The research was carried out in the laboratories of food science department
at Faculty of Agriculture, Damascus University during the year 2012 to
compare some chemical parameters (moisture،ash, sugars, fat, fibe, protein)
and biological active co
mpounds (total phenols, vitamin C) in fresh strawberry
fruits and strawberry jam. Statistical analysis showed a significant reduction
(p<0.05) in moisture, ash, fat and protein in strawperry jam comparing to fresh
fruits. Total phenols was decreased significantly (P< 0.05) from 2078 mg/100 g
DM in fresh strawberries to 1070 and 962 mg /100 g DM in homemade and
commercial strawberry jam respectively. Also the amount of vitamine c was
decreased from 346 mg /100 gram dry matter in fresh fruits to 45 mg/100 gram
dry matter in locall made jam ،while it was 30 mg/ 100 gram dry matter in
commercial strawberry jam. These were reflected on anthocyanins which was
decreased from 1080 mg/ 100 g DM during processing to 132 and 105 mg/ 100 g
DM in homemade jam and commercial strawberry jam respectively. These
changes reflected in a significant (P< 0.05) decline in the antioxidant activity.
This study was carried out in the laboratories of the Faculty of Agriculture,
Damascus University in 2012 season. Clusters of local yellowish baladi grape
exposed to the concentration (2000 Ppm) of gas SO2 for 3 hours were dried to
moisture conten
t not exceeded 18% by different drying methods (sun drying,
heat drying, solar energy-green house) in the aim of determining their effect on
some chemical indices (total sugar, pH, acidity, solid soluble, non enzymatic
browning), some antioxidants (vitamin C, total phenols) and antioxidant
activity according to 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging
assay. The results showed superiority (p<0.05) of the way solar drying of the
fruits of the grape-treatment with gas SO2 to maintain vitamin C (7.17 mg/ 100
g dry weight) while outperformed the fruits of grapes dried with heat treatment
and gas SO2 in content of phenols (7.24 mg acid Gaelic/ 100 g dry weight).
Results also showed that samples of grapes dried solar and non-treated with gas
SO2 noticeable increase in its activity in the antioxidant, which amounted to
82.42%. The results confirmed that the importance of treatment with gas SO2
prior to the fruits of grapes in reducing (p<0.05) the time required to complete
the drying process, especially in the way of thermal drying to (137 hours)
compared with other transactions.
The main properties(yield of juice, total soluble solid, pH, total acidity, total
sugars), some antioxisant compounds as (vitamin C, carotenoids, total phenol,
anthocyanins), and antioxidant activity measured by DPPH method for some
main Syrian or
ange cultivars (navel, valancia, blood orange, and shamouti)
were investigated. The results showed that valancia was the highest in juice
yield (55.16%), while navel had the highest content of carotenoids(8.68mg/100g)
and the lowest one of vitamin C(31.53mg/100g). Whereas, blood orange was
superior in its content of total phenolic (295.73 mg gallic acid100/g) and
antioxidant activity, (74.833%) among the studied cultivars.
