الفهرس 
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Abstract
SUMMARY
Two storage experiments were conducted during two successive
seasons (2013 and 2014) in the laboratory of Vegetable Handling
Research Department, Horticultural Research Institute, ARC at Giza, on
the fruits of cantaloupe (Cucumis melo L. cv. Galia). Fruits were obtained
from private farm in Ismailia governorate. The fruits of the carried
investigation obtained from plants grown under plastic tunnel conditions
during winter seasons. The fruits were harvested at yellow green color
stage. Fruits were selected with uniformity of size, color, weight (700-
750g) and free from any visible damage or defects. The selected fruits
were divided into two principal groups to conduct the two storage
experiments.
5.1. First experiment: Effect of chitosan and potassium permanganate
on quality and storability of cantaloupe fruits
This experiment was carried out on whole cantaloupe fruits to
study the effect of dipped in chitosan at 1000 or 2000 ppm for 3 minutes
or packed with potassium permanganate sachets contained 2.5 or 5 g per
box on quality attributes of fruits during storage for 28 days at 5°C and
90-95% relative humidity in addition to 2 days at 10°C (shelf life).
The results could be summarized as follows:
1- Cantaloupe fruits dipped in chitosan at 2000 ppm or packed with 5
g potassium permanganate led to decrease weight loss percentage
of fruits during all storage periods and shelf life as compared to
other treatments or untreated control.
2- No decayed fruits were observed in cantaloupe fruits dipped in
chitosan at 2000 ppm or packed with 5g potassium permanganate
Mona, M. Haffez (2016), Ph.D. Fac. Agric., Ain Shams Univ.
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till 28 days of the storage at 5°C or 21 days at 5°C plus 2 days at
10°C.
3- Cantaloupe fruits dipped in chitosan at 2000 ppm or packed with
5g potassium permanganate did not exhibit any changes in their
appearance till the 14 days at 5°C plus 2 days at 10°C and gave
good appearance after 21 days at 5°C plus 2 days at 10°C, mean
while fruits dipped in chitosan at 1000 ppm or packed with 2.5g
potassium permanganate showed good appearance after 14 days at
5°C plus 2 days at 10°C and dropped to poor level at the end of
shelf life period.
4- Cantaloupe fruits dipped in chitosan at 2000 ppm were the most
obvious in maintaining fruit firmness at end of the storage period
or shelf life.
5- The highest L values were obtained from fruits dipped in chitosan
at 2000 ppm followed by fruits packed with 5g potassium
permanganate, resulted in lighter color. However, the lowest L
values were obtained from control.
6- The surface color of fruits dipped in chitosan at 2000 ppm
followed by chitosan at 1000 ppm or packed with 5g potassium
permanganate never exceeded light yellow color (the highest b
value) at the end of shelf life condition (28 days at 5°C plus 2 days
at 10°C).
7- Cantaloupe fruits dipped in chitosan at 2000 ppm did not appear
changes in their taste till 21 days of the storage at 5 °C and gave
typical flavor cantaloupe fruits at end of the storage period (28
days). However, during shelf life cantaloupe fruits dipped in
chitosan at 1000 ppm or packed with 5g potassium permanganate
independently gave a slight change in flavor after 21 days of the
Mona, M. Haffez (2016), Ph.D. Fac. Agric., Ain Shams Univ.
116
storage at 5°C plus 2 days at 10°C, while untreated control
resulted in non score after the end of shelf life.
8- Cantaloupe fruits dipped in chitosan at 2000ppm or packed with
5g potassium permanganate gave the higher TSS percentage with
no significant differences between them, after 28 days at 5°C plus
2 days at 10°C of storage, while untreated control gave the lowest
ones at the same period.
9- Cantaloupe fruits treated with various applied treatments had the
highest values of total sugars content with no significant
differences between them in the second season during storage and
in the two seasons during shelf life, while untreated control gave
the lowest ones at the same period.
10- All used postharvest treatments retained more ascorbic acid
content compared to untreated control without significant
differences between them during all storage period at 5°C or shelf
life condition.
5.2. Second experiment: Effect of chitosan, carboxy methyl cellulose,
calcium chloride and wrapping materials on quality and
storability of fresh cut cantaloupe.
Cantaloupe fruits were washed with 500mg/L chlorine solution.
The blossom and stem ends were discarded. Fruits were cut
longitudinally into two halves, seeds were removed and the fruit were
then cut into 8 equal pieces and were dipped into 50 ppm sodium hypo
chloride (PH7) for 30 seconds. The skin was removed and every piece
was approximately 2-2.2 cm thickness and the weight was 70-75 grams.
