060
676070
1.076 1.085 1.079 3.240 1.080
Ganza
1.069 1.071 1.071 3.211 1.070
285411.22 1.085 1.066 1.071 3.222 1.074
573275
1.074 1.074 1.069 3.217 1.072
676089
1.093 1.093 1.093 3.279 1.093
5.19.2.2
1.079 1.074 1.060 3.213 1.071
575003
1.066 1.069 1.071 3.206 1.069
13.1.1
1.066 1.071 1.064 3.201 1.067
SINIPSIP
380251.17 1.055 1.055 1.058 3.168 1.056
676070
1.050 1.053 1.053 3.156 1.052
Ganza
1.058 1.058 1.058 3.174 1.058
285411.22 1.058 1.058 1.064 3.180 1.060
573275
1.058 1.055 1.050 3.163 1.054
676089
1.058 1.060 1.060 3.178 1.059
5.19.2.2
1.069 1.069 1.071 3.209 1.070
575003
1.060 1.064 1.064 3.188 1.063
13.1.1
1.069 1.074 1.069 3.212 1.071
LOO
380251.17 1.058 1.058 1.058 3.174 1.058
676070
1.058 1.064 1.060 3.182 1.061
Ganza
1.058 1.058 1.058 3.174 1.058
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
101
Appendix Table 4. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 1.055 1.055 1.058 3.168 1.056
573275
1.079 1.079 1.079 3.237 1.079
676089
1.069 1.071 1.069 3.209 1.070
5.19.2.2
1.074 1.074 1.071 3.219 1.073
575003
1.066 1.071 1.069 3.206 1.069
13.1.1
1.074 1.082 1.085 3.241 1.080
BALILI
380251.17 1.064 1.066 1.066 3.196 1.066
676070
1.082 1.082 1.085 3.249 1.083
Ganza
1.069 1.079 1.071 3.219 1.073
285411.22 1.071 1.074 1.074 3.219 1.073
573275
1.076 1.079 1.079 3.234 1.078
676089
1.079 1.080 1.087 3.246 1.082
5.19.2.2
1.082 1.076 1.076 3.234 1.078
575003
1.082 1.087 1.087 3.256 1.085
13.1.1
1.071 1.074 1.079 3.224 1.075
CABUTOTAN
380251.17 1.066 1.060 1.060 3.186 1.062
676070
1.058 1.053 1.055 3.166 1.055
Ganza
1.060 1.058 1.063 3.181 1.060
285411.22 1.066 1.066 1.069 3.201 1.067
573275
1.069 1.082 1.076 3.227 1.076
676089
1.079 1.079 1.085 3.243 1.081
5.19.2.2
1.071 1.079 1.076 3.226 1.075
575003
1.076 1.071 1.071 3.218 1.073
13.1.1
1.060 1.074 1.069 3.203 1.067
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
102
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17
1.13 1.06
1.06
1.06
1.07 1.06 6.44
1.071
676070 1.05 1.08
1.05
1.06
1.08 1.06 6.38
1.063
Ganza 1.09 1.07
1.06
1.06
1.07 1.06 6.41
1.068
285411.22
1.07 1.07
1.06
1.06
1.07 1.07 6.40
1.066
573275 1.09 1.07
1.05
1.08
1.08 1.08 6.45
1.075
676089 1.07 1.09
1.06
1.07
1.08 1.08 6.45
1.076
5.19.2.2 1.14 1.07
1.07
1.07
1.08 1.08 6.51
1.084
575003 1.06 1.07
1.06
1.07
1.09 1.07 6.42
1.069
13.1.1
1.08 1.07
1.07
1.08
1.07 1.07 6.44
1.074
TOTAL
9.78
9.65
9.54
9.61
9.69
9.63
57.90
MEAN 1.084
1.073
1.060
1.067
1.077
1.069 1.072
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
191.01
38.20
33.61** 0.0001
REPLICATION
12 13.64 1.14
0.32ns 0.9850
WITHIN SITE
ACCESSION 8
145.06
18.13
5.04** 0.0001
SITE*ACCESSION 40
378.64 9.47 2.63** 0.0001
ERROR
96 345.44 3.60
TOTAL 161
1073.78
R-square
=
0.43
Coefficient of Variance (CV) = 2.26%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
103
Appendix Table 5. Sugar content
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD
380251.17 3.20 4.20 3.00 10.40 3.50
676070
4.50 4.30 3.00 11.80 3.90
Ganza
5.00 5.40 4.50 14.90 5.00
285411.22 4.50 4.00 5.20 13.70 4.60
573275
4.10 4.10 4.60 12.80 4.30
676089
4.40 3.40 3.20 11.00 3.70
5.19.2.2
4.00 4.10 3.70 11.80 3.90
575003
3.50 4.80 4.20 12.50 4.20
13.1.1
4.30 4.40 4.60 13.30 4.40
LONGLONG
380251.17 2.80 3.40 3.20 9.40 3.10
676070
4.00 5.60 6.40 16.00 5.30
Ganza
4.10 3.40 4.00 11.50 3.80
285411.22 3.80 4.60 4.40 12.80 4.30
573275
3.90 4.80 4.80 13.50 4.50
676089
3.60 4.30 3.80 11.70 3.90
5.19.2.2
3.50 5.80 4.80 14.10 4.70
575003
5.90 4.40 4.30 14.60 4.90
13.1.1
3.90 4.30 4.50 12.70 4.20
SINIPSIP 380251.17 4.20 2.90 4.10 11.20 3.70
676070
4.90 4.10 4.30 13.30 4.40
Ganza
2.80 4.20 3.70 10.70 3.60
285411.22 3.20 3.20 2.60 9.00 3.00
573275
3.30 2.90 4.70 10.90 3.60
676089
2.80 3.20 2.20 8.20 2.70
5.19.2.2
3.30 4.20 3.20 10.70 3.60
575003
3.60 4.40 4.00 12.00 4.00
13.1.1
3.70 3.40 2.70 9.80 3.30
LOO
380251.17 4.00 3.90 4.10 12.00 4.00
676070
5.90 4.00 5.40 15.30 5.10
Ganza
4.60 3.70 4.40 12.70 4.20
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
104
Appendix Table 5. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 4.10 4.30 5.10 13.50 4.50
573275
4.10 3.20 3.90 11.20 3.70
676089
7.60 4.40 3.70 15.70 5.20
5.19.2.2
3.30 4.30 2.80 10.40 3.50
575003
4.30 3.90 6.00 14.20 4.70
13.1.1
5.10 4.10 4.10 13.30 4.40
BALILI
380251.17 4.70 4.00 4.00 12.70 4.20
676070
2.40 4.50 2.40 9.30 3.10
Ganza
3.90 3.60 4.40 11.90 4.00
285411.22 4.20 1.90 3.90 10.00 3.30
573275
3.90 3.80 4.30 12.00 4.00
676089
4.30 3.70 5.00 13.00 4.30
5.19.2.2
4.70 3.90 5.00 13.60 4.50
575003
4.20 3.90 3.90 12.00 4.00
13.1.1
3.60 4.40 4.00 12.00 4.00
CABUTOTAN
380251.17 4.10 3.20 3.90 11.20 3.70
676070
3.90 3.90 3.70 11.50 3.80
Ganza
4.40 3.20 3.90 11.50 3.80
285411.22 2.60 3.40 4.10 10.10 3.40
573275
4.10 3.90 3.80 11.80 3.90
676089
4.20 3.60 3.80 11.60 3.90
5.19.2.2
3.80 3.50 2.50 9.80 3.30
575003
4.70 4.70 4.70 14.10 4.70
13.1.1
2.30 2.70 3.80 8.80 2.90
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
105
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 3.50 3.10 3.70 4.00 4.20 3.70 22.20 3.72
676070 3.90 5.30
4.40
5.10
3.10
3.80
25.60
4.29
Ganza 5.00
3.80
3.60
4.20
4.00
3.80
24.40
4.07
285411.22 4.60 4.30 3.00 4.50 3.30 3.40 23.10 3.84
573275 4.30 4.50
3.60
3.70
4.00
3.90
24.00
4.01
676089 3.70 3.90
2.70
5.20
4.30
3.90
23.70
3.96
5.19.2.2 3.90 4.70
3.60
3.50
4.50 3.30
23.50
3.91
575003 4.20 4.90
4.00
4.70
4.00
4.70
26.50
4.41
13.1.1 4.40
4.20
3.30
4.40
4.00
2.90
23.20
3.88
TOTAL
37.50
38.70
31.90
39.30
35.40
33.40
216.20
MEAN 4.16 4.31
3.55
4.38
3.94
3.72 4.00
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
14.86
2.97
5.90** 0.0056
REPLICATION
12 6.04 0.50
1.09ns 0.3801
WITHIN SITE
ACCESSION 8
6.95
0.87
1.87ns 0.0728
SITE*ACCESSION 40
33.92 0.85 1.83** 0.0086
ERROR
96 44.47 0.46
TOTAL 161
106.24
R-square
=
0.58
Coefficient of Variance (CV) = 16.98%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
106
Appendix Table 6. Chip recovery
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 89.50 93.00 81.30 263.80 87.93
676070
76.90 84.30 83.50 244.70 81.57
Ganza
80.70 71.20 70.40 222.30 74.10
285411.22 76.50 84.10 79.00 239.60 79.87
573275
72.80 86.80 69.00 228.60 76.20
676089
--- --- --- --- ---
5.19.2.2
98.70 74.30 75.30 248.30 82.77
575003
81.70 96.30 72.80 250.80 83.60
13.1.1
79.00 80.30 76.50 235.80 78.60
LONGLONG 380251.17 80.80 75.20 79.70 235.70 78.57
676070
78.80 76.80 81.00 236.60 78.87
Ganza
89.30 83.70 78.30 251.30 83.77
285411.22 66.60 74.80 70.40 211.80 70.60
573275
88.20 81.80 87.10 257.10 85.70
676089
88.40 88.90 84.10 261.40 87.13
5.19.2.2
77.90 82.50 44.30 204.70 68.23
575003
77.20 73.80 57.60 208.60 69.53
13.1.1
77.90 74.90 75.90 228.70 76.23
SINIPSIP
380251.17 80.60 78.40 75.70 234.70 78.23
676070
85.70 74.10 89.10 248.90 82.97
Ganza
78.40 68.90 71.30 218.60 72.87
285411.22 66.50 30.30 65.30 162.10 54.03
573275
---
57.10
76.50
---
---
676089
62.20 73.50 50.60 186.30 62.10
5.19.2.2
81.20 69.30 68.70 219.20 73.07
575003
61.90 69.10 59.50 190.50 63.50
13.1.1
73.40 66.20 82.50 222.10 74.03
LOO
380251.17 75.10 73.30 72.20 220.60 73.53
676070
69.70 85.50 92.50 247.70 82.57
Ganza
72.70 76.60 71.80 221.10 73.70
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
107
Appendix Table 6. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 64.20 72.50 71.80 208.50 69.50
573275
66.90 79.70 87.30 233.90 77.97
676089
80.10 79.60 80.30 240.00 80.00
5.19.2.2
81.60 81.10 72.60 235.30 78.43
575003
72.40 80.60 66.10 219.10 73.03
13.1.1
81.10 79.80 81.60 242.50 80.83
BALILI
380251.17 82.90 85.60 82.00 250.50 83.50
676070
81.70 81.60 84.20 247.50 82.50
Ganza
82.90 81.70 80.10 244.70 81.57
285411.22 71.80 78.80 70.50 221.10 73.70
573275
83.10 83.90 85.00 252.00 84.00
676089
89.40 90.00 86.60 266.00 88.67
5.19.2.2
83.30 83.60 86.90 253.80 84.60
575003
82.30 87.20 82.20 251.70 83.90
13.1.1
88.00 72.30 86.40 246.70 82.23
CABUTOTAN
380251.17 86.50 90.00 83.60 260.10 86.70
676070
85.50 84.40 76.80 246.70 82.23
Ganza
79.10 84.40 83.30 246.80 82.27
285411.22 77.70 71.80 66.30 215.80 71.93
573275
84.20 85.90 86.50 256.60 85.53
676089
84.70 79.40 82.70 246.80 82.27
5.19.2.2
82.40 81.80 88.70 252.90 84.30
575003
73.30 77.50 76.40 227.20 75.73
13.1.1
77.40 77.20 74.80 229.40 76.47
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
108
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 87.93 78.57 78.23 73.53 83.50 86.70 488.46 81.41
676070 81.57
78.87
82.97
82.57
82.50
82.23
490.71
81.78
Ganza 74.10
83.77
72.87
73.70
81.57
82.27
468.28
78.04
285411.22 79.87 70.60 54.03 69.50 73.70 71.93 419.63 69.94
573275 76.20
85.70
66.80
77.97
84.00
85.53
476.20
80.11
676089 ---
87.13
62.10
80.00
88.67
82.27
400.17
80.03
5.19.2.2 82.77 68.23
73.07
78.43
84.60
84.30
471.40
78.57
575003 83.60
69.53
63.50
73.03
83.90
75.73
449.29
74.88
13.1.1 78.60
76.23
74.03
80.83
82.23
76.47
468.39
78.07
TOTAL
644.64
698.63
627.60 689.56
744.67
727.43
4132.53
MEAN 80.58
77.63
69.85
76.62
82.74
80.83 76.53
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
2765.71
553.14
6.61** 0.0036
REPLICATION
12
1004.39
83.70
1.85* 0.0510
WITHIN SITE
ACCESSION 8
1954.61
244.33
5.40** 0.0001
SITE*ACCESSION
39
2986.24
76.57
1.69* 0.0205
ERROR
93 4204.93
45.21
TOTAL 157
12915.89
R-square
=
0.67
Coefficient of Variance (CV) = 8.62%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
109
Appendix Table 7. Chip color
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD
380251.17 4.00 4.00 3.00 11.00 3.67
676070
4.00 4.00 4.00 12.00 4.00
Ganza
4.00 4.00 3.00 11.00 3.67
285411.22 4.00 4.00 3.00 11.00 3.67
573275
4.00 4.00 5.00 13.00 4.33
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
3.00 4.00 4.00 11.00 3.67
575003
4.00 4.00 3.00 11.00 3.67
13.1.1
4.00 3.00 3.00 10.00 3.33
LONGLONG
380251.17 3.00 3.00 3.00 9.00 3.00
676070
4.00 4.00 4.00 12.00 4.00
Ganza
4.00 3.00 3.00 10.00 3.33
285411.22 3.00 3.00 3.00 9.00 3.00
573275
3.00 3.00 3.00 9.00 3.00
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
4.00 3.00 3.00 10.00 3.33
575003
4.00 4.00 4.00 12.00 4.00
13.1.1
3.00 3.00 3.00 9.00 3.00
SINIPSIP 380251.17 3.00 3.00 3.00 9.00 3.00
676070
6.00 4.00 4.00 14.00 4.67
Ganza
4.00 3.00 3.00 10.00 3.33
285411.22 3.00 4.00 4.00 11.00 3.67
573275
5.00 4.00 4.00 13.00 4.33
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
3.00 3.00 3.00 9.00 3.00
575003
4.00 4.00 3.00 11.00 3.67
13.1.1
3.00 3.00 4.00 10.00 3.33
LOO
380251.17 4.00 4.00 4.00 12.00 4.00
676070
4.00 4.00 3.00 11.00 3.67
Ganza
4.00 4.00 4.00 12.00 4.00
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
110
Appendix Table 7. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 4.00 4.00 3.00 11.00 3.67
573275
3.00 3.00 4.00 10.00 3.33
676089
4.00 4.00 3.00 11.00 3.67
5.19.2.2
3.00 3.00 3.00 9.00 3.00
575003
3.00 3.00 3.00 9.00 3.00
13.1.1
3.00 3.00 4.00 10.00 3.33
BALILI
380251.17 3.00 3.00 3.00 9.00 3.00
676070
3.00 4.00 3.00 10.00 3.33
Ganza
4.00 3.00 3.00 10.00 3.33
285411.22 3.00 4.00 3.00 10.00 3.33
573275
4.00 3.00 4.00 11.00 3.67
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
4.00 4.00 3.00 11.00 3.67
575003
4.00 3.00 4.00 11.00 3.67
13.1.1
4.00 3.00 4.00 11.00 3.67
CABUTOTAN
380251.17 3.00 3.00 4.00 10.00 3.33
676070
3.00 3.00 4.00 10.00 3.33
Ganza
3.00 4.00 3.00 10.00 3.33
285411.22 3.00 4.00 3.00 10.00 3.33
573275
3.00 3.00 3.00 9.00 3.00
676089
3.00 3.00 4.00 10.00 3.33
5.19.2.2
3.00 3.00 3.00 9.00 3.00
575003
4.00 3.00 3.00 10.00 3.33
13.1.1
3.00 4.00 3.00 10.00 3.33
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
111
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 4.00 3.00 3.00 4.00 3.00 3.00 20.00 3.00
676070 4.00 4.00
5.00
4.00
3.00
3.00
23.00
4.00
Ganza 4.00
3.00
3.00
4.00
3.00
3.00
21.00
4.00
285411.22 4.00 3.00 4.00 4.00 3.00 3.00 20.00 3.00
573275 4.00 3.00
4.00
3.00
4.00
3.00
21.00
4.00
676089 3.00 3.00
3.00
4.00
3.00
3.00
19.00
3.00
5.19.2.2 4.00 3.00
3.00
3.00
4.00 3.00
20.00
3.00
575003 4.00 4.00
4.00
3.00
4.00
3.00
22.00
4.00
13.1.1 3.00
3.00
3.00
3.00
4.00
3.00
19.00
3.00
TOTAL
34.00
29.00
32.00
32.00
31.00
27.00
185.00
MEAN 4.00 3.00
4.00
4.00
3.00
3.00 3.00
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE
5
3.36
0.67
3.52* 0.0345
REPLICATION
12 2.30 0.19
0.82ns 0.6283
WITHIN SITE
ACCESSION 8
5.83
0.73
3.13** 0.0035
SITE*ACCESSION
40
16.25
0.41
1.74* 0.0144
ERROR
96 22.37 0.23
TOTAL 161
50.10
R-square
=
0.55
Coefficient of Variance (CV) = 13.99%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
112
Appendix Table 8. Conversion table for potato dry matter and specific gravity
DMC SG DMC SG DMC SG
14.0 1.043 17.9 1.063 21.7 1.083
14.2 1.044 18.1 1.064 21.8 1.084
14.4 1.045 18.3 1.065 22.0 1.085
14.6 1.046 18.5 1.066 22.2 1.086
14.8 1.047 18.7 1.067 22.4 1.087
15.0 1.048 18.9 1.068 22.6 1.088
15.2 1.049 19.0 1.069 22.8 1.089
15.4 1.050 19.2 1.070 23.0 1.090
15.6 1.051 19.4 1.071 23.1 1.091
15.8 1.052 19.6 1.072 23.3 1.092
16.0 1.053 19.8 1.073 23.5 1.093
16.2 1.054 20.0 1.074 23.7 1.094
16.4 1.055 20.2 1.075 23.9 1.095
16.6 1.056 20.4 1.076 24.1 1.096
16.8 1.057 20.6 1.077 24.3 1.097
17.0 1.058 20.8 1.078 24.5 1.098
17.2 1.059 21.0 1.079 24.7 1.099
17.4 1.060 21.2 1.080 24.9 1.100
17.6 1.061 21.3 1.081
17.8 1.062 21.5 1.082
Source: Kellock, 1995
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
113
Appendix 9. Tuber skin color (www.cip.cgiar.research.org)
Yellowish
Brownish
Pink and purplish around eyes
Purplish red
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
114
Appendix 10. Tuber flesh color (www.cip.cgiar.research.org)
White
Cream
Pale yellow
Yellow
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
115
Appendix 11. General tuber shape (CIP, 1977)
