49B-1 |
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N. KAMIREDDY1, P. B. Kenney1, S. Jittinandana1, S. D. Slider1, R. A. Kiser1, P. M. Mazik2, J. A. Hankins3, and J. Jaczynski1. (1) Div. of Animal & Veterinary Sciences, West Virginia Univ., PO Box 6108, Morgantown, WV 26506-6108, (2) Dept. of Forestry, West Virginia Univ., PO Box 6125, Morgantown, WV 26506-6125, (3) Freshwater Institute, The Conversation Fund, 1098 Turner Rd., Sheperdstown, WV 25443 Lipid oxidation is a major concern in post-mortem processing and subsequent storage of fish. By-products of lipid autoxidation may contribute to texture and flavor deterioration in seafood products. Supplementation of fish feed with antioxidants increases tissue levels of antioxidants and may reduce lipid oxidation depending on postmortem storage and handling practices. The objective was to characterize the impact of high doses of vitamin E supplementation on rainbow trout fillet quality. Rainbow trout were fed a commercial diet or the commercial diet supplemented with 5000 mg á-tocopherol /kg. Fish were fed for 9 weeks, and they were sampled for analyses at weeks 2, 3, 4, 5, 7, and 9. Fillets were placed on styrofoam trays and overwrapped with polyvinyl chloride film. They were stored in the dark at 0°C for 0, 7, and 14 days. Fillets were analyzed for á -tocopherol content, thiobarbituric acid reactive substances (TBARS), pH, color, cook yield, Kramer shear force, psychrotrophic counts, moisture and fat content. Vitamin E supplementation increased fillet á-tocopherol content (p<0.05) from 56.89 mg/kg at week 2 to 156.48 mg/kg at week 9. Storage time had no affect on fillet vitamin E content (p>0.05). At day 0 storage, TBARS value was not affected (p>0.05) by vitamin E supplementation for any sampling week. For fillet pH, significant (p<0.05) diet by storage time and duration of feeding by storage time interactions was observed. Color L* value was not affected by diet, duration of feeding or storage time interactions (p>0.05). Fillets were least red at 14 days of storage (p<0.05), and b* values increased (p<0.05) with storage time. A significant (p<0.05) duration of feeding by storage time interaction was observed for fat content, psychrotrophic counts, cook yield, and shear force. Supplementation of finishing diets with high doses of vitamin E for short duration increases the fillet á-tocopherol concentration.
Session 49B, Aquatic Food Products: General
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