The samples of fresh cut cantaloupe were randomly divided into 7 groups
then dipped for 3 min. in the following solutions:.
1- 2000 ppm of chitosan (T1).
Mona, M. Haffez (2016), Ph.D. Fac. Agric., Ain Shams Univ.
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2- 4000 ppm of chitosan (T2).
3- 1500 ppm of carboxy methyl cellulose (T3).
4- 3000 ppm of carboxy methyl cellulose (T4).
5- 500 ppm of calcium chloride (T5).
6- 1000 ppm of calcium chloride (T6).
7- Control (distilled water) (T7).
All samples were placed in foam trays and wrapped with the two
types of film (polypropylene or stretch film) and stored at 2.5°C and 95%
RH for 8 days.
The results could be summarized as follows:
1- Fresh cut cantaloupe treated with CaCl2 at 500 ppm or 1000 ppm,
chitosan coating at 2000 ppm and CMC at 1500 ppm then
wrapped with polypropylene film were the most obvious in
reducing the loss of weight during all storage periods.
2- The decayed fruits started to be shown after 6 days of storage in
the two wrapping films, while no decayed fruits were observed in
fruits treated with CaCl2 at 500 ppm or chitosan at 2000 ppm and
then wrapped with polypropylene film during all storage periods.
3- Fresh cut cantaloupe dipped in chitosan at 2000 ppm or carboxy
methyl cellulose at 1500 ppm and wrapped with polypropylene
film showed the best appearance, and kept good appearance at the
end of storage period (8day), while, using CaCl2 at 500 ppm or
CMC at 3000 pm and then wrapped with polypropylene film and
chitosan at 2000 ppm and carboxy methyl cellulose at 1500 ppm
and then wrapped with stretch film rated good appearance after 6
Mona, M. Haffez (2016), Ph.D. Fac. Agric., Ain Shams Univ.
118
days of storage and dropped to the fair level at the end of the
storage.
4- Fresh cut cantaloupe treated with CaCl2 (500 or 1000ppm) or
chitosan coating at 2000 ppm or CMC at 1500 ppm then wrapped
with polypropylene film maintained the fruit texture during
storage in the two seasons. The lowest value of fruit texture was
obtained from untreated control wrapped with stretch film.
5- The highest L values were obtained from fresh cut cantaloupe
treated with CMC at 1500 ppm, chitosan at 2000 ppm and CaCl2
at 500 ppm. The L value remained close to initial value during
storage (high L value), while fresh cut cantaloupe treated with
distilled water (control) had darker color (low L value).
6- Fresh cut cantaloupe coated with CMC at 1500 ppm, chitosan at
2000 ppm or CaCl2 at 500 ppm presented a small decrease in b
values, preserving most of yellow party at the end of storage
period (8 days).
7- Fresh cut cantaloupe coated with CMC at 1500 ppm, chitosan at
2000 ppm or CaCl2 at 500 ppm and then wrapped with
polypropylene film gave the best flavor as compared with other
treatments and control.
8- The highest values of total sugars were obtained from fresh cut
cantaloupe treated with CMC at 1500 ppm, CaCl2 at 500 ppm or
chitosan at 2000 ppm then wrapped with polypropylene film.
While untreated control wrapped with stretch film gave the lowest
ones after 8 days of storage.
9- All fresh cut cantaloupe treatments reduced the incidence of
discoloration compared to control.
, M. Haffez (2016), Ph.D. Fac. Agric., Ain Shams Univ.
119
10- Fresh cut cantaloupe treated with CaCl2 at 500 ppm, CMC at 1500
ppm or chitosan at 2000 ppm and wrapped with polypropylene
film did not show any changes in their color till the end of the
storage (8days). However, CaCl2 at 1000 ppm, CMC at 3000 ppm
or chitosan at 4000 ppm treatments and wrapped with
polypropylene film showed discoloration (slight score). The CaCl2
at 1000 ppm and wrapping with polypropylene gave moderate
score after the same period. The control fruits wrapped with
stretch film showed severe discoloration with the highest score,
11- Fresh cut cantaloupe dipped in CaCl2 at 500 ppm or chitosan at
2000 ppm provided the lowest count in all types of micro
organisms without significant differences between them in the two
seasons followed by CMC at 1500 ppm. While the other used
treatments gave less effect in reducing microbial growth.
12- As for the O2 and CO2 levels inside the package, wrapping with
polypropylene or stretch film and treating with CaCl2 at 1000 ppm
gave the highest value of O2 level and lowest value of CO2 level at
the end of the storage period with no significant differences
between them in the two seasons as compared with other
treatments after 8 days.