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
116
BIOGRAPHICAL SKETCH
The author was born to Ambrose Sagalla and Lily Sagalla on October 14,
1980. She is the third of four daughters.
Following family tradition, she finished her elementary education at Easter
School, Guisad, Baguio City. She then went to Benguet State University to finish
high school under the Agricultural Science curriculum. She continued her studies
in the same university and finished Bachelor of Science in Agriculture major in
Agronomy.
In August 2001, three months after graduation, she was employed as a
research assistant in one of the foreign funded projects at Northern Philippines
Root Crops Research and Training Center (NPRCRTC). After six months of
working as a research assistant, she resigned to work at the Department of
Agriculture CHARM Project (DA-CHARMP) as an enumerator. She then went
back to NPRCRTC under a different project funded by a Korean. She worked on
the processing of purple yams for 8 months.
Finally, she was hired on January 2003 as an instructor under the
Department of Agronomy, College of Agriculture. She is currently teaching basic
and major subjects in Agronomy.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
SAGALLA, ESTHER JOSEPHINE D. APRIL 2007. Chipping Quality of Potato
Accessions Grown Organically in Different Production Sites in Benguet. Benguet State
University, La Trinidad, Benguet.
Adviser: Belinda A. Tad-awan, Ph.D.
ABSTRACT
The chipping quality of nine potato accessions grown organically in different
production sites of Benguet was evaluated. The study aimed to determine the influence of
different production sites on the chipping quality of potato accessions grown organically,
identify the potato accession with the best chipping quality, and determine the interaction
between the production site and potato accession on chipping quality.
Potatoes grown in Balili, La Trinidad (1,336 m asl; 18.360C; 71.81% RH) had
relatively high yields and consistently produced tubers with good chip quality.
Furthermore, the harvested potatoes had high dry matter content (20.78%), specific
gravity (1.077), and chip recovery (82.74%). The potatoes also had one of the lowest
sugar content (3.940Brix), thus, producing light yellow chips with no browning. The
chips were also liked much by the panelists.
Potatoes harvested from Longlong (1,342 m asl; 20.490C; 80.81% RH) and
Cabutotan (1,588 m asl; 16.190C; 87.50% RH) also yielded well with a good chipping
quality and high chip recovery. Moreover, the chips produced were light yellow but were
liked moderately by panelists.
Accession 13.1.1 and 5.19.2.2 had the highest dry matter contents (20.03% and
20.47%), specific gravity measurements (1.074 and 1.084), and percent chip recovery
(78.07 and 77.57). Also, they had the lowest sugar contents (3.880Brix and 3.910Brix),
thus, producing the desired light yellow chips with no browning.
Production site and potato accession interacted significantly to affect dry matter
content, sugar content, chip recovery, chip color, and specific gravity. This interaction
means that both site and accession are important considerations in organic growing of
potatoes for chipping.
ii
TABLE OF CONTENTS
Page Number
Bibliography …….………………………………………………….
i
Abstract …………………………………………………………….
i
Table of Contents …………………………………………………..
iii
INTRODUCTION ………………………………………………….
1
REVIEW OF LITERATURE ………………………………………
5
MATERIALS AND METHODS …………………………………..
16
RESULTS AND DISCUSSION
Cultural Management Practices for Organic
Potato Production in Different Production
Sites ………………………………………………………...
26
Temperature and Relative Humidity in the
Different Production Sites ………………………………….
37
Soil Properties in the Different Production
Sites …………………………………………………………
38
Total Yield ………………………………………………….
43
Tuber Characteristics ……………………………………….
47
Dry Matter Content …………………………………………
56
Specific Gravity …………………………………………….
61
Sugar Content ……………………………………………….
65
Chip Recovery ………………………………………………
69
Chip Color …………………………………………………..
73
Chip Browning ………………………………………………
76
Sensory Evaluation ………………………………………….
78
iii
SUMMARY, CONCLUSIONS, AND
RECOMMENDATIONS
Summary
……………………………………………………. 82
Conclusions
…………………………………………………. 84
Recommendations
…………………………………………... 85
LITERATURE CITED ………………………………………………
86
APPENDICES ……………………………………………………….
91
BIOGRAPHICAL SKETCH ………………………………………...
115
iv
1
INTRODUCTION
Background of the Study
Potato varieties with high yield and acceptable processing quality are vital
requisites in our local processing industries. However, varieties with such
characteristics are limited. Only a few processing varieties such as Igorota,
Kennebec, Atlantic, and Columbus are grown in the highlands. Thus, there is an
increasing need to continuously evaluate more varieties or accessions that have
good processing qualities.
One of the processed products set for commercial production is the potato
chip. The chips first appeared during the mid 1850’s as a normal part of American
cooking. The potato was most likely sliced from the axis of the tuber and then
fried. It was only until a certain chef named George Crum sliced the tubers thin
enough to become crunchy potato chips. The chips, originally called ‘potato
crunches’ became popular in restaurants and grocery stores. They were eventually
introduced to England and neighboring countries during the early to mid part of
the 20th century (Harmon, 1998).
The potato chip industry continues to grow in countries worldwide
including the Philippines. In fact, 400 to 533 metric tons of fresh potato tubers
must be supplied merely for potato chip processing (Department of Agriculture et
al., undated). However, with the reported Philippine production of 68,000 metric
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
2
tons (FAO, 2002), only a portion of it is usually suitable for processing.
The Philippine government thus imports processed potatoes, which in 2001 were
valued at $16,858,000.00 (Gagnon, 2002).
Importance of the Study
Potato processors use whatever is available to them at the time of
processing. Some processors use a mixture of potato varieties which are both
imported and locally produced. As a result, the quality of potato chips is greatly
affected. For instance, potato varieties with high sugar content produce brown
chips with bitter taste. Other varieties with low dry matter content produce soggy
potato chips with high oil uptake and longer frying time.
Furthermore, two large-scale potato processors in Metro Manila mainly
procure the Granola variety because it is readily available but not ideal for
processing. It has low dry matter, high moisture content, and produces chips that
easily brown during frying (FRLD, 1995)
Potatoes are mainly grown conventionally with the application of
expensive chemicals and other synthetic compounds. When chipped, these
potatoes were found to contain as high as 73% pesticide residue (Lang, 2005).
Growing processing type potatoes organically is therefore a better alternative to
conventional production methods. It is in fact claimed that organically grown
potatoes taste better and contain more dry matter than conventionally-grown ones
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
3
(Finesilver, 1980). Health wise, organically grown potatoes are safe foods that are
free from toxic and harmful chemicals.
The location of production areas and the employed cultivation practices
also influence important quality factors of potato tubers for processing such as
specific gravity, dry matter, sugar content, and others. Thus, it is necessary to
grow potatoes in several locations to evaluate processing quality of different
accessions.
Several studies have been conducted to evaluate the suitability of potato
varieties to chipping. However, the varieties identified for processing are limited
and often susceptible to diseases.
It is therefore important not only to identify an appropriate potato
accession that can give good quality chips but also determine the effect of
location of production to potato chip quality.
Objectives of the Study
The objectives of this study were to:
1. determine the effect of different production sites on the chipping
quality of potato accessions grown organically;
2. identify the potato accession grown organically with the best chipping
quality across production sites; and
Chipping Quality of Potato Accessions Grown Organically in Different Production
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4
3. determine the interaction of the potato accessions and different
production sites on chipping quality.
Time and Place of the Study
The study was conducted at Englandad, Sinipsip, Loo, Balili, Longlong,
and Cabutotan where the potatoes were organically grown. The harvested
potatoes were processed at the College of Agriculture Complex, Benguet State
University, La Trinidad.
The study was conducted from October 2005 to March 2006.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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5
REVIEW OF LITERATURE
Origin and Distribution of Potato Chips
Piecing together how chips spread between 1853 and the early part of the
20th century is difficult. It is, however, assumed that the potato chips first
appeared in 1853 at Saratoga Springs, New York, which is considered its place of
origin. A certain cook named George Crum sliced the tubers very thinly to
produce crispy potato chips. The potato chips were then introduced to England in
1921 (Harmon, 1998) and eventually to other parts of the world.
The Potato Chip Industry
The potato chip industry has a demand for fresh potato up to 533 MT
daily. However, this demand for potatoes intended for processing is not met by
local production in volume and quality (HARRDEC, 1998).
Baguio and Benguet are the primary suppliers of potatoes for chips in the
Philippines. A newly emerging supplier is Mindanao. Metro Manila has been
absorbing about 50% of the potato chips. However, sales of potato chips in the
Philippines declined from 14% in 1990 to 6% in 1992 (Dep’t of Agriculture,
undated).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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6
Suitability of Potato Varieties for Chipping
Production
and
yield. Planting area and production of processing are very
limited. The main reasons are lack of suitable varieties for processing, little access
of potato farmers to these varieties, limited knowledge of industries on the
standards and requirements of processing potatoes, and susceptibility of
processing varieties to pest and diseases (Kaiyun et al., 2004).
High tuber yields and quality are also important determinants for the
suitability of a given variety for large-scale local production. Varieties with higher
specific gravity and dry matter tend to have higher yields and better quality of
finished chips. Moreover, color of chips depends on sugar content of tubers
(Tawfik et al., 2002).
Well-adapted potato cultivars that require fewer days to produce high
marketable yields would be specifically advantageous in much of the East. Unlike
most western production areas, short seasons (90-110 days) prevail in much of the
East, especially in northern areas. Early-maturing cultivars would also be useful
in intensively managed systems (e.g. organic, hoop houses, etc), especially if
access to the earliest markets and/or escape from persistent disease and insect
pressure (NERA, 2002).
Available varieties. Choosing varieties is very important for chip
processing, however, small-scale producers use varieties that are available to them
at the time of processing. As a result, the quality of chips varies tremendously, as
Chipping Quality of Potato Accessions Grown Organically in Different Production
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7
the processing quality is a function of both physical and chemical factors of the
tubers (Illeperuma and Wickramasinghe, 2000).
Moreover, potato varieties for processing suffer from poor varietal
improvement (Dep’t of Agriculture, undated).
Locally
grown
potato
varieties in the country have very low dry matter content (15% to 18%) which is
not suitable for processing. The development of suitable varieties (i.e. adapted to
the local growing conditions and acceptable to processors and consumers) is
therefore very necessary not only to help local farmers but also to develop the
country’s potato processing industry (HARRDEC, 1998).
Several potato varieties have been identified to be adaptable to the
country’s agro-climatic conditions such as the Chipeta and Atlantic for chips, and
the Kennebec and Century Russet for both chips and fries. These varieties are now
being tested in various experimental farms in the Cordillera and in the growing
areas of Mindanao (Department of Agriculture, undated).
Dry matter content and specific gravity. Potato varieties with high dry
matter content are considered suitable for chips as the dry matter content is
associated with mealiness, crispness, and reduced oil uptake in the fried chips
(Illeperuma and Wickramasinghe, 2000).
Potato varieties for chipping has to have high dry matter content (19% and
above). High dry matter content gives high chip yield with low fat content.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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8
Further, to obtain light colored chips, the reducing sugar content should be less
than 0.2% (NPRCRTC, undated).
For the production of potato chips, varieties with dry matter content of 22-
24% are required. The content of reducing sugars in the potato is also a
determining factor with respect to the suitability of a potato variety for
processing. Usually, the lower the reducing sugar content, the better the quality of
the product. Potato varieties with 0.2% reducing sugar are acceptable for chips
(Coumou, 1991).
The specific gravity or the dry matter content of potatoes are important
because it influences the uptake of fat or oil during frying. Higher yield of
processed products and lower oil uptake is a result of potatoes with high specific
gravity (Verma, 1991).
High specific gravity is particularly important in the production of potato
varieties for chips because of greater surface area to volume ratio in chips.
Moreover, chip crispiness and lack of oiliness increases with increasing specific
gravity (Scanlon, 2006).
Sugar
content. Processors prefer varieties that are best suited to produce
light colored chips. However, maintenance of the desired color is the major
problem associated with the chipping industry. The varieties used have inherent
differences with respect to their chip color. These varieties contain different levels
of reducing sugar, which are used to predict the suitability of potato tubers for
Chipping Quality of Potato Accessions Grown Organically in Different Production
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9
chip processing, as they are often responsible for color development (Illeperuma
and Wickramasinghe, 2000).
A reducing sugar content of 0.25 to 0.30 mg-g^sup-1^ fresh weight or
0.025% to 0.030% on fresh weight basis is the maximum concentration allowed in
tubers used for chips (Oltmans and Novy, 2002).
Potatoes destined for making chips, French fries and other fried products,
need to have low sugar content to avoid browning of the finished product. The
sugar content of potatoes is determined by the genotype and several pre and post-
harvest factors (Kumar et al., 2004).
Morphological
characters. Potato chipping varieties should have round
and uniform tuber shape, light brown tuber skin color, shallow eye depth, and free
from defects. Moreover, these varieties must have low reducing sugar (< 0.2%)
and moderate dry matter content (20-25%) (Kaiyun, 2004).
Large round tubers are preferred by the chipper, since their size and shape
facilitate the removal of the peel more efficiently and with less solid loss. Further,
cultivars with shallow eyes and few in number are to be preferred. If the eyes are
deep, it is necessary to peel for longer periods of time to remove the eye. Potato
varieties with high specific gravity are also preferred because they have been
shown to absorb less cooking oil during the chipping process (Gould, 1988).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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10
Potato Chip Quality
Good quality potato chips have a light color with little vascular
discoloration. The color of potato chips depends on the reducing sugar content of
the potatoes. Potato chips must also have a pleasing and desirable flavor, thus
potatoes used in chipping must not be bitter or have other off-flavors. The flavor
of potato chips is more complex than that of boiled, baked or mashed potatoes,
since the cooking temperatures are higher, and the absorbed oil contributes to the
overall flavor profile of the product (Scanlon, 2006).
An important factor influencing potato chip color is the level of reducing
sugars, glucose and fructose, at the time of frying. Glucose and fructose are the
products of sucrose hydrolysis mediated by the enzyme invertase. Increasing
concentrations of reducing sugars in the tuber correlate with darker chip color
(Oltmans and Novy, 2002).
Chipping quality is a genetically transmissible character. Potatoes that
produced light-colored chips after cold storage and reconditioning were shown to
transmit the ability to produce light-colored chips to their progenies (Oltmans and
Novy, 2002).
Many factors contribute to potato chip quality. This includes maturity of
tuber, shape, thickness, skin, peel, eyes, skin and flesh color, defects, specific
gravity, temperature, reducing sugar and sucrose content, and chipability. Chip
manufacturing procedures, such as peeling, slice thickness and uniformity, oil
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
11
type and temperature and packaging methods and materials all have a direct
impact on potato chip quality (Ohio State University, 2002).
