الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
In this study, ethanol (50 and 100%), methanol (70 and 100%), acetone (70 and 100%), chloroform 100% and water extract of grape seeds were evaluated for their antioxidant and antimicrobial activities. Extraction yield of grape seeds ranged from 6.0 to 14.50% depending on organic solvent type. Grape seed methanol 70% and ethanol 50% extract had significantly higher total phenolic (9.501 and 8.949 mg gallic acid/g), total flavonoids (6.707 and 6.398 mg quercetin /g) and antioxidant activity (702.37 and 636.50 μMolTrolox eq/gm), respectively than other grape seed extracts. While, grape seeds water extract showed the lowest total phenolic, flavonoids compounds and antioxidants activity. Twenty one phenolic and nine flavonoid compounds were identified by HPLC technique in each one of grape seed extracts. P-OH-benzoic was the highest phenolic compound in GS methanol 70% extract. Pyrogallol was the highest phenolic compound in GS ethanol 50% extract. Alpha-coumaric and cinnamic were present in trace amount in grape seed methanol 70% and ethanol 50% extract, respectively. Moreover, hesperidine was the major flavonoid compound in all grape seed extracts followed by naringin, rutin and quercetrin. Also, 50% grape seeds ethanol extract had higher antimicrobial activity against all studied microorganisms. Grape seed extracts could be arranged in descending order according to their antimicrobial potency as: ethanol 50% ˃ acetone 50% ˃ ethanol 100% ˃ acetone 100% ˃methanol 70% ˃ chloroform 100%˃ water. Grape seeds ethanol 50% extract was selected for improving the quality attributes and shelf-life of chicken fillets and chicken burgers during storage at 5±1ºC. Soaking of chicken breast fillets in different concentrations of grape seeds ethanol extract for other chicken fillets samples led to increase moisture content and decrease
crude protein, crude fat and total ash contents. By increasing cold storage period, moisture and crude protein contents significantly decreased but crude fat, total ash, total volatile nitrogen and thiobarbituric acid of both chicken fillets and chicken burgers were significantly increased. Moreover, water holding capacity, plasticity and cooking parameters of chicken breast fillets and chicken burgers were improved by soaking chicken fillets in different concentrations of GSEE during cold storage. Chicken fillets treated with different concentrations of GSEE and stored at 5±1°C for 16 days had lower total bacteria psychrophilic bacteria, Staphylococcus aureus, coliform bacteria, and total yeast and mold counts. Also, burgers treated with GSEE were lower in total bacterial, psychrophilic bacteria and yeast and mold counts than control sample. The microbial count of chicken breast fillets and chicken burgers were decreased by increasing GSEE concentration. All chicken breast fillets samples whether untreated or treated with various concentrations of grape seeds ethanol extract were completely free from Salmonella spp. either at zero time or along cold storage period. Also, all chicken burgers were completely free from coliform bacteria, Staphylococcus aureus and salmonella spp. either at zero time or during cold storage period. Moreover, soaking of chicken breast fillets in different concentrations of GSEE led to significant (p≤0.05) improvement in taste, odor and color immediately after processing and during cold storage period. While, texture and overall acceptability were slightly improved. Chicken fillets treated with 0.3% GSEE and burger sample treated with 0.5% GSEE had higher overall acceptability immediately after processing and during cold storage periods.
Key words: Grape seeds, Extractions, Antioxidant activity, Antimicrobial activity, Chicken fillets, Chicken burger, Chemical, Physical, Microbilogical properties and Organoleptic evaluation.