الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Fresh banana peels were divided into two parts. The first part was treated with or without citric acid (1% w/w) and/or sodium-meta-bi-sulfite (200 ppm) then prepared ethanol 95% and/or methanol extracted. Part from the second part had the same treatments as first part was dried at 45° C and other part, as same treatments as first part, was freeze-dried and extracted with ethanol 95% and/or methanol. Potato peels were dried or freeze-dried without any treatments and prepared extracted as the parts of banana peels. Antioxidant properties and total phenolic contents of banana and potato peel extracts were studied. The chemical composition of dried banana and potato peels, total phenolic compounds and free radical scavenging assay by DPPH (1,1 diphenyl-2- picrylhydrazyl radical) of banana and potato peel extracts were measured. Extract capacity to inhibit lipid peroxid-ation measured by two methods: thiobarbituric acid reactive substances (TBARS) and β-carotene bleaching assay. The obtained results showed that freeze-dried banana peels treated by citric acid (1% w/w) extracts exhibited were the strongest antioxidant capacity in different assays. Followed by freeze-dried banana peels treated by sodium-meta-bi-sulfite (200 ppm) and fresh banana peels treated by citric acid (1% w/w) extracts. Results obtained from freeze-dried potato peel extracts showed a slightly higher than those of dried potato peel extracts. The HPLC data indicated that banana and potato peel extracts contained phenolic and flavonoid compounds such as p-coumaric acid, chlorogenic acid, gallic acid, rutin and rosmarinic, responsible for its antioxidant and antibacterial activities. In general, ethanol and methanol extracts showed comparable activity to synthetic antioxidants (BHA). Ethanolic fresh banana peel extracts treated with and/or without citric acid (1% w/w) and dried potato peel extracts were selected for application in beef patties. The effect of banana peel treated with and/or without citric acid (1% w/w) and potato peel extracts on chemical composition, PH value and acid value in beef patties were studied during 30 days storage period at (2-4o C). Effect of banana peel treated with and/or without citric acid (1% w/w) and potato peel extracts on lipid peroxidation monitored by two methods: TBA value and peroxide value. Effect of banana peel treated with and/or without citric acid (1% w/w) and potato peel extracts on some micro-organism such as total bacterial count, Coliform bacteria, Lactic acid bacteria, Yeast and Fungi, Staphylococci Spp. and Salmonella Sp. of beef patties samples were also studied. The results showed that the addition of banana peel treated with and/or without citric acid (1% w/w) and dried potato peel extracts prevented the lipid oxidation and also reduced the micro-organism count had screened in beef patties samples during 30 days of cold storage and banana peel treated with and/or without citric acid (1% w/w) extracts was slightly higher than those of dried potato peel extracts. The results suggested that the natural antioxidant and bioactive compounds of banana and potato peels can be used in production of food.