The quality of chips is determined by appearance, color, taste/ flavor,
texture, moisture content, oil content and nutritional value. Color is by far the
most important quality characteristic followed by oil content (Hesen, 1991).
Influence of Production Site to Processing Quality of Potatoes
Experiments have shown a high effect of the factor “site” on the suitability
for processing of different potato varieties in organic farming. The results of these
experiments confirm the influence of site of production on the quality of potatoes
for processing (FAL, 2005).
The sugar content of potatoes is affected by the climatic factors in a
location, such as temperature during growth, minimal nutrition, and irrigation
(Kumar et al., 2004).
The amount of sucrose found in potatoes at harvest is influenced by
planting date, growing location, soil fertility, water availability, and any stress-
inducing event (Campbell and Bagley, 2006).
Specific gravity of tubers is influenced by the cultural management of
farmers in a location. Specific gravity generally decreases with reduced water
application and increased available nitrogen (Ojala et al, 1990).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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The variation in specific gravity, yield and percent yield of large size
tubers may be caused by cultivation practice, climatic condition, time of planting
and harvesting, location, etc. Hence, it is necessary to grow the selected clones at
several locations for further evaluation of processing quality, specific gravity,
yield, and percent yield of large size tubers (Tantidham et al., 1991).
Both the specific gravity and the dry matter content varied with the variety
and the location of production. Such variation has been reported for many
varieties grown in other countries (Verma, 1991).
Organic Farming in Potatoes
Varietal
selection. In selecting varieties for organic potato production,
varieties suited to organic production and those which best suit the intended
market should be selected and grown (Dep’t of Agriculture for Northern Ireland,
1996).
Crop
rotation. Potato plants are easy to grow, but they aren’t the easiest to
grow using organic methods. Potatoes are prone to quite a few insect pests and
diseases that can be a challenge to manage organically (Grubinger, 2005). Thus,
organic potatoes must be a part of an overall rotation. This will involve building
up of soil fertility and then exploiting that fertility with a nutrient-demanding crop
such as potatoes. Legumes must be included in the rotation to provide nitrogen.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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13
Without adequate nitrogen being available, the potato crop will yield very poorly
(Walsh, 2001).
Fertilizer
application. Potato growth depends on a supply of plant
nutrients, such as nitrogen, phosphorus, and potassium. Each of these nutrients
has specific functions for the growth and development of potato plants (Vander
Zaag, 1981). Based on the results of some studies, combined potassium (K) and
organic nitrogen (N) was found to be the most efficient fertilizer to increase yield
for crisp and french fry production (Haase, 2005).
Quality of Organically Grown Potatoes
Organically grown foods provide more nutrients than conventionally
grown foods. A recent study conducted by the Organic Center for Education and
Promotion found that organically grown foods contained on average 30% more
antioxidants than their conventional counterparts. A higher intake of antioxidants
has been shown to have a protective effect against development of cancer,
coronary heart disease, and cataracts (Lang, 2005).
In addition, glycoalkaloids (natural protective agents in potato plants and
tubers) and levels of potassium, magnesium, phosphorus, and sulfur were found to
be higher in organic potatoes (Martin, 2005). Vitamin C may be higher as well in
organically grown produce (Finesilver, 1989).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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Organically grown food also has higher dry matter content with a small
number of results showing them to be lower (Finesilver, 1989).
In terms of taste, potatoes grown organically obtained significantly higher
mean taste scores than conventionally grown after 6 months storage when tested
blindly by a panel (Finesilver, 1989). This difference may be explained by the
presence of glycoalkaloids which are higher in organic potatoes. Glycoalkaloids
are thought to move from outer (such as skin) to inner (such as flesh) layers of
potatoes during boiling and responsible for the perceived flavor differences
(Martin, 2005).
Comparison between Conventional and Organically Grown Potatoes
Fertilizer
application. Conventional fertilizing practices such as increased
application of synthetic N fertilizers may possibly result in higher crude protein
concentration in plant foods but poorer quality protein than organic practices
(Finesilver, 1989).
Pesticide
residue. Organically grown foods have fewer pesticide residues
than conventionally grown foods. Pesticide residues were found on 23% of
organic foods and 73% of conventional foods. When incidences of DDT and other
banned pesticides were removed, the incidence on organically grown foods fell to
13%, but only to 71% on the conventional crops. This result indicates that roughly
half of the incidence of residue found on organically grown foods is due to the
Chipping Quality of Potato Accessions Grown Organically in Different Production
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15
persistence of past pesticide use. The incidences of residue found on
conventionally grown produce were due to current applications (Lang, 2005).
Yield. Yields on organic farms are found to be lower than yields on
conventional farms, in large part because of damage by insects and diseases, but
profits are higher because organic potato prices are higher than conventional
prices. However, even with the price premium, good organic growing practices
are needed in order to assure decent marketable yields (Grubinger, 2005).
Organically grown products are on the average 57% more expensive than
conventionally grown ones. However, the higher cost is balanced by the benefits
of organically grown foods (Lang, 2005).
Statistical Tool Used to Analyze Sensory Evaluation of Processed Products
Data of sensory evaluation for chips and French fries were statistically
analyzed using a General Linear Model (GLM) procedure of SAS Institute. Least
Significant Difference (LSD) at P < 0.05 was used to separate treatment means
(Tawfik et al., 2002).
Computation of data for chip color was carried out using the multiple
linear regression analysis program (32 regression). The results of this computation
(coefficient of multiple correlation and regression equation) indicate that these
equations provide reasonably good prediction of the chip color of individual
potato cultivars (Mazza, 1983).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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MATERIALS AND METHODS
Nine potato accessions obtained from Northern Philippine Root Crop
Research and Training Center (NPRCRTC) were planted in different production
sites of Benguet and their tubers were processed as chips.
The treatments of the study replicated three times were:
Factor A: Production Sites (PS)
Place
Elevation
PS
1
Englandad,
Atok
2,
300
m
PS 2
Longlong, La Trinidad
1, 342 m
PS 3
Sinipsip, Buguias
2, 350 m
PS
4
Loo,
Buguias
1,
638
m
PS 5
Balili, La Trinidad
1, 336 m
PS
6
Cabutotan,
Madaymen 1,
588
m
Factor B: Potato Accessions (NOP)
Agency Code
NOP
1
380251.17
NOP
2
676070
NOP
3
Ganza
NOP
4
285411.22
NOP
5
573275
Chipping Quality of Potato Accessions Grown Organically in Different Production
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NOP
6
676089
NOP
7
5.19.2.2
NOP
8
575003
NOP
9
13.1.1
Experiment 1: Field evaluation of potato
accessions in different production sites
Nine potato accessions were planted in six organic farms of Benguet.
Rooted stem cuttings were used in all sites. The cuttings were planted in 1m x 5 m
beds at 30 cm between hills and rows in all sites except Longlong. The cuttings
were instead planted in plastic pots situated in partially shaded plastic houses.
Cultural management practices for organic production such as multiple
cropping, use of yellow traps, planting of repellant crops, and others were
followed in each site.
The potato accessions were then harvested and samples of mature and
sound potato tubers were obtained from the different sites.
The treatments in each site were laid out following randomized complete
block design (RCBD).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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The data gathered were:
1. Organic production practices of farmers. The farmers from each
location were interviewed using a prepared questionnaire to determine their
specific organic production practices that might affect chip quality.
2. Site description. The relative humidity, temperature, soil properties,
and elevation of the different production sites were taken.
3. Total yield/ accession (g/ plant). This was obtained by taking the total
weight of tubers from each treatment at harvest.
Experiment 2: Processing quality of potato accessions
grown in different production sites
Medium to large-sized potato tubers were weighed at 100 g per replication
per treatment. The tubers were then hand peeled, sliced into approximately 1 mm
thickness using a chipper and washed thoroughly with water (Plate 1). To reduce
oil absorption, the chips were drained on a cotton cloth. The potato chips were
deep-fried in vegetable oil and drained when bubbling of oil stopped and were
packed and sealed in polyethylene bags for sensory evaluation by ten non-
smoking panelists.
The treatments were laid out using the 9 x 6 factor factorial in randomized
complete block design (RCBD) with three replications.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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a. Chipping of potato tubers
b. Drying of potato chips
c.
Frying of potato chips
d. Packing of potato chips for sensory evaluation
Plate 1. Chipping of the different potato accessions
Chipping Quality of Potato Accessions Grown Organically in Different Production
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20
The data gathered were:
1. Tuber characteristics. The shape, peel color, peel texture, flesh color,
eye depth, and other characters were taken using the following scales (CIP, 1977):
a. Tuber skin color.
Rate
Description
0
White-cream
1
Yellow
2
Orange
3
Brownish
4
Pink
5
Red
6
Purplish-red
7
Purple
8
Dark purple-black
b. Tuber skin type
Rate
Description
0
Smooth
1
Rough (Flaky)
2
Partially netted
3
Totally netted
4
Very heavily netted
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c. Tuber flesh color.
Rate
Description
0
White
1
Cream
2
Pale yellow
3
Yellow
4
Deep Yellow
5
Red
6
Violet
7
Purple
d. General tuber shape
Rate
Description
0
Compressed
1
Round
2
Ovate
3
Obovate
4
Elliptic
5
Oblong
6
Long-oblong
7
Elongate
Chipping Quality of Potato Accessions Grown Organically in Different Production
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e. Depth of tuber eyes
Rate
Description
0
Protruding
1
Shallow
2
Medium
3
Deep
4
Very deep
2. Dry matter content (%). Twenty gram samples of potato tubers were
sliced into cubes, weighed, and ovendried (Memmert D-91126 Schwabach) at
800C for 24 hours. The dry matter content was then be computed using the
formula:
Dry matter content = 100% - % Moisture content
Where:
Fresh weight – Ovendry weight
% Moisture content =
x 100
Fresh
weight
3. Specific gravity. The dry matter content of the tubers was converted
into specific gravity measurement using a table of equivalents (Kellock, 1995).
4. Sugar content (0Brix). Juice was extracted from grated potato tubers.
The sugar content from the extracted juice was then taken using a digital
refractometer (Atago USA, Inc.).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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23
5. Chip recovery (%). The weight of unpeeled and chipped tubers was
taken and chip recovery was computed using the formula:
Weight of unpeeled tubers–Weight of chipped potatoes
Chip recovery =
x 100
Weight of unpeeled tubers
6. Chip color. Potato chip color was determined using the Potato Chip
Color Reference Standard prepared by the Potato Chip Institute International
(undated).
7. Chip browning. The browning of the chips was evaluated using the
following scale:
Scale
Description
1
No browning
2
Slight browning
3
Moderate browning
4
Severe browning
8. Sensory evaluation. The crispiness, flavor, texture, oiliness,
appearance, and general acceptability of the potato chips were evaluated by ten
panelists using the following rating scales:
a. Crispiness (Jose, 1998)
Scale
Description
Remarks
1
Very easy to crumble
Very crispy
2
Easy to crumble
Crispy
Chipping Quality of Potato Accessions Grown Organically in Different Production
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24
3
Crumbled without difficulty Moderately crispy
4
Crumbled with difficulty
Slightly crispy
5
Hard to crumble
Not crispy
b. Flavor (Jose, 1998)
Scale
Remarks
Description
1
Very strong flavor
Very perceptible
2
Strong flavor
Perceptible
3
Little flavor
Moderately perceptible
4
Very little flavor
Slightly perceptible
5
No flavor
Not perceptible
c. Texture (Jose, 1998)
Scale
Description
1
Firm
2
Moderately Firm
3
Slightly Firm
4
Not Firm
d. Oiliness
Scale
Description
1
Very oily
2
Oily
3
Moderately oily
Chipping Quality of Potato Accessions Grown Organically in Different Production
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25
4
Slightly oily
5
Not oily
e. Appearance
Scale
Description
1
Like very much
2
Like much
3
Like moderately
4
Like slightly
5
Not like/ Dislike
f. General acceptability
Scale
Description
5
Like very much
6
Like much
7
Like moderately
8
Like slightly
9
Not like/ Dislike
The data was analyzed through Analysis of Variance using the 9 x 6 factor
factorial in RCBD across sites. The significance among treatment means was
analyzed using Duncan’s Multiple Range Test (DMRT).
Chipping Quality of Potato Accessions Grown Organically in Different Production
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26
RESULTS AND DISCUSSION
Experiment 1: Field Evaluation of Potato
accessions in Different Production Sites
Cultural Management Practices for Organic Potato
Production in the Different Production Sites
Applying the appropriate cultural management practices in growing
potatoes for processing is important. Such practices could affect chip quality
(Table 1).
Englandad, Atok
Description of the farm. The farm is located at 2,300 m asl on a plateau. It
has been cultivated organically for four years and previously planted with
vegetables such as carrot, broccoli, cabbage, etc. Calla lily is also planted as
borders and windbreakers.
Cropping
pattern. Rotation of carrot (or cabbage, Chinese cabbage, etc.),
potato, and carrot is a common practice in the farm. Oftentimes, potato is also
planted at the same time with other crops such as brocolli. Garden pea, pechay, or
sweetpotato is planted on the borders of the farm.
Land
preparation. The common practices such as cleaning, digging, and
making of raised beds are done with the use of grab hoe and sharp wooden stick.
Before sowing, the soil is pulverized for more efficient root growth.
Chipping Quality of Potato Accessions Grown Organically in Different Production
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27
Table 1. Cultural management practices of the farmers in the different production sites
.
STAGE
ENGLANDAD LONGLONG
SINIPSIP
LOO
BALILI
CABUTO-
TAN
.
LAND
PREPARATION
Activities
Weeding,
Not
Weeds plowed Weeding,
Weeding,
Weeding,
digging
applicable
under
digging
digging
digging
Implements
Grab hoe, sharp Japanese hoe Grab hoe
Japanese hoe
Grab hoe
Grab hoe,
wooden stick
Japanese hoe
Beds
Raised
Plastic pots
Raised
Raised
Raised
Raised
Medium
Soil
2:1 garden
Soil Soil Soil Soil
soil and
compost
PLANTING
Direct
Transplant
Direct
Direct
Direct
Direct
MODE
FERTILIZATION
Type
Compost
Compost and Compost Compost BSU
Compost
Organic
Green
and Growth
fertilizer
manure
enhancer
(Galactic),
(plant extracts) chicken dung,
green manure
28
Table 1. continued…
.
STAGE
ENGLANDAD LONGLONG
SINIPSIP
LOO
BALILI
CABUTO-
TAN
Application
Basal and side
Basal Basal
and
Basal Basal Basal
and
dress
sidedress
sidedress
Composition
Chicken dung,
Shredded
Chicken dung, Corn stalks
Chicken dung, Rice bran, soil,
of compost
sunflower, pig
grasses,
sunflower,
and leaves,
grasses,
indigenous
manure, crop
effective
available
chicken dung,
microorganism effective
residues, garden microorga-
weeds
yeast, grasses,
microorga-
soil
nism (EM)
raw sugar
nism, chicken
dung
Composition
Not applicable
Available
Weeds Grasses
and
Not applicable Weeds
of green
weeds in
plant stubble
manure
farm
IRRIGATION
Overhead
Sprinkler Rain-fed Overhead Overhead Overhead
PEST
MANAGEMENT
Cultural
Rouging,
Multiple
Rouging Multiple Mixed
Irrigation
control
planting of
cropping
cropping
cropping,
repellant plants
planting of
repellant
plants
Chipping Quality of Potato Accessions Grown Organically in Different Production Sites in Benguet / Esther Josephine D.
Sagalla. 2007
29
Table 1. continued…
.
STAGE
ENGLANDAD LONGLONG
SINIPSIP
LOO
BALILI
CABUTO-
TAN
Chemical
Biofungicide
Bacillus
Biofungi-cide
Garlic and
Biofungicide
Biofungicide
control
(Bacillus
thuringiensis (Bacillus
marigold
(Bacillus
(Bacillus
subtilis)
subtilis)
extracts
subtilis)
subtilis) +
baking soda +
Joy® +
Oriental herb
nutrient
(OHN)
Physical
Hand picking
Not
Hand picking, Sack barriers
Yellow traps
Hand picking
control
applicable
sack barriers
BASES FOR SEED SELECTION
Disease/ Pest
Resistant Resistant
Resistant Resistant Resistant Resistant
reaction
Yield
High High High High High High
Adaptability
Local
----
Frost and cold
----
----
Local
conditions
conditions
Other
----
Peel color for
---- Large
tubers
Tubers for
Large tubers
Characters
customer
and field
chips
and early
preference
storability
maturing
Chipping Quality of Potato Accessions Grown Organically in Different Production Sites in Benguet / Esther Josephine D.
Sagalla. 2007
30
Planting. Seeds or stem cuttings are planted directly in plots that have
been previously watered.
Fertilizer application. Compost consisting of chicken dung, sunflower, pig
manure, crop residues, and soil is prepared by the farmer before land preparation.
The compost is applied basally one to two weeks before planting and side-dressed
during hilling up one month after planting.
Irrigation. Watering of plants is done one to two times a week using
watering cans.
Pest
management. Diseases such as late blight are controlled by the farmer
through removal of diseased plant parts or rouging and use of a bio-fungicide
(Bacillus subtilis). Insects are controlled by hand picking and planting of repellant
crops (calla lily).
Seed
selection. The farmer prefers potato varieties which are resistant to
pest, high yielding, and adapted to local conditions.
