| چکیده انگلیسی مقاله |
The effect of microwave, grilling, steaming and shallow fat frying was evaluated on lipid content and oxidation and also fatty acid composition in S. commerson. Total lipid content was 2.31, 4.02, 2.62, 3.60 and 4.77 % for raw and microwave cooked, grilled, steamed and shallow fat fried samples, respectively. The FFA, PV and TBA content was 4.32 %, 3.00 meq/kg and 0.60 mg/kg in raw samples. There was no significant difference in FFA content between raw sample and grilled, steamed and fried samples and also in PV content between raw and cooked samples. The TBA content increased to 1.58, 1.09, 1.80 and 1.40 mg/kg in microwave cooked, grilled, steamed and shallow fat fried samples, respectively. 23 different fatty acids were found of SFA, MUFA and PUFA groups. The n-6/n-3 ratio was 0.80, 0.80, 0.70 and 0.76 for raw and microwave cooked, grilled, steamed samples, respectively and significantly increased to 2.59 in fried samples. Cooking by different methods affects on total lipid content, fatty acid profile and the lipid stability of fish samples. The changes on chemical characteristics of fish lipid by different cooking methods were in acceptable range and were not detrimental on fish quality. |