Longlong, La Trinidad
Description of the farm. The farm is situated on a terraced area that is
1,342 m asl. The area that is devoted to organic production for more or less six
years is 1,500 m2 wide.
The crops, mostly vegetables and spices, are planted on beds bordered by
bricks that have been cemented in place. This practice of cementing the sides of
31
the beds will better conserve soil nutrients. The beds are partially shaded by
plastic roofing.
Cropping
pattern. Multiple cropping of vegetables (e.g lettuce, broccoli),
herbs (e.g. rosemary), sugar beet, and potato is practiced to encourage diversity in
the farm.
Land
preparation. The farmer plows the soil 12 inches deep using
Japanese hoe.
No land preparation was done for the potatoes since black plastic pots
were used and placed in between the beds.
Planting. For other vegetables, the farmer sows seeds in small plastic trays
then finally transplants the seedlings to the beds.
The rooted stem cuttings of potato were directly planted on the plastic
pots.
Fertilization. The farmer prepares his compost. The compost consists of
shredded grasses, collected from the farm, that are composted within 14 days with
the aid of an effective microorganism (EM) solution. One part compost and two
parts garden soil are mixed and placed in plastic pots prior to planting of potatoes.
Green manure is also added by the farmer twice during plant growth until
the pots are filled.
Irrigation. Water is applied to the plants using sprinklers.
Pest
management. The farmer controls pests through multiple cropping,
crop rotation, and use of microorganisms (Bacillus thuringensis).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
32
Seed
selection. The farmer prefers potato varieties which are resistant to
pest and diseases, high yielding, and produce tubers with unique skin color to
attract consumers.
Sinipsip, Buguias
Description of the farm. The farm has been cultivated organically for five
years. It is located on a terraced area that is several hundred meters away from the
main highway. The elevation of the farm is 2,350 m asl.
Highland vegetables such as carrots and Chinese cabbage are commonly
planted in the farm. The farm is also surrounded by a fence made of straw sacks
to prevent very strong winds from damaging the crops.
Cropping pattern. Prior to potatoes, the farm was planted with carrots and
radish. After potatoes, cabbage or Chinese cabbage is planted. At times, the
vegetables are also planted at the same time with potato.
Land preparation. Digging, making of raised beds, and pulverizing using
grab hoe are the common practices of the farmer. Weeds are plowed under to
serve as green manure.
Planting. Seeds or seedlings are directly sown on raised beds.
Fertilization. Basal and side-dress application of compost is the customary
practice. The compost prepared by the farmer consists of chicken dung,
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
33
sunflower, and other weeds. Green manure is also incorporated in the soil during
land preparation.
Irrigation. The farm is rain-fed.
Pest management. Pests are controlled through hand picking, rouging, and
using of yellow traps and a bio-fungicide (Bacillus subtilis). Straw sacks that
serve as barriers to wind and indirectly to pests, surround the farm.
Seed selection. The farmer selects potato varieties based on resistance to
pest, high yield, and tolerance to frost and cold.
Loo, Buguias
Description of the farm. The farm is located on a plain area with an
elevation of 1,638 m asl. It transitioned into an organic farm four years ago. The
crops commonly planted in the farm are highland vegetables and fruits.
Cropping
pattern. Rotation of lettuce or carrots, potato, and broccoli and/
or lettuce is done in the farm.
Land
preparation. Similar to the other sites, weeding, digging, and making
of raised beds using Japanese hoe are done. The soil is also pulverized before
planting. If the soil is too compact, the farmer irrigates the field before digging.
Planting. Seeds are directly planted on raised beds.
Fertilization. Compost consisting of corn stalk and leaves, chicken dung,
yeast, grasses, and raw sugar is applied basally with no side-dress application.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
34
In addition, grasses and plant stubble are incorporated after harvest to
serve as green manure for the next crop.
Irrigation. Plants are watered regularly from a natural spring. The water is
brought to the field through a rubber hose.
Pest
management. Insect pests and diseases are minimized through
multiple cropping, crop rotation, and use of a botanical pesticide made of garlic
and marigold extract.
Seed
selection. The farmer prefers potato varieties that are resistant to pest
and high yielding with large tubers. In addition, the tubers must also be adapted to
delayed harvesting with no or minimal decrease in quality.
Balili, La Trinidad
Description of the farm. The farm is located on a slightly sloping area with
an elevation of 1,336 m asl. The area has been devoted to organic farming for
more than three years.
Practices other than the use of pesticides and synthetic fertilizers are
employed to preserve the quality of the soil at the same time minimize pest.
Cropping
pattern. Rotation of beans, potato, and beans is practiced. The
land is fallowed for at least three months before beginning another rotation of
crops. Corn is planted on the borders of the farm to serve as barriers while
marigold is planted in between beds to serve as repellant against insects.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
35
Land
preparation. The area is first cleared of weeds and then dug and the
soil is pulverized. The beds are raised for more efficient sowing.
Planting. Commonly, seeds are directly sown on plots.
Fertilization. Basal application of BSU compost is the common practice. A
growth enhancer made of plant extracts is also applied to the soil one month after
planting.
Irrigation. Water is applied twice a week using watering cans.
Pest
management. Pests and diseases are controlled through the integration
of mixed cropping, planting of repellant crops such as marigold, use of yellow
traps, and applying a bio-fungicide (Bacillus subtilis).
Seed
selection. Potato varieties with high yield and resistance to pest and
diseases are preferred. Another basis of selection by the farmer is suitability to
processing.
Cabutotan, Bakun
Description of the farm. The farm has been devoted to organic production
for two years. It is located on a sloping area with an elevation of 1,588 m asl.
The farm is planted with different kinds of vegetables, spices, and root
crops. The farm is also bordered by a black net which serves as a barrier.
Cropping
pattern. Potato, cabbage, and potato or carrots or radish are
planted in rotation on the farm. The area is divided into lots where the crops are
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
36
rotated after each cropping season. Root crops such as sweetpotato border the
farm.
Land
preparation. The farm is cleared of weeds before digging. It is
cultivated using grab hoe and Japanese hoe. Plots are made and oriented parallel
to the slope of the land to prevent soil erosion and surface run off.
Planting. Direct planting of seeds or stem cutting is commonly practiced.
Fertilization. A combination of an organic fertilizer (Galactic), chicken
dung, and several weeds are applied basally to the soil. Based on the product
information, the organic fertilizer (Galactic) consists of rice bran, soil, indigenous
effective microorganism, and chicken dung.
Irrigation. Water is applied through overhead method using rubber hose.
Pest
management. Pests are controlled through controlled irrigation,
handpicking, and spraying of a mixture of a bio-fungicide (Bacillus subtilis),
baking soda, Joy®, and an oriental herb nutrient (OHN). The mixture is prepared
by the farmer and sprayed on the plants to prevent or minimize disease incidence.
Seed
selection. The farmer prefers potato varieties that are resistant to
pest, high yielding, early maturing, and adaptable to local conditions. Potato
varieties that can produce large tubers are also selected.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
37
Temperature and Relative Humidity
in the Different Production Sites
Potatoes grow best in sites with a temperature range of 150C to 220C
(Sano, no date). Almost all sites are within the optimum temperature range except
Sinipsip (Table 2).
Table 2. Average temperature and relative humidity of the different production sites
(October to March)
ENGLAN- LONG-
SINIP-
LOO BALILI CABUTO-
DAD
LONG
SIP
TAN
Temperature (0C)
16.48
20.49
12.76
17.74
18.36
16.19
Relative
87.67 80.81
92.88
75.25
79.81 87.50
Humidity (%)
Thus, potatoes may be produced successfully in any of the sites except
Sinipsip. Otherwise potatoes may be planted during the months of the year where
temperature may increase at Sinipsip.
Potatoes also grow successfully in sites with an average relative humidity
of 86% (Sano, undated). Sinipsip has a relative humidity which is too high. The
weather at the site was continually wet and cloudy which might greatly affect
potato yield and quality (Beukema and Van der Zaag, 1979). The rest of the sites
have relative humidities within the range of the optimum relative humidity for
successful potato production.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
38
Sugar and dry matter content which are critical quality factors for
processing potatoes are often affected by environmental factors in the production
site. High temperatures directly affect tuber physiology and inhibit starch
deposition. Also, low relative humidity, high solar radiation, and high wind speed
can reduce photosynthesis thereby reducing dry matter content and increasing
sugar content. Prolonged periods with overcast skies can reduce light intensity to
levels below that required for maximum dry matter production (Stark et al.,
2003).
Soil Properties in the Different Production Sites
Englandad, Atok
The soil pH decreased from 6.34 to 6.23 after harvest (Table 3). The
decrease in soil pH may have been effected by several factors such as high
rainfall, cold and humid climate, accumulation of soil organic matter, production
and removal of heavy harvest, etc (Singer and Munns, 2002). Englandad had
relatively low temperature (16.480C) and high relative humidity (87.67%) which
might have contributed to the decrease in soil pH even with the application of
compost.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
39
Table 3. Soil properties of the different production sites
ENGLAN-
LONG-
SINIP-
LOO BALILI
CABUTO-
DAD
LONG
SIP
TAN
Before planting
PH
6.34
6.64
6.23
6.50
6.69
6.25
OM (%)
4.50
17.50
7.00
2.00
3.50
3.00
N (%)
0.22
0.88
0.35
0.10
0.18
0.15
P (ppm)
395
75
360
400
160
5.00
K (ppm)
676 2,960 136 1,570 274 102
After harvesting
pH
6.23
6.76
6.47
6.51
7.02
5.96
OM (%)
4.00
6.00
10.00
2.50
3.00
2.50
N (%)
0.20
0.30
0.50
0.12
0.15
0.12
P (ppm)
405
360
315
270
160
7.00
K (ppm)
752
3,000
572
660
948
124
Soil pH may indirectly affect the processing quality of a potato tuber. The
release of nutrients in the soil is affected by pH. Soils with very low pH, for
instance, may make essential nutrients unavailable to plants. As a result, plant
growth and quality of potato tubers are affected.
As with pH, organic matter and nitrogen in the soil also decreased after
harvest which might indicate plant absorption and utilization. In contrast,
phosphorus and potassium of the soil increased after harvest which might be
attributed to the continuous application of compost in the site (Anonymous,
2006).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
40
Longlong, La Trinidad
The pH, phosphorus, and potassium of the soil increased after harvest
which might be due to the continuous application of compost and green manure in
the site. Continuous application of compost has been shown to increase soil
phosphorus levels. In addition, compost made from grasses has been shown to
contain approximately twice the potassium content of chicken manure
(Anonymous, 2006).
Soil organic matter and nitrogen, however decreased which may be a
result of plant absorption and utilization.
Soil organic matter may enhance the processing quality of potato
accessions by producing healthy tubers.
Sinipsip, Buguias
An increase of soil pH, organic matter, nitrogen, and potassium was
observed after harvest. The increase in these soil properties might be due to the
compost applied during the growth and development of the plants. Experiments
have shown that application of compost increases organic matter and nitrogen
levels in the soil (Anonymous, 2006)
The nitrogen content of the soil might affect dry matter and reducing sugar
content of the potato tubers (Beukema and Van der Zaag, 1979). In fact, potatoes
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
41
harvested from Sinipsip had the lowest dry matter which may be attributed to
little or no absorption of nitrogen.
Soil phosphorus, on the other hand, decreased from 360 ppm to 315 ppm
after harvest. The decrease in phosphorus might be attributed to plant absorption
or the occurrence of high rainfall in the site. Experiments showed that loss of
phosphorus through leaching often occurs in areas with high rainfall (Black,
1968).
Loo, Buguias
Similarly, pH, organic matter, nitrogen, and potassium of the soil
increased after harvest. The compost, which was applied by the farmer, could
have increased these soil properties.
The decrease of phosphorus after harvest could be due to plant absorption.
Phosphorus contributes to early tuberization in potatoes (Beukema and Van der
Zaag, 1979). Thus, phosphorus may contribute to high yield and tuber quality of
potatoes.
Balili, La Trinidad
Soil pH and potassium increased after harvesting which might be due to
the compost applied to the soil. Compost made from grasses was found to have
higher potassium than manure (Anonymous, 2006). Potassium does not always
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
42
affect yield of potatoes but influence tuber quality especially dry matter content
(Beukema and Van der Zaag, 1979).
The decrease in organic matter and nitrogen, on the other hand, could be
attributed to the absorption and utilization of the plants. Phosphorus content of the
soil remained the same even after harvest which may be an indication that the
phosphorus absorbed may have been replaced by the growth enhancer applied to
the soil.
Cabutotan, Bakun
A decrease in soil pH from 6.25 to 5.96 was observed after harvest. The
decrease in soil pH might be attributed to the relatively low temperature (16.190C)
and high relative humidity (87.50%) in the site. Low evaporation of water in the
soil due to high relative humidity and low temperature favors acidity or decrease
in soil pH (Singer and Munns, 2002).
Similarly, a decrease of organic matter and nitrogen after harvest was
observed which might be due to plant absorption.
Phosphorus and potassium, on the other hand, increased after harvest
which might be due to the compost applied by the farmer.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
43
Total Yield
Effect of Production Sites
Highly significant differences were observed in the yield of potatoes
planted in the different production sites (Table 4).
Table 4. Total yield of the potato accessions grown organically in different
production sites
TREATMENT
TOTAL YIELD
(g/plant)
Production Site (S)
Englandad
31.36c
Longlong
61.57a
Sinipsip
25.84c
Loo
40.41bc
Balili
50.20ab
Cabutotan
53.45ab
Accession (A)
380251.17
58.61b
676070
38.75c
Ganza
37.47c
285411.22
17.93d
573275
34.75c
676089
58.13b
5.19.2.2
40.71c
575003
27.39cd
13.1.1
80.51a
S x A
ns
CV (%)
49.94
Chipping Quality of Potato Accessions Grown Organically in Different Production
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44
Potatoes from Longlong significantly produced the highest yield per plant
(61.57) but were comparable with those harvested from Balili (50.20) and
Cabutotan (53.45). Potatoes grown at Sinipsip produced the lowest yield per plant
(25.84).
Yields are often a reflection of soil, weather, and management of the
farmer (Dahnke, 1993). Farmers in countries like Indonesia obtained low yields
from potato cultivars suited for processing due to inappropriate cultural
management practices employed. The farmers employed their usual management
practice for Granola which was a common variety among them at that time
(Sinung-Basuki, et al., 2000). Researchers later found out that some potato
cultivars suitable for processing require certain cultural management practices for
higher yield. Thus, high yield of potato plants in Longlong may be attributed to
the cultural management of the farmer. The plants were sown in pots containing
soil and compost. The pots were also placed in open plastic houses where the
plants were protected from rain and wind. The tubers might have developed
undisturbed by factors that might affect potatoes planted in open fields. The
compost applied to the soil might have also provided better nutrition for high
yield as shown by the soil properties in Table 3.
Furthermore, temperature and relative humidity in Longlong is within the
ideal temperature and relative humidity for potato growth and development (Table
2).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
45
Low yield exhibited by potatoes grown at Sinipsip, on the other hand, may
be attributed to the unfavorable environmental conditions of the site. Sinipsip was
mostly wet (90.83% RH), cold (13.070C), and cloudy during the growth of the
potato plants. The soil was also wet most of the time thus decreasing soil oxygen
and causing tuber damage leading to low yield (Sano, undated). It was also
observed that the conditions at Sinipsip did not only affect yield but also quality
of the chips. Some of the chips had purple pigments and soap-like taste.
Effect of Potato Accessions
Accession 13.1.1 significantly produced the highest yield of 80.51 g/plant
while 285411.22 produced the lowest yield (17.33 g/ plant) but was comparable
with most of the accessions.
The yield differences among the accessions may be attributed to the
genetic make-up of the accessions and the environmental conditions of the
production site.
It is important that a variety suitable for chipping has high yield. A high
yield will encourage farmers to cultivate such a variety making it easily available
to processors. A high yielding variety might also satisfy the quantity needed by
the processors for chipping.
In addition, tubers with high yield tend to have high dry matter content
and better quality of finished chips (Tawfik et al., 2002). Accession 13.1.1 having
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
46
the highest yield is among the accessions with high dry matter content and chip
recovery.
Interaction Effect
No significant differences are observed in the interaction of production
sites and potato accessions.
Accession 13.1.1 consistently produced the highest yield in all production
sites except at Longlong where 676089 had the highest yield. Furthermore, most
of the accessions namely 380251.17, Ganza, 573275, and 676089 gained the
highest yield at Englandad while other high yielders were harvested from
Cabutotan and Balili.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
47
Experiment 2: Processing Quality of Potato
Accessions in Different Production Sites
Tuber Characteristics
Tuber Skin
Accessions 380251.17, Ganza, 573275, 676089, and 13.1.1 had yellow
tuber skins in all production sites (Table 5a).
Table 5a. Tuber skin color of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
676070
Pink and
Pink and
Pink and
Pink and
Pink and
Pink and
purplish
purplish
red around purplish
purplish
purplish
red around red around eyes
red around red around red around
eyes
eyes
eyes
eyes
eyes
Ganza
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
285411.22 Purplish-
Purplish-
Purplish-
Purplish-
Purplish-
Purplish-
red
red
red
red
red
red
573275
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
676089
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
5.19.2.2
Yellow
Brownish Yellow
Brownish Brownish Yellow
575003
Yellow
Brownish Brownish Brownish Yellow
Yellow
13.1.1
Yellow
Yellow
Yellow
Yellow
Yellow
Yellow
* Standard character
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
48
Accessions 676070 and 285411.22 also retained their tuber skin color of
pink and purplish red respectively in all sites. The skin color of pink to red potato
tubers is due to the presence of anthocyanin pigments dissolved in the cell sap of
the periderm cells and the outer layer cells of the cortical parenchyma (Van Es
and Hartmans, 1981).
Accession 5.19.2.2, on the other hand, originally had brownish tuber skin
that changed to yellow in Englandad, Sinipsip, and Cabutotan. Similarly,
accession 575003 with yellow tuber skin turned brownish in Longlong, Sinipsip,
and Loo.
Skin color is caused by the presence of certain pigments in the cell sap of
periderm cells (Van Es and Hartmans, 1981). The change in skin color of potato
tubers in some sites might be attributed to higher or lower concentrations of such
pigments making the tuber skin appear darker or lighter. The conditions in the
production sites might have affected pigment production in the periderm.
In addition, tuber skin color is an inherent characteristic of the accession
and is one factor that may affect chip quality. Potato accessions with pink to red
peel for instance, shows up as a dark ring on the slice after chipping. Thus, tuber
skin must be buff (dull yellow) to tan colored (Gould, 1988) to reduce losses.
In terms of skin color, most of the accessions may be chipped even
without peeling. Using accessions 676070 and 285411.22 in chipping is however
a disadvantage due to their pinkish and purplish red tuber skin color.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
49
Tuber Skin Type
Accessions 676070, Ganza, 676089, and 575003 retained their smooth
tuber skins across locations (Table 5b). Accessions 380251.17 and 285411.22, on
the other hand, originally had smooth tuber skins that turned rough in Longlong
and Loo.
Table 5b. Tuber skin type of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Smooth
Rough
Smooth
Smooth
Smooth
Smooth
676070
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
Ganza
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
285411.22 Smooth
Rough
Smooth
Rough
Smooth
Smooth
573275
Smooth
Netted
Smooth
Smooth
Smooth
Netted
676089
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
5.19.2.2
Smooth
Netted
Smooth
Smooth
Netted
Netted
575003
Smooth
Smooth
Smooth
Smooth
Smooth
Smooth
13.1.1
Smooth
Smooth
Smooth
Netted
Netted
Netted
* Standard character
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
50
Similarly, accession 573275 had smooth tuber skin that turned netted in
Longlong and Cabutotan. In contrast, accessions 5.19.2.2 and 13.1.1 had netted
tuber skins that turned smooth in some sites.
The varying skin types of potato tubers across locations might be
attributed to the positioning of cell layers in the periderm of the tubers. Smooth
skinned potatoes (e.g. 575003) have cell layers that remain in position while
netted to rough skinned tubers have cell layers that have become partly detached
giving rise to a rough surface (Van Es and Hartmans, 1981). The conditions in the
sites (e.g. soil type, cultural and environmental conditions, stem maturity, etc.)
might have influenced the positioning of such cell layers (Nolte and Olsen, 2006).
Smooth skin is preferred in tuber for chip processing. Peeling becomes
more efficient and peeling loss is reduced. Accessions with netted peel generally
increases peel loss and decrease chip recovery as a result (Gould, 1988).
Thus, accessions which showed consistently smooth tuber skin might be
more advantageous in decreasing peel loss during processing.
Tuber Flesh Color
The tubers of the different potato accessions had varying flesh colors
across locations (Table 5c). Accessions 380251.17, 573275, and 676089 had
cream tuber flesh but turned to pale yellow in some production sites. Ganza with
pale yellow tuber flesh in most sites turned to cream in Englandad.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
51
Table 5c. Tuber flesh color of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Cream
Cream
Pale
Pale
Cream
Pale
yellow
yellow
yellow
676070
Pale
Pale
Yellow
Yellow
Yellow
Pale
yellow
yellow
yellow
Ganza
Cream
Pale
Pale
Pale
Pale
Pale
yellow
yellow
yellow
yellow
yellow
285411.22 White
White
Pale
Cream
Cream
Cream
yellow
573275
Cream
Pale
Cream
Cream
Cream
Cream
yellow
676089
Cream
Cream
Pale
Pale
Cream
Cream
yellow
yellow
5.19.2.2
Yellow
Yellow
Yellow
Yellow
Pale
Yellow
yellow
575003
Yellow
Pale
Pale
Pale
Pale
Yellow
yellow
yellow
yellow
yellow
13.1.1
Pale
Yellow
Yellow
Yellow
Yellow
Yellow
yellow
* Standard character
Accessions 676070 and 13.1.1, on the other hand, had yellow tuber flesh
that turned to pale yellow in Englandad, Longlong, and Cabutotan. In contrast,
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
52
accessions 5.19.2.2 and 575003 had pale yellow tuber flesh that turned to yellow
in some production sites such as Englandad and Cabutotan.
Finally, accession 285411.22 originally had cream tuber flesh which
turned to white in Englandad and Longlong, and pale yellow in Sinipsip.
Tuber flesh colors (especially of yellow and white tubers) are due to the
presence or absence of carotenoids (Brown et.al., 1993 cited by Edwards et.al.,
2002). Such pigments have higher concentrations in yellower tubers and lower
concentrations in whiter fleshed tubers. Furthermore, it appears that temperature
may increase or decrease the production of these pigments making tuber flesh
color darker or lighter. Thus, the varying flesh colors of the different accessions
across sites might be attributed to the differing concentrations of their pigments
(e.g. carotenoids) as affected by temperature in the production site.
Processors, however, are more concerned with the color of chips after
frying rather than tuber flesh color itself. But, potato tubers with white to yellow
flesh colors are commonly used.
Tuber Shape
Tuber shape of the different accessions varied across locations (Table 5d).
Accessions 380251.17 and 676070 originally had round tubers that became
oblong and elliptic respectively in some sites.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
53
Table 5d. Tuber shape of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Oblong
Oblong
Oblong
Oblong
Round
Elliptic
676070
Round
Elliptic
Round
Round
Round
Oblong
Ganza
Round
Oblong
Oblong
Oblong
Ovate
Obovate
285411.22 Ovate
Round
Round
Oblong
Com-
Round
pressed
573275
Oblong
Obovate
Oblong
Elliptic
Ovate
Oblong
676089
Long
Elliptic
Elliptic
Ovate
Ovate
Elliptic
oblong
5.19.2.2
Ovate
Obovate
Elliptic
Ovate
Ovate
Obovate
575003
Oblong
Oblong
Oblong
Obovate
Oblong
Oblong
13.1.1
Round
Oblong
Oblong
Round
Oblong
Com-
pressed
* Standard character
Ganza, 573275, 676089, and 5.19.2.2 produced ovate tubers in Balili but
tuber shape changed to round, oblong, obovate, and elliptic in some production
sites. Accessions 575003 and 13.1.1 also had oblong tubers that changed from
round to compressed tubers in other production sites.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
54
Finally, accession 285411.22 produced compressed tubers in Balili but
tuber shape changed to round in Longlong, Sinipsip, and Cabutotan; ovate on
Englandad; and oblong in Loo.
Tuber shape is relatively a varietal characteristic. However, growing
conditions may cause variations from this genetically determined trait (Van Es
and Hartmans, 1981). Thus, the differing conditions (e.g. soil type, cultivation,
spacing, etc.) in each site might have also influenced the varying tuber shapes of
each accession.
Shape of tubers is of particular importance in determining the suitability of
potatoes for the chip market. Shape of tubers directly affects the number of slices
per tuber and peel loss (Gould, 1988). Chippers prefer round to oblong shaped
tubers since their shape facilitates the removal of the peel more efficiently and
with less solid loss (Gould, 1988). Moreover, round to oblong shaped tubers tend
to have higher chip recovery. Thus, accessions such as 676070, 13.1.1,
380251.17, and others which were round to oblong had high chip recoveries.
Tuber Eye Depth
Tuber eye depth varies across sites and within accessions (Table 5e). Most
of the potato accessions (e.g. 13.1.1, 5.19.2.2, 676089, etc) had shallow tuber eye
depths that changed from medium to very deep in some production sites.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
55
Accessions 285411.22, on the other hand, had medium tuber eye depths
that became shallow in Longlong but very deep in Englandad and Cabutotan.
Also, the eyes of accession 575003 originally protruded in Balili but sank to
shallow or medium in most locations except Longlong.
Table 5e. Tuber eye depth of the potato accessions grown organically in different
production sites
ACCE-
ENGLAN
LONG-
SINIPSIP LOO
BALILI*
CABUTO
SSION
- DAD
LONG
- TAN
380251.17 Very deep Shallow
Shallow
Shallow
Shallow
Shallow
676070
Medium
Shallow
Medium
Medium
Shallow
Medium
Ganza
Medium
Shallow
Shallow
Shallow
Shallow
Shallow
285411.22 Very deep Shallow
Medium
Medium
Medium
Very deep
573275
Medium
Shallow
Shallow
Shallow
Shallow
Medium
676089
Shallow
Shallow
Shallow
Shallow
Shallow
Shallow
5.19.2.2
Medium
Shallow
Shallow
Shallow
Shallow
Shallow
575003
Medium
Protruding Shallow
Shallow
Protruding Shallow
13.1.1
Shallow
Shallow
Medium
Shallow
Shallow
Shallow
* Standard character
The varying eye depths of potato tubers across sites might be attributed to
the formation of cell layers in the tuber periderm (Van Es and Hartmans, 1981). It
is probable that conditions in the site (e.g. soil type, temperature, relative
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
56
humidity, etc.) might have affected cell layer formation giving rise to shallow or
deep tuber eyes
In addition, eye depth is an inherited characteristic and is often considered
as part of the shape (Gould, 1988). To reduce peel loss, cultivars with shallow eye
depths are preferred for processing. If eyes are too deep, it is necessary to peel
longer and deeper to remove the eye. Further, the eyes should not be colored since
they turn black or brown on chipping and end up as a defect (Gould, 1988).
Thus, the use of accessions 676089 and 13.1.1 may result in reduced peel
loss during chipping since both had consistently shallow eye depth in most sites.
Further, their yellow eye color is consistent with the tuber skin color and thus may
not cause browning on chip.
Dry Matter Content
Effect of Production Sites
Highly significant differences were observed in the dry matter content of
tuber of the potato accessions planted in the different sites (Table 6). Potatoes
grown at Balili significantly had the highest dry matter content of tubers while
those grown at Sinipsip had the lowest. The rest of the accessions grown at
Englandad and Longlong, Loo and Cabutotan had comparable tuber dry matter
contents.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
57
Dry matter content in the tubers is correlated with the potato variety, but
apart from this, soil type, climate, fertilization, pest control, etc. are also of
importance (Hesen and VanderSchild, 1979). Potatoes harvested from Sinipsip,
for instance, had the lowest dry matter content which may be an effect of the high
relative humidity (92.88%) of the site. Excessive water from high rainfall or
relative humidity will often result in tubers with low dry matter (Kellock, 1995).
Table 6. Dry matter content of tubers of the potato accessions grown organically
in different production sites
TREATMENT
DRY MATTER CONTENT
(%)
Production Site (S)
Englandad
20.11b
Longlong
19.83b
Sinipsip
17.42d
Loo
18.70c
Balili
20.78a
Cabutotan
19.01c
Accession (A)
380251.17
18.61c
676070
18.00c
Ganza
18.44c
285411.22
18.42c
573275
20.14ab
676089
20.62a
5.19.2.2
20.47a
575003
19.08bc
13.1.1
20.03ab
S x A
**
CV (%)
9.82
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
58
Furthermore, continuous cloud cover will decrease dry matter by reducing
the photosynthetic rate of the plant. It was observed that Sinipsip was continually
wet and cloudy which might have greatly contributed to the low dry matter
content of the potato accessions.
The high dry matter content of potatoes grown in Balili, on the other hand,
might be due to the optimum environmental condition of the site. Potatoes
normally grow best in areas with a temperature of 15 to 220C (Sano, undated) and
Balili is within the optimum temperature range for growing potatoes.
Effect of Potato Accessions
Highly significant differences are likewise observed in the tuber dry
matter content of the nine accessions used. Accession 676089 and 5.19.2.2
significantly had the highest tuber dry matter content but were comparable to the
tubers of 573275 and 13.1.1. The tubers of the remaining accessions are not
significantly different from each other.
Dry matter content is a strongly inherited characteristic (Kellock, 1995).
Varieties with higher dry matter content (>18%) tend to have higher yields and
better quality of finished chips (Tawfik et.al., 2001). A high dry matter also
results in lower oil absorption of the chip during frying (Hesen and Van der
Schild, 1979). In terms of dry matter alone, all the accessions may be processed
into potato chips since they have tuber dry matter contents of above 18%.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
59
However, for better chip quality, a tuber dry matter content of 20.3 – 22.3% is
best (Mosley and Chase, 1993). Accessions 676089 and 5.19.2.2 may yield better
chips compared with the other accessions.
Interaction Effect
A highly significant interaction is observed between production site and
the different potato accessions on dry matter content. Furthermore, 68% (R-value)
of the differences in dry matter content are due to the interaction of the two
factors, which mean that both factors are important in the selection for chip
processing.
Accessions 5.19.2.2 and 13.1.1 had consistently dry matter content of 18%
and above across all locations (Fig. 1). Although these accessions were exposed to
different organic management practice and environmental conditions, these
accessions still retained high dry matter content for chipping. Dry matter though
affected by different factors is still largely attributed to the genetic make-up of the
accessions.
Furthermore, dry matter content of above 18% was exhibited by all the
accessions harvested from Balili. The other sites revealed accessions with lower
than 18% dry matter content. However, the most accessions (380251.17, Ganza,
573275, 5.19.2.2, 13.1.1) with the highest tuber dry matter content were harvested
from Englandad.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
60
Conditions in the production site also have a bearing on increasing or
decreasing dry matter content of potato accessions. Selection of sites for
production of potatoes intended for chipping is, thus, important.
25
20
15
10
5
0
CABUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 1. Dry matter content (%) of the potato accessions grown organically in
different production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
61
Specific Gravity
Effect of Production Sites
Highly significant differences can be observed in the specific gravity of
the potatoes harvested from the different sites (Table 7).
Table 7. Specific gravity of the potato accessions grown organically in different
production sites
TREATMENT
SPECIFIC GRAVITY
Production Site (S)
Englandad
1.084a
Longlong
1.073abc
Sinipsip
1.060c
Loo
1.067bc
Balili
1.077ab
Cabutotan
1.069bc
Accession (A)
380251.17
1.071ab
676070
1.063b
Ganza
1.068ab
285411.22
1.066ab
573275
1.075ab
676089
1.076ab
5.19.2.2
1.084a
575003
1.069ab
13.1.1
1.074ab
S x A
**
CV (%)
2.26
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
62
Potatoes harvested from Englandad had the highest specific gravity but
comparable with potatoes harvested from Longlong and Balili. Lowest specific
gravity is found in potatoes harvested from Sinipsip.
Specific gravity is a measure of the potato solids or water content. It
influences the processing efficiency, oil absorption of the finished chip, and the
chip recovery (Gould, 1988). Specific
gravity
may
be
influenced
by
environmental factors in the production site (Stark et.al., 2003).
Temperature is the primary factor affecting specific gravity. High
temperature in a site often inhibits starch deposition and decrease specific gravity.
Thus, relatively low temperatures are ideal for increasing specific gravity.
Englandad, Longlong, and Balili had relatively low temperatures ideal for starch
deposition and increased specific gravity.
Sinipsip produced potatoes with low specific gravity which might be
attributed to the high relative humidity and prolonged overcast skies of the site.
High relative humidity may reduce photosynthetic rate to levels below that
required for maximum starch deposition, thus, lowering specific gravity (Stark et
al., 2003).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
63
Effect of Potato Accessions
Accession 5.19.2.2 significantly had the highest specific gravity but
comparable with the rest of the accessions except 676070 which had the lowest
specific gravity.
Generally, high chip recovery is obtained from accessions with high
specific gravity. Such accessions also have been shown to absorb less cooking oil
during the chipping process (Gould, 1988). Thus, accessions 5.19.2.2 including
13.1.1 which had one of the highest specific gravity also had one of the highest
chip recovery and moderately oily chips. It also had one of the highest dry matter
content, thus confirming Gould’s (1988) statement that specific gravity and dry
matter are positively correlated.
Interaction Effect
The highly significant interaction between accessions and production sites
implies that both factors influence specific gravity of potato tubers.
Most accessions with high specific gravity were harvested from
Englandad while those with low specific gravity were taken from Sinipsip (Fig.
2). This shows that environmental conditions in Englandad may have enhanced or
increased the specific gravity of the potato accessions. Relatively low temperature
and relative humidity in the production site may enhance the performance of
potato accessions with increased specific gravity, thus, improve chipping quality.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
64
Accessions 5.19.2.2 and 13.1.1, on the other hand, had the highest specific
gravity. These accessions might yield higher chips and absorb less oil. Selection,
therefore, of a suitable accession and appropriate production site is important in
improving chipping quality.
1
.14
1
.12
1.1
1.08
1 .06
1
.04
1
.02
1
CABUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 2. Specific gravity of the potato accessions grown organically in different
production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
65
Sugar Content
Effect of Production Sites
Sugar content in potatoes is one of the determining factors with respect to
the suitability of a potato variety for the processing industry (Coumou, 1991).
Table 8. Sugar content of the potato accessions grown organically in different
production sites
TREATMENT
SUGAR CONTENT
(0Brix)
Production Site (S)
Englandad
4.16ab
Longlong
4.31a
Sinipsip
3.55c
Loo
4.38a
Balili
3.94abc
Cabutotan
3.72bc
Accession (A)
380251.17
3.72
676070
4.29
Ganza
4.07
285411.22
3.84
573275
4.01
676089
3.96
5.19.2.2
3.91
575003
4.41
13.1.1
3.88
S x A
**
CV (%)
16.98
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
66
The sugar content of tubers largely depends on the genetic make-up of the
variety but may also be affected by the soil type, manuring, weather conditions,
etc. (Hesen, 1985) in the production site. Low sugar content results in better
quality of the processed product.
Potatoes produced from Sinipsip had significantly the lowest sugar content
but were comparable with potatoes harvested from Balili and Cabutotan (Table 8).
The highest sugar content was obtained from potatoes harvested in Loo and
Longlong.
One of the important factors affecting sugar production in tubers is air and
soil temperature. The low sugar content in potatoes from Sinipsip might be
attributed to the low temperature of the place. Low sugar production in tubers
happens at a temperature range of 8-120C (Hesen, 1985). Sinipsip had a
temperature range of 9.50 - 14.120C which might have contributed to low sugar
production in the tubers.
As a general rule, however, any environmental factor that increases
specific gravity also decreases sugars and vice versa (Stark et al., 2003).
Effect of Potato Accessions
No significant differences were observed in the sugar content of the tuber
of the different potato accessions. Tuber of accession 380251.17 had the lowest
sugar content while accession 575003 had the highest.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
67
Sugar content varies considerably between varieties and is an inherited
characteristic as reported earlier. Thus, the different sugar contents of the tubers
of the accessions may be attributed to the genetic make-up.
Sugar content of tubers also plays an important role in the color of the
resulting chips. High sugar content results in discolored or brown chips, which are
unacceptable to consumers (Verma, 1991). Accessions with low sugar content of
0.5 to 2.0% usually results in light colored chips and accessions with sugar
contents higher than 2% are unacceptable for frying (Feltran et al., 2004).
However, there were cases when accessions with as high as 6.690 Brix were used
for frying with no problems on chip quality (Feltran et.al., 2004). Thus, all the
accessions may produce light colored chips with no browning.
Interaction Effect
A highly significant interaction is observed in the sugar content of the
different accessions harvested from the different production sites. Most of the
tubers from accessions with low sugar content were harvested from Sinipsip (Fig.
3). This result may be attributed to the weather condition of the site. Low light
intensity due to cloudy skies and high relative humidity might have decreased
photosynthetic rate and thus sugar production in the tubers. Lowest sugar content
of tubers was exhibited by accession 13.1.1 harvested from Cabutotan. This result
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
68
was confirmed by the light yellow chips with no browning produced from the
accession.
6
5
4
3
2
1
0
CA
BUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 3. Sugar content of the potato accessions grown organically in different
production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
69
Chip Recovery
Effect of Production Sites
Highly significant differences were observed in the chip recovery of the
potatoes harvested from the different sites (Table 9).
Table 9. Chip recovery of the potato accessions grown organically in different
production sites
TREATMENT
CHIP RECOVERY
(%)
Production Site (S)
Englandad
80.58ab
Longlong
77.63ab
Sinipsip
69.85c
Loo
76.62b
Balili
82.74a
Cabutotan
80.83ab
Accession (A)
380251.17
81.41a
676070
81.78a
Ganza
78.04ab
285411.22
69.94c
573275
80.11a
676089
80.03a
5.19.2.2
78.57ab
575003
74.88b
13.1.1
78.07ab
S x A
*
CV (%)
8.62
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
70
Potatoes from Balili produced the highest percentage of chips recovered
but comparable with potatoes from Cabutotan, Englandad, and Longlong.
Potatoes from Sinipsip, on the other hand, produced the least percentage
of chips recovered. Chip recovery is usually attributed to dry matter or specific
gravity (Verma, 1991). Dry matter, on the other hand, is affected by cultural and
environmental conditions of the production site.
High dry matter of tubers usually produces high chip recovery. Thus,
potatoes from Balili which had the highest dry matter also had the highest chip
recovery. Likewise, potatoes harvested from Sinipsip had the lowest chip
recovery which might be attributed to the low dry matter.
Effect of Potato Accessions
Chip recovery among the different accessions had highly significant
differences. Accession 676070 had the highest chip recovery but not significantly
different from the rest of the accessions except for accessions 285411.22 and
575003.
Chip recovery is directly related to the dry matter (Verma, 1991) and
shape of the tuber (Gould, 1988). A high dry matter often results to increased chip
recovery. Round shaped tubers with a smooth surface is also preferred for easier
chipping and higher chip production (Gould, 1988).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
71
Accessions with high chip recovery such as 573275, 676089, 13.1.1, etc
also had relatively high dry matter contents. It is therefore important to choose
accessions with high dry matter for higher chip yield. There are exceptions
however, in accessions that have high dry matter but are prone to damage. Such
accessions become unacceptable for chipping. Damage decreases chip yield.
Interaction Effect
A significant interaction is observed which means that production site and
potato accessions play an important role in increasing chip recovery. Suitable
chipping varieties grown in appropriate production sites must be selected for high
chip recovery.
High chip recovery was observed from potatoes harvested at Longlong
and Balili. Conditions in these sites might have enhanced chip recovery of the
accessions (Fig. 4).
Accession 380251.17 had the highest chip recovery which might be
attributed to its relatively high dry matter content.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
72
100
80
60
40
20
0
CABUTOTA
N
BALILI
LOO
SINIPSIP
LONGLONG
ENGLANDA
D
Figure 4. Chip recovery of the potato accessions grown organically in different
production sites
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
73
Chip Color
Effect of Production Sites
Color is one of the most important factors in the evaluation of tubers for
chipping (Gould, 1988). Potatoes harvested from Longlong, Balili, and Cabutotan
produced light yellow chips while the rest of the accessions produced yellow
brownish chips (Table 10).
Table 10. Chip color of potato accessions grown organically in different
production sites
TREATMENT
CHIP COLOR
Production Site (S)
Englandad
3.00b
Longlong
3.00b
Sinipsip
4.00a
Loo
4.00a
Balili
3.00b
Cabutotan
3.00b
Accession (A)
380251.17
3.00b
676070
4.00a
Ganza
4.00a
285411.22
3.00b
573275
4.00a
676089
3.00b
5.19.2.2
3.00b
575003
4.00a
13.1.1
3.00b
S x A
*
CV (%)
13.99
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
74
The ideal color of chips is usually light yellow to yellow. Chip color may
be influenced by the growing environment, fertilization, cultural practices, or any
factor that will affect sugar content (Gould, 1988). Thus, the light yellow color of
chips produced by the potatoes harvested from Longlong, Balili, and Cabutotan
may be attributed to the weather and farmer’s practices in the sites. It may also be
attributed to the relatively low sugar content of the potatoes harvested from the
sites.
Effect of Potato Accessions
Highly significant differences were observed in the sugar content of the
different accessions. Accessions 380251.17, 285411.22, 676089, 5.19.2.2 and
13.1.1 produced light yellow chips while the rest of the accessions produced
yellow brownish chips.
Chip color is determined to a large extent by the sugar content of the
potato accession. The higher the sugar content the darker is the chip color. A dark
chip color might result to browning and bitter taste, which is unacceptable to
consumers (Kaiyun et al., 2004).
Accessions which produced light colored chips had relatively low sugar
contents (3.72 to 3.960 Brix). The yellow brownish chips were produced from
accessions with high sugar content (4.07 to 4.40 Brix). Dark colored chips are
generally the result of too high sugar content (Gould, 1988).
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
75
Interaction Effect
A
significant interaction between accession and production site on chip
color is observed. This result indicates that the appropriate accession must be
grown in the right production site to produce light colored chips.
All the accessions harvested from Cabutotan produced light yellow chips
while most accessions from Englandad produced yellow brownish chips (Fig. 5).
Furthermore, accession 13.1.1 consistently produced light yellow chips in all
locations except at Balili. In contrast, accession 676070 produced yellow
brownish chips to brown chips.
5
4
3
2
1
0
CABUT
OTAN
BALILI
LOO
SINIPSI
P
LONGL
ONG
ENGLA
NDAD
Figure 5. Chip color of p
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
76
Chip Browning
Effect of Production Sites
There was no browning from the chips produced by the accessions
harvested from Longlong and Cabutotan while slight browning was observed
from the accessions harvested from the remaining production sites (Table 11).
Table 11. Chip browning of the potato accessions grown organically in different
production sites
TREATMENT
BROWNING PATTERN
Production Site (S)
Englandad
Slight
Longlong
None
Sinipsip
Slight
Loo
Slight
Balili
Slight
Cabutotan
None
Accession (A)
380251.17
None
676070
Slight
Ganza
Slight
285411.22
Slight
573275
Slight
676089
Slight
5.19.2.2
None
575003
None
13.1.1
None
Browning is a consequence of high sugar content. The sugars will react
with the amino acids (Maillard reaction) present in the tuber and cause chips to
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
77
fry dark or brown (Gould, 1988). Sugar content, on the other hand, is a
consequence of the condition of the production site.
There were cases, however, of tubers with as high as 6.690 Brix sugar
content which were suitable to frying (Feltran et.al., 2004). Although potatoes
from Longlong had one of the highest sugar content, browning was not observed.
Effect of Potato Accessions
No browning was observed in the chips processed from accessions
380251.17, 5.19.2.2, 575003, and 13.1.1. The tubers from the rest of the
accessions showed chips with slight browning.
Browning is attributed to the amount of sugar in the tuber. A low sugar
content usually limits excessive browning in the final chip (Gould, 1988). This
claim is confirmed by the absence of browning in the chips processed from
accessions 380251.17 and 13.1.1 which had sugar contents of 3.72 and 3.880 Brix,
respectively.
No browning was observed in accessions 5.19.2.2 and 575003 despite
their relatively high sugar content. The absence of browning in these accessions
may be attributed to shorter frying time. It was observed that there were
accessions which easily fry while other accessions took longer time to fry before
fully cooked.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
78
Sensory Evaluation
Effect of Production Sites
Crispiness. Moderately crispy chips were obtained from potatoes harvested from
Englandad, Longlong, Sinipsip, and Loo while crispy chips were produced from Balili and
Cabutotan (Table 12).
Table 12. Sensory evaluation of the potato chips processed from different potato accessions and production sites
CRISPINESS
FLAVOR
TEXTURE
OILINESS
APPEARANCE
GENERAL
ACCEPTABILITY
Production site (S)
Englandad
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Longlong Moderately
Moderately Slightly
Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Sinipsip Moderately
Slightly
Slightly
Moderately Like
Like slightly
crispy
perceptible firm
oily
moderately
Loo Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Balili Crispy Perceptible
Moderately
Moderately Like much
Like much
firm
oily
Cabutotan Crispy
Moderately
Moderately Moderately Like
Like moderately
perceptible firm
oily
moderately
Accession (A)
380251.17
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
676070
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Ganza
Moderately
Moderately Slightly
Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
79
Table 12. continued…
CRISPINESS
FLAVOR
TEXTURE
OILINESS
APPEARANCE
GENERAL
ACCEPTABILITY
285411.22
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
573275
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
676089
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
5.19.2.2
Crispy
Moderately Moderately Moderately Like
Like moderately
perceptible firm
oily
moderately
575003
Crispy
Moderately Moderately Moderately Like
Like moderately
perceptible firm
oily
moderately
13.1.1
Moderately
Moderately Moderately Moderately Like
Like moderately
crispy
perceptible firm
oily
moderately
Crispiness increases with dry matter content, which is in turn easily
affected by conditions of the site. That the potatoes from Balili produced crispy
chips, might be attributed to a high dry matter as affected by the conditions of the
site.
Flavor. Moderately perceptible potato chips were produced from almost
all sites except Sinipsip and Balili. Chips from Sinipsip had slightly perceptible
flavor. The chips had violet pigments with soapy taste which might be attributed
to the cold and high relative humidity of the site.
Chips from Balili had perceptible flavor which might be due to the good
quality tubers harvested from the site.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
80
Texture. Potato chips processed from the different sites were moderately
firm except those harvested from Longlong and Sinipsip, which were slightly
firm. The slightly firm texture of the chips might be due to the low dry matter of
the potato accessions harvested.
Oiliness. All potato chips processed from the different sites were
moderately oily. Oiliness of chips is usually affected by dry matter content of
tubers which is in turn affected by environmental factors.
Appearance. Potato chips produced from potatoes harvested from all
locations were liked moderately except for chips from Balili which were liked
much.
General
acceptability. Potato chips from Englandad, Longlong, Loo, and
Cabutotan were liked moderately. Chips from Sinipsip were liked slightly while
chips from Balili were liked much.
Effect of Potato Accessions
Crispiness. Most of the accessions produced tubers which were
moderately crispy except the tubers of accessions 5.19.2.2 and 575003 which
were crispy. Crispiness is related to the specific gravity or dry matter of the potato
accession. Accessions with high specific gravity tend to produce crispy chips
while those with low specific gravity produce soggy chips (Mosley and Chase,
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
81
1993). Tubers of accessions 5.19.2.2 and 575003 had one of the highest specific
gravity among the other accessions.
Flavor. Tubers of all the accessions had moderately perceptible flavor.
Flavor of a chip may be influenced by the potato accession itself. Sugar content
and other organic compounds in the tuber often affect chip flavor (Gould, 1988).
Texture. Most of the accessions produced tubers with moderately firm
chips except Ganza tubers which produced slightly firm chips. Texture of chips is
influenced by dry matter content of the different tubers. Accessions with high dry
matter often produce firm chips. Ganza which had one of the lowest dry matters
also produced slightly firm chips.
Oiliness. All the accessions produced tubers with moderately oily chips.
Oiliness of chips is often related to specific gravity of the tuber. Accessions
having higher specific gravity have also been shown to absorb less cooking oil
during frying (Gould, 1988). However, the influence of specific gravity of the
different accessions was not clearly seen in terms of chip oiliness. This result may
be attributed to the method of frying done in the study.
Appearance and general acceptability. The chips produced from tubers of
all the accessions were liked moderately.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
82
SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS
Summary
The chip quality of nine potato accessions grown organically in different
production sites was evaluated. The organically grown potato accession with the
best chipping quality and the effect of different production sites to chipping
quality were identified.
The cultural management practices of the organic farmers, relative
humidity and temperature, and soil properties in each site were also identified. It
was observed that each of these factors had a contributory effect to the quality of
the processed chips. For instance, dry matter and sugar content of potato tubers,
which are critical quality factors for processing potatoes, are directly affected by
relative humidity and temperature of the site.
Potatoes from Longlong produced the highest yield. Highest dry matter
content and specific gravity were also observed from potatoes harvested from
Balili and Englandad, respectively. Lowest sugar content, on the other hand, was
exhibited by potatoes harvested from Sinipsip which might be due to the low
temperature of the site.
Potatoes harvested from Balili produced the highest chip recovery but
comparable with those harvested from Englandad, Longlong, and Cabutotan.
Light yellow chips with slight to no browning were produced from potatoes
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
83
harvested in Longlong, Balili, and Cabutotan. Chips which were processed from
potatoes harvested at Balili were liked much by panelists while those processed
from potatoes in Sinipsip were liked slightly.
Accession 13.1.1 had the highest yield while 285411.22 produced the
lowest yield per plant. Accession 676089, on the other hand, had the highest dry
matter content but comparable with those of accessions 573275, 5.19.2.2, and
13.1.1. Accession 5.19.2.2 had the highest specific gravity while the lowest sugar
content was measured from accession 380251.17.
Accession 676070 also had the highest chip recovery but was comparable
with most of the accessions. Light yellow chips with slight to no browning were
produced by most of the accessions. In addition, the chips were moderately crispy
to crispy, moderately oily, and were liked moderately by panelists.
Production site and potato accession interacted significantly to affect dry
matter content, specific gravity, and sugar content. A significant interaction is also
observed on the chip recovery and chip color of potato tubers . This interaction
means that both site and accession are important considerations in organic
growing of potatoes for chipping.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
84
Conclusion
Balili is a good site for organic potato production intended for processing
since it consistently produced potatoes with good chip quality. Potatoes harvested
from Balili had one of the highest yield, dry matter content, specific gravity, and
chip recovery. Furthermore, potatoes from Balili had one of the lowest sugar
content, thus, producing light yellow chips with no browning. The chips were also
liked much by the panelists. Thus, conditions in Balili might have positively
influenced or enhanced the characteristics of the potato accessions for chipping.
Longlong and Cabutotan might also be excellent sites for organic potato
production intended for processing since potatoes harvested from the sites showed
good chipping quality. The potatoes also had high yield and high chip recovery.
Moreover, the chips produced were light yellow but were liked moderately by
panelists.
Among the potato accessions, accession 13.1.1 consistently showed traits
indicating good chip quality. It significantly produced the highest yield in most
production sites which might indicate adaptability to organic production and to
the local conditions of the sites. Furthermore, accession 13.1.1 had one of the
highest dry matter content, specific gravity, and chip recovery. It also had one of
the lowest sugar content, thus, producing light yellow chips with no browning.
Accession 5.19.2.2 also exhibited good chip quality since it had high dry
matter content, specific gravity, and chip recovery. It also produced light yellow
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
85
and crispy chips. However, 5.19.2.2 produced one of the lowest yields per plant,
which might discourage organic farmers from growing it.
Accession 13.1.1 planted in Balili might therefore be the best treatment
combination in producing tubers with good chip quality.
Recommendation
Based on the results of the study, accessions 13.1.1 and 5.19.2.2 are
recommended for chip processing. Balili, Longlong, and Cabutotan may also be
recommended for organic production of potato accessions suitable for chip
processing.
Further evaluation of potato accessions for chipping using more efficient
equipments such as fryers and chippers is also recommended for more accurate
results.
Finally, development of standard organic practices for potato production is
also recommended. Doing this will make evaluation of the adaptability and
chipping quality of potato accessions more accurate.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
86
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92
APPENDICES
Appendix Table 1. Temperature and relative humidity of the different production
sites
PRODUCTION SITE
TEMPERATURE
RELATIVE HUMIDITY
(0C)
(%)
Englandad
October
---
---
November
17.50
86.00
December
15.06
89.00
January
16.88 88.00
MEAN
16.48 87.67
Longlong
October
21.25
82.50
November
21.21
79.75
December
20.12
78.62
January
19.36 82.37
MEAN
20.49 80.81
Sinipsip
November
13.65
92.50
December
13.78
96.00
January
14.12
83.00
February
9.50 100.00
MEAN
12.76 92.88
Loo
November
17.75
86.00
December
17.06
77.00
January
19.88
51.00
February
16.25 87.00
MEAN
17.74 75.25
Chipping Quality of Potato Accessions Grown Organically in Different Production
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93
Appendix Table 1. continued…
PRODUCTION SITE
TEMPERATURE
RELATIVE HUMIDITY
(0C)
(%)
Balili
November
19.05
78.00
December
18.58
79.50
January
17.50
83.75
February
18.30 78.00
MEAN
18.36 79.81
Cabutotan
December
15.00
93.50
January
16.75
78.00
February
15.50
86.50
March
17.50 92.00
MEAN 16.19
87.50
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
94
Appendix Table 2. Total Yield
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 36.76 51.32 48.57 136.65 45.55
676070
17.74 34.38 28.26 80.38 26.79
Ganza
15.71 10.29 10.00 36.00 12.00
285411.22 10.71 12.50 10.71 33.93 11.31
573275
27.78 15.71 39.71 83.20 27.73
676089
41.67 48.68 86.20 176.56 58.85
5.19.2.2
10.29 11.29 16.67 38.25 12.75
575003
15.71 21.67 15.28 52.66 17.55
13.1.1
100.00
22.72
86.36
209.09
69.70
LONGLONG 380251.17
46.67 25.00 170.00 241.67 80.56
676070
65.71 23.75 42.50 131.96 43.99
Ganza
87.78
82.50
106.67
276.94
92.31
285411.22 28.75 10.00 42.86 81.61 27.20
573275
46.67 47.50 46.25 140.42 46.81
676089
136.00
162.50
46.00
344.50
114.83
5.19.2.2
41.43 66.25 45.00 152.68 50.89
575003
22.00 34.29 41.43 97.71 32.57
13.1.1
60.00
35.00
100.00
195.00
65.00
SINIPSIP
380251.17 52.86 28.26 43.18 124.30 41.43
676070
17.89 13.70 17.33 48.92 16.31
Ganza
17.08 9.54 11.25 37.88 12.63
285411.22 9.38 5.45 8.00 22.83 7.61
573275
39.17 10.00 14.17 63.33 21.11
676089
39.40 19.60 11.33 70.33 23.44
5.19.2.2
42.22 17.50 27.04 86.76 28.92
575003
13.25 13.33 16.36 42.95 14.32
13.1.1
67.39 70.45 62.62 200.47 66.82
LOO
380251.17 14.38 42.67 70.71 127.76 42.59
676070
40.62 40.00 20.67 101.29 33.76
Ganza
41.55 10.38 20.50 72.43 24.14
Chipping Quality of Potato Accessions Grown Organically in Different Production
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95
Appendix Table 2. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 10.83 7.00 28.50 46.33 15.44
573275
41.38 37.50 47.50 126.38 42.13
676089
52.19 64.74 36.07 152.99 50.99
5.19.2.2
29.00 45.00 45.62 119.62 39.88
575003
48.67 20.38 13.67 82.72 27.57
13.1.1
61.25
85.77
114.58
261.60
87.20
BALILI
380251.17 44.72 79.41 84.38 208.51 69.50
676070
63.00 56.76 82.63 202.40 67.46
Ganza
40.00 40.83 40.56 121.39 40.46
285411.22
6.33
10.29
10.45
27.08
9.03
573275
19.27 52.37 57.35 128.99 42.99
676089
21.57 58.75 76.11 156.43 52.14
5.19.2.2
0.00
75.00
53.59
128.59
42.86
575003
58.83 21.80 58.70 139.33 46.44
13.1.1
56.00
68.21
119.38
243.60
81.20
CABUTOTAN
380251.17 91.88 57.39 66.90 216.17 72.05
676070
37.10 45.83 49.63 132.56 44.19
Ganza
32.27 51.88 46.52 130.67 43.56
285411.22 60.00 12.50 38.57 111.07 37.02
573275
32.50 17.86 32.86 83.21 27.74
676089
29.83 40.67 75.00 145.49 48.50
5.19.2.2
108.40
45.17
53.33
206.91
68.97
575003
24.54 28.75 24.44 77.74 25.91
13.1.1
157.83
96.67
84.85
339.34
113.11
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
96
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 45.55 80.56 41.43 42.59 69.50 72.05 351.68 58.61
676070 26.79
43.99
16.31
33.76
67.47
44.19
232.51
38.75
Ganza 12.00
92.31
12.63
24.14
40.46
43.56
225.10
37.47
285411.22 11.31 27.20 7.61 15.44 9.03 37.02 107.61 17.93
573275 27.73
46.81
21.11
42.13
43.00
27.74
208.52
34.75
676089
58.85 114.83 23.44 51.00 52.14 48.50 348.76 58.13
5.19.2.2 12.75 50.89
28.92
39.88
42.86
68.97
244.27
40.71
575003 17.55
32.57
14.32
27.57
46.44
25.91
164.36
27.39
13.1.1 69.70
65.00
66.82
87.20
81.20
113.11
483.03
80.51
TOTAL
282.23
554.16
232.59 363.71
452.10
481.05
2365.84
MEAN 31.36
61.57
25.84
40.41
50.20
53.45 43.81
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
2440.84
488.17
9.69** 0.0001
REPLICATION
12 233.40
19.45
0.39ns 0.9657
WITHIN SITE
ACCESSION 8
889.61
111.20
2.21* 0.0334
SITE*ACCESSION 40 1947.44 48.69 0.97ns 0.5368
ERROR
96 45945.79
478.60
TOTAL 161
159144.77
R-square
=
0.71
Coefficient of Variance (CV) = 49.94%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
97
Appendix Table 3. Dry matter content
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 30.00 26.00 17.00 73.00 24.33
676070
15.00 15.50 15.50 46.00 15.33
Ganza
15.50 16.50 28.00 60.00 20.00
285411.22 21.50 18.50 14.00 54.00 18.00
573275
24.00 22.50 21.50 68.00 22.67
676089
20.00 19.00 18.00 57.00 19.00
5.19.2.2
18.50 21.00 30.00 69.50 23.17
575003
16.50 16.00 17.00 49.50 16.50
13.1.1
20.00 21.50 24.50 66.00 22.00
LONGLONG 380251.17 17.50 17.50 17.50 52.50 17.50
676070
20.50 22.00 21.00 63.50 21.17
Ganza
19.00 19.50 19.50 58.00 19.33
285411.22 22.00 18.50 19.50 60.00 20.00
573275
20.00 20.00 19.00 59.00 19.67
676089
23.50 23.50 23.50 70.50 23.50
5.19.2.2
21.00 20.00 17.50 58.50 19.50
575003
18.50 19.00 19.50 57.00 19.00
13.1.1
18.50 19.50 18.00 56.00 18.67
SINIPSIP
380251.17 16.50 16.50 17.00 50.00 16.67
676070
15.50 16.00 16.00 47.50 15.83
Ganza
17.00 17.00 17.00 51.00 17.00
285411.22 17.00 17.00 18.00 52.00 17.33
573275
17.00 16.50 15.50 49.00 16.33
676089
17.00 17.50 17.50 52.00 17.33
5.19.2.2
19.00 19.00 19.50 57.50 19.17
575003
17.50 18.00 18.00 53.50 17.83
13.1.1
19.00 20.00 19.00 58.00 19.33
LOO
380251.17 17.00 17.00 17.00 51.00 17.00
676070
17.00 18.00 17.50 52.50 17.50
Ganza
17.00 17.00 17.00 51.00 17.00
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
98
Appendix Table 3. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 16.50 16.50 17.00 50.00 16.67
573275
21.00 21.00 21.00 63.00 21.00
676089
19.00 19.50 19.00 57.50 19.17
5.19.2.2
20.00 20.00 19.50 59.50 19.83
575003
18.50 19.50 19.00 57.00 19.00
13.1.1
20.00 21.50 22.00 63.50 21.17
BALILI
380251.17 18.00 18.50 18.50 55.00 18.33
676070
21.50 21.50 22.00 65.00 21.67
Ganza
19.00 21.00 19.50 59.50 19.83
285411.22 19.50 20.00 20.00 59.50 19.83
573275
20.50 21.00 21.00 62.50 20.83
676089
21.00 26.50 22.50 70.00 23.33
5.19.2.2
21.50 20.50 20.50 62.50 20.83
575003
21.50 22.50 22.50 66.50 22.17
13.1.1
19.50 20.00 21.00 60.50 20.17
CABUTOTAN
380251.17 18.50 17.50 17.50 53.50 17.83
676070
17.00 16.00 16.50 49.50 16.50
Ganza
17.50 17.00 17.86 52.36 17.45
285411.22 18.50 18.50 19.00 56.00 18.67
573275
19.00 21.50 20.50 61.00 20.33
676089
21.00 21.00 22.00 64.00 21.33
5.19.2.2
19.50 21.00 20.50 61.00 20.33
575003
20.50 19.50 19.50 59.50 19.83
13.1.1
17.50 20.00 19.00 56.50 18.83
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
99
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 24.33 17.50 16.67 17.00 18.33 17.83 111.66 18.61
676070 15.33
21.17
15.83
17.50
21.67
16.50
108.00
18.00
Ganza 20.00
19.33
17.00
17.00
19.83
17.45
110.61
18.44
285411.22 18.00 20.00 17.33 16.67 19.83 18.67 110.50 18.42
573275 22.67
19.67
16.33
21.00
20.83
20.33
120.83
20.14
676089 19.00
23.50
17.33
19.17
23.33
21.33
123.66
20.62
5.19.2.2 23.17 19.50
19.17
19.83
20.83
20.33
122.83
20.47
575003 16.50
19.00
17.83
19.00
22.17
19.83
114.33
19.08
13.1.1 22.00
18.67
19.33
21.17
20.17
18.83
120.17
20.03
TOTAL
181.00
178.34
156.82 168.34
186.99
171.10
1042.59
MEAN 20.11
19.83
17.42
18.70
20.78
19.01 19.31
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
191.01
38.20
33.61** 0.0001
REPLICATION
12 13.64 1.14
0.32ns 0.9850
WITHIN SITE
ACCESSION 8
145.06
18.13
5.04** 0.0001
SITE*ACCESSION 40
378.64 9.47 2.63** 0.0001
ERROR
96 345.44 3.60
TOTAL 161
1073.78
R-square
=
0.68
Coefficient of Variance (CV) = 9.82%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
100
Appendix Table 4. Specific gravity
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 1.260 1.060 1.058 3.378 1.126
676070
1.048 1.050 1.050 3.148 1.049
Ganza
1.050 1.050 1.160 3.260 1.087
285411.22 1.082 1.066 1.043 3.191 1.064
573275
1.096 1.087 1.082 3.265 1.088
676089
1.074 1.067 1.064 3.205 1.068
5.19.2.2
1.066 1.079 1.260 3.405 1.135
575003
1.056 1.053 1.058 3.167 1.056
13.1.1
1.074 1.082 1.098 3.254 1.084
LONGLONG 380251.17 1.061 1.060 1.060 3.181 1.060
676070
1.076 1.085 1.079 3.240 1.080
Ganza
1.069 1.071 1.071 3.211 1.070
285411.22 1.085 1.066 1.071 3.222 1.074
573275
1.074 1.074 1.069 3.217 1.072
676089
1.093 1.093 1.093 3.279 1.093
5.19.2.2
1.079 1.074 1.060 3.213 1.071
575003
1.066 1.069 1.071 3.206 1.069
13.1.1
1.066 1.071 1.064 3.201 1.067
SINIPSIP
380251.17 1.055 1.055 1.058 3.168 1.056
676070
1.050 1.053 1.053 3.156 1.052
Ganza
1.058 1.058 1.058 3.174 1.058
285411.22 1.058 1.058 1.064 3.180 1.060
573275
1.058 1.055 1.050 3.163 1.054
676089
1.058 1.060 1.060 3.178 1.059
5.19.2.2
1.069 1.069 1.071 3.209 1.070
575003
1.060 1.064 1.064 3.188 1.063
13.1.1
1.069 1.074 1.069 3.212 1.071
LOO
380251.17 1.058 1.058 1.058 3.174 1.058
676070
1.058 1.064 1.060 3.182 1.061
Ganza
1.058 1.058 1.058 3.174 1.058
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
101
Appendix Table 4. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 1.055 1.055 1.058 3.168 1.056
573275
1.079 1.079 1.079 3.237 1.079
676089
1.069 1.071 1.069 3.209 1.070
5.19.2.2
1.074 1.074 1.071 3.219 1.073
575003
1.066 1.071 1.069 3.206 1.069
13.1.1
1.074 1.082 1.085 3.241 1.080
BALILI
380251.17 1.064 1.066 1.066 3.196 1.066
676070
1.082 1.082 1.085 3.249 1.083
Ganza
1.069 1.079 1.071 3.219 1.073
285411.22 1.071 1.074 1.074 3.219 1.073
573275
1.076 1.079 1.079 3.234 1.078
676089
1.079 1.080 1.087 3.246 1.082
5.19.2.2
1.082 1.076 1.076 3.234 1.078
575003
1.082 1.087 1.087 3.256 1.085
13.1.1
1.071 1.074 1.079 3.224 1.075
CABUTOTAN
380251.17 1.066 1.060 1.060 3.186 1.062
676070
1.058 1.053 1.055 3.166 1.055
Ganza
1.060 1.058 1.063 3.181 1.060
285411.22 1.066 1.066 1.069 3.201 1.067
573275
1.069 1.082 1.076 3.227 1.076
676089
1.079 1.079 1.085 3.243 1.081
5.19.2.2
1.071 1.079 1.076 3.226 1.075
575003
1.076 1.071 1.071 3.218 1.073
13.1.1
1.060 1.074 1.069 3.203 1.067
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
102
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17
1.13 1.06
1.06
1.06
1.07 1.06 6.44
1.071
676070 1.05 1.08
1.05
1.06
1.08 1.06 6.38
1.063
Ganza 1.09 1.07
1.06
1.06
1.07 1.06 6.41
1.068
285411.22
1.07 1.07
1.06
1.06
1.07 1.07 6.40
1.066
573275 1.09 1.07
1.05
1.08
1.08 1.08 6.45
1.075
676089 1.07 1.09
1.06
1.07
1.08 1.08 6.45
1.076
5.19.2.2 1.14 1.07
1.07
1.07
1.08 1.08 6.51
1.084
575003 1.06 1.07
1.06
1.07
1.09 1.07 6.42
1.069
13.1.1
1.08 1.07
1.07
1.08
1.07 1.07 6.44
1.074
TOTAL
9.78
9.65
9.54
9.61
9.69
9.63
57.90
MEAN 1.084
1.073
1.060
1.067
1.077
1.069 1.072
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
191.01
38.20
33.61** 0.0001
REPLICATION
12 13.64 1.14
0.32ns 0.9850
WITHIN SITE
ACCESSION 8
145.06
18.13
5.04** 0.0001
SITE*ACCESSION 40
378.64 9.47 2.63** 0.0001
ERROR
96 345.44 3.60
TOTAL 161
1073.78
R-square
=
0.43
Coefficient of Variance (CV) = 2.26%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
103
Appendix Table 5. Sugar content
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD
380251.17 3.20 4.20 3.00 10.40 3.50
676070
4.50 4.30 3.00 11.80 3.90
Ganza
5.00 5.40 4.50 14.90 5.00
285411.22 4.50 4.00 5.20 13.70 4.60
573275
4.10 4.10 4.60 12.80 4.30
676089
4.40 3.40 3.20 11.00 3.70
5.19.2.2
4.00 4.10 3.70 11.80 3.90
575003
3.50 4.80 4.20 12.50 4.20
13.1.1
4.30 4.40 4.60 13.30 4.40
LONGLONG
380251.17 2.80 3.40 3.20 9.40 3.10
676070
4.00 5.60 6.40 16.00 5.30
Ganza
4.10 3.40 4.00 11.50 3.80
285411.22 3.80 4.60 4.40 12.80 4.30
573275
3.90 4.80 4.80 13.50 4.50
676089
3.60 4.30 3.80 11.70 3.90
5.19.2.2
3.50 5.80 4.80 14.10 4.70
575003
5.90 4.40 4.30 14.60 4.90
13.1.1
3.90 4.30 4.50 12.70 4.20
SINIPSIP 380251.17 4.20 2.90 4.10 11.20 3.70
676070
4.90 4.10 4.30 13.30 4.40
Ganza
2.80 4.20 3.70 10.70 3.60
285411.22 3.20 3.20 2.60 9.00 3.00
573275
3.30 2.90 4.70 10.90 3.60
676089
2.80 3.20 2.20 8.20 2.70
5.19.2.2
3.30 4.20 3.20 10.70 3.60
575003
3.60 4.40 4.00 12.00 4.00
13.1.1
3.70 3.40 2.70 9.80 3.30
LOO
380251.17 4.00 3.90 4.10 12.00 4.00
676070
5.90 4.00 5.40 15.30 5.10
Ganza
4.60 3.70 4.40 12.70 4.20
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
104
Appendix Table 5. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 4.10 4.30 5.10 13.50 4.50
573275
4.10 3.20 3.90 11.20 3.70
676089
7.60 4.40 3.70 15.70 5.20
5.19.2.2
3.30 4.30 2.80 10.40 3.50
575003
4.30 3.90 6.00 14.20 4.70
13.1.1
5.10 4.10 4.10 13.30 4.40
BALILI
380251.17 4.70 4.00 4.00 12.70 4.20
676070
2.40 4.50 2.40 9.30 3.10
Ganza
3.90 3.60 4.40 11.90 4.00
285411.22 4.20 1.90 3.90 10.00 3.30
573275
3.90 3.80 4.30 12.00 4.00
676089
4.30 3.70 5.00 13.00 4.30
5.19.2.2
4.70 3.90 5.00 13.60 4.50
575003
4.20 3.90 3.90 12.00 4.00
13.1.1
3.60 4.40 4.00 12.00 4.00
CABUTOTAN
380251.17 4.10 3.20 3.90 11.20 3.70
676070
3.90 3.90 3.70 11.50 3.80
Ganza
4.40 3.20 3.90 11.50 3.80
285411.22 2.60 3.40 4.10 10.10 3.40
573275
4.10 3.90 3.80 11.80 3.90
676089
4.20 3.60 3.80 11.60 3.90
5.19.2.2
3.80 3.50 2.50 9.80 3.30
575003
4.70 4.70 4.70 14.10 4.70
13.1.1
2.30 2.70 3.80 8.80 2.90
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
105
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 3.50 3.10 3.70 4.00 4.20 3.70 22.20 3.72
676070 3.90 5.30
4.40
5.10
3.10
3.80
25.60
4.29
Ganza 5.00
3.80
3.60
4.20
4.00
3.80
24.40
4.07
285411.22 4.60 4.30 3.00 4.50 3.30 3.40 23.10 3.84
573275 4.30 4.50
3.60
3.70
4.00
3.90
24.00
4.01
676089 3.70 3.90
2.70
5.20
4.30
3.90
23.70
3.96
5.19.2.2 3.90 4.70
3.60
3.50
4.50 3.30
23.50
3.91
575003 4.20 4.90
4.00
4.70
4.00
4.70
26.50
4.41
13.1.1 4.40
4.20
3.30
4.40
4.00
2.90
23.20
3.88
TOTAL
37.50
38.70
31.90
39.30
35.40
33.40
216.20
MEAN 4.16 4.31
3.55
4.38
3.94
3.72 4.00
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
14.86
2.97
5.90** 0.0056
REPLICATION
12 6.04 0.50
1.09ns 0.3801
WITHIN SITE
ACCESSION 8
6.95
0.87
1.87ns 0.0728
SITE*ACCESSION 40
33.92 0.85 1.83** 0.0086
ERROR
96 44.47 0.46
TOTAL 161
106.24
R-square
=
0.58
Coefficient of Variance (CV) = 16.98%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
106
Appendix Table 6. Chip recovery
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD 380251.17 89.50 93.00 81.30 263.80 87.93
676070
76.90 84.30 83.50 244.70 81.57
Ganza
80.70 71.20 70.40 222.30 74.10
285411.22 76.50 84.10 79.00 239.60 79.87
573275
72.80 86.80 69.00 228.60 76.20
676089
--- --- --- --- ---
5.19.2.2
98.70 74.30 75.30 248.30 82.77
575003
81.70 96.30 72.80 250.80 83.60
13.1.1
79.00 80.30 76.50 235.80 78.60
LONGLONG 380251.17 80.80 75.20 79.70 235.70 78.57
676070
78.80 76.80 81.00 236.60 78.87
Ganza
89.30 83.70 78.30 251.30 83.77
285411.22 66.60 74.80 70.40 211.80 70.60
573275
88.20 81.80 87.10 257.10 85.70
676089
88.40 88.90 84.10 261.40 87.13
5.19.2.2
77.90 82.50 44.30 204.70 68.23
575003
77.20 73.80 57.60 208.60 69.53
13.1.1
77.90 74.90 75.90 228.70 76.23
SINIPSIP
380251.17 80.60 78.40 75.70 234.70 78.23
676070
85.70 74.10 89.10 248.90 82.97
Ganza
78.40 68.90 71.30 218.60 72.87
285411.22 66.50 30.30 65.30 162.10 54.03
573275
---
57.10
76.50
---
---
676089
62.20 73.50 50.60 186.30 62.10
5.19.2.2
81.20 69.30 68.70 219.20 73.07
575003
61.90 69.10 59.50 190.50 63.50
13.1.1
73.40 66.20 82.50 222.10 74.03
LOO
380251.17 75.10 73.30 72.20 220.60 73.53
676070
69.70 85.50 92.50 247.70 82.57
Ganza
72.70 76.60 71.80 221.10 73.70
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
107
Appendix Table 6. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 64.20 72.50 71.80 208.50 69.50
573275
66.90 79.70 87.30 233.90 77.97
676089
80.10 79.60 80.30 240.00 80.00
5.19.2.2
81.60 81.10 72.60 235.30 78.43
575003
72.40 80.60 66.10 219.10 73.03
13.1.1
81.10 79.80 81.60 242.50 80.83
BALILI
380251.17 82.90 85.60 82.00 250.50 83.50
676070
81.70 81.60 84.20 247.50 82.50
Ganza
82.90 81.70 80.10 244.70 81.57
285411.22 71.80 78.80 70.50 221.10 73.70
573275
83.10 83.90 85.00 252.00 84.00
676089
89.40 90.00 86.60 266.00 88.67
5.19.2.2
83.30 83.60 86.90 253.80 84.60
575003
82.30 87.20 82.20 251.70 83.90
13.1.1
88.00 72.30 86.40 246.70 82.23
CABUTOTAN
380251.17 86.50 90.00 83.60 260.10 86.70
676070
85.50 84.40 76.80 246.70 82.23
Ganza
79.10 84.40 83.30 246.80 82.27
285411.22 77.70 71.80 66.30 215.80 71.93
573275
84.20 85.90 86.50 256.60 85.53
676089
84.70 79.40 82.70 246.80 82.27
5.19.2.2
82.40 81.80 88.70 252.90 84.30
575003
73.30 77.50 76.40 227.20 75.73
13.1.1
77.40 77.20 74.80 229.40 76.47
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
108
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 87.93 78.57 78.23 73.53 83.50 86.70 488.46 81.41
676070 81.57
78.87
82.97
82.57
82.50
82.23
490.71
81.78
Ganza 74.10
83.77
72.87
73.70
81.57
82.27
468.28
78.04
285411.22 79.87 70.60 54.03 69.50 73.70 71.93 419.63 69.94
573275 76.20
85.70
66.80
77.97
84.00
85.53
476.20
80.11
676089 ---
87.13
62.10
80.00
88.67
82.27
400.17
80.03
5.19.2.2 82.77 68.23
73.07
78.43
84.60
84.30
471.40
78.57
575003 83.60
69.53
63.50
73.03
83.90
75.73
449.29
74.88
13.1.1 78.60
76.23
74.03
80.83
82.23
76.47
468.39
78.07
TOTAL
644.64
698.63
627.60 689.56
744.67
727.43
4132.53
MEAN 80.58
77.63
69.85
76.62
82.74
80.83 76.53
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE 5
2765.71
553.14
6.61** 0.0036
REPLICATION
12
1004.39
83.70
1.85* 0.0510
WITHIN SITE
ACCESSION 8
1954.61
244.33
5.40** 0.0001
SITE*ACCESSION
39
2986.24
76.57
1.69* 0.0205
ERROR
93 4204.93
45.21
TOTAL 157
12915.89
R-square
=
0.67
Coefficient of Variance (CV) = 8.62%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
109
Appendix Table 7. Chip color
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
ENLANDAD
380251.17 4.00 4.00 3.00 11.00 3.67
676070
4.00 4.00 4.00 12.00 4.00
Ganza
4.00 4.00 3.00 11.00 3.67
285411.22 4.00 4.00 3.00 11.00 3.67
573275
4.00 4.00 5.00 13.00 4.33
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
3.00 4.00 4.00 11.00 3.67
575003
4.00 4.00 3.00 11.00 3.67
13.1.1
4.00 3.00 3.00 10.00 3.33
LONGLONG
380251.17 3.00 3.00 3.00 9.00 3.00
676070
4.00 4.00 4.00 12.00 4.00
Ganza
4.00 3.00 3.00 10.00 3.33
285411.22 3.00 3.00 3.00 9.00 3.00
573275
3.00 3.00 3.00 9.00 3.00
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
4.00 3.00 3.00 10.00 3.33
575003
4.00 4.00 4.00 12.00 4.00
13.1.1
3.00 3.00 3.00 9.00 3.00
SINIPSIP 380251.17 3.00 3.00 3.00 9.00 3.00
676070
6.00 4.00 4.00 14.00 4.67
Ganza
4.00 3.00 3.00 10.00 3.33
285411.22 3.00 4.00 4.00 11.00 3.67
573275
5.00 4.00 4.00 13.00 4.33
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
3.00 3.00 3.00 9.00 3.00
575003
4.00 4.00 3.00 11.00 3.67
13.1.1
3.00 3.00 4.00 10.00 3.33
LOO
380251.17 4.00 4.00 4.00 12.00 4.00
676070
4.00 4.00 3.00 11.00 3.67
Ganza
4.00 4.00 4.00 12.00 4.00
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
110
Appendix Table 7. continued …
PRODUCTION
POTATO
REPLICATION
TOTAL
MEAN
SITE
ACCESSION
I II III
LOO
285411.22 4.00 4.00 3.00 11.00 3.67
573275
3.00 3.00 4.00 10.00 3.33
676089
4.00 4.00 3.00 11.00 3.67
5.19.2.2
3.00 3.00 3.00 9.00 3.00
575003
3.00 3.00 3.00 9.00 3.00
13.1.1
3.00 3.00 4.00 10.00 3.33
BALILI
380251.17 3.00 3.00 3.00 9.00 3.00
676070
3.00 4.00 3.00 10.00 3.33
Ganza
4.00 3.00 3.00 10.00 3.33
285411.22 3.00 4.00 3.00 10.00 3.33
573275
4.00 3.00 4.00 11.00 3.67
676089
3.00 3.00 3.00 9.00 3.00
5.19.2.2
4.00 4.00 3.00 11.00 3.67
575003
4.00 3.00 4.00 11.00 3.67
13.1.1
4.00 3.00 4.00 11.00 3.67
CABUTOTAN
380251.17 3.00 3.00 4.00 10.00 3.33
676070
3.00 3.00 4.00 10.00 3.33
Ganza
3.00 4.00 3.00 10.00 3.33
285411.22 3.00 4.00 3.00 10.00 3.33
573275
3.00 3.00 3.00 9.00 3.00
676089
3.00 3.00 4.00 10.00 3.33
5.19.2.2
3.00 3.00 3.00 9.00 3.00
575003
4.00 3.00 3.00 10.00 3.33
13.1.1
3.00 4.00 3.00 10.00 3.33
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
111
TWO – WAY TABLE
ACCE-
ENGLAN-
LONG- SINIP-
LOO
BALILI CABUTO
TOTAL MEAN
SSION
DAD
LONG
SIP
-TAN
380251.17 4.00 3.00 3.00 4.00 3.00 3.00 20.00 3.00
676070 4.00 4.00
5.00
4.00
3.00
3.00
23.00
4.00
Ganza 4.00
3.00
3.00
4.00
3.00
3.00
21.00
4.00
285411.22 4.00 3.00 4.00 4.00 3.00 3.00 20.00 3.00
573275 4.00 3.00
4.00
3.00
4.00
3.00
21.00
4.00
676089 3.00 3.00
3.00
4.00
3.00
3.00
19.00
3.00
5.19.2.2 4.00 3.00
3.00
3.00
4.00 3.00
20.00
3.00
575003 4.00 4.00
4.00
3.00
4.00
3.00
22.00
4.00
13.1.1 3.00
3.00
3.00
3.00
4.00
3.00
19.00
3.00
TOTAL
34.00
29.00
32.00
32.00
31.00
27.00
185.00
MEAN 4.00 3.00
4.00
4.00
3.00
3.00 3.00
ANALYSIS OF VARIANCE
SOURCE DEGREES
SUM OF
MEAN
F VALUE
Pr > F
OF
SQUARES
SQUARE
FREEDOM
SITE
5
3.36
0.67
3.52* 0.0345
REPLICATION
12 2.30 0.19
0.82ns 0.6283
WITHIN SITE
ACCESSION 8
5.83
0.73
3.13** 0.0035
SITE*ACCESSION
40
16.25
0.41
1.74* 0.0144
ERROR
96 22.37 0.23
TOTAL 161
50.10
R-square
=
0.55
Coefficient of Variance (CV) = 13.99%
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
112
Appendix Table 8. Conversion table for potato dry matter and specific gravity
DMC SG DMC SG DMC SG
14.0 1.043 17.9 1.063 21.7 1.083
14.2 1.044 18.1 1.064 21.8 1.084
14.4 1.045 18.3 1.065 22.0 1.085
14.6 1.046 18.5 1.066 22.2 1.086
14.8 1.047 18.7 1.067 22.4 1.087
15.0 1.048 18.9 1.068 22.6 1.088
15.2 1.049 19.0 1.069 22.8 1.089
15.4 1.050 19.2 1.070 23.0 1.090
15.6 1.051 19.4 1.071 23.1 1.091
15.8 1.052 19.6 1.072 23.3 1.092
16.0 1.053 19.8 1.073 23.5 1.093
16.2 1.054 20.0 1.074 23.7 1.094
16.4 1.055 20.2 1.075 23.9 1.095
16.6 1.056 20.4 1.076 24.1 1.096
16.8 1.057 20.6 1.077 24.3 1.097
17.0 1.058 20.8 1.078 24.5 1.098
17.2 1.059 21.0 1.079 24.7 1.099
17.4 1.060 21.2 1.080 24.9 1.100
17.6 1.061 21.3 1.081
17.8 1.062 21.5 1.082
Source: Kellock, 1995
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
113
Appendix 9. Tuber skin color (www.cip.cgiar.research.org)
Yellowish
Brownish
Pink and purplish around eyes
Purplish red
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
114
Appendix 10. Tuber flesh color (www.cip.cgiar.research.org)
White
Cream
Pale yellow
Yellow
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
115
Appendix 11. General tuber shape (CIP, 1977)
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
116
BIOGRAPHICAL SKETCH
The author was born to Ambrose Sagalla and Lily Sagalla on October 14,
1980. She is the third of four daughters.
Following family tradition, she finished her elementary education at Easter
School, Guisad, Baguio City. She then went to Benguet State University to finish
high school under the Agricultural Science curriculum. She continued her studies
in the same university and finished Bachelor of Science in Agriculture major in
Agronomy.
In August 2001, three months after graduation, she was employed as a
research assistant in one of the foreign funded projects at Northern Philippines
Root Crops Research and Training Center (NPRCRTC). After six months of
working as a research assistant, she resigned to work at the Department of
Agriculture CHARM Project (DA-CHARMP) as an enumerator. She then went
back to NPRCRTC under a different project funded by a Korean. She worked on
the processing of purple yams for 8 months.
Finally, she was hired on January 2003 as an instructor under the
Department of Agronomy, College of Agriculture. She is currently teaching basic
and major subjects in Agronomy.
Chipping Quality of Potato Accessions Grown Organically in Different Production
Sites in Benguet / Esther Josephine D. Sagalla. 2007
Document Outline
- Chipping Quality of Potato
Accessions Grown Organically in Different Production Sites in Benguet
- BIBLIOGRAPHY
- ABSTRACT
- TABLE OF CONTENTS
- INTRODUCTION
- REVIEW OF LITERATURE
- MATERIALS AND METHODS
- RESULTS AND DISCUSSION
- SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS
- LITERATURE CITED
- APPENDICES