Linseed oil inclusion in sea bream diets: Effect on fatty acid composition during ice storage

Abstract

Impact on proximate and fatty acids patterns of partial and complete dietary replacement of fish oil (FO) by linseed oil (LO) within on‐growing period was evaluated on marketable‐size gilthead sea bream (Sparus aurata) during 17 days of ice storage. The practical diets were factorially designed as follows: 100% FO (FO), 70% LO + 30% LO (70LO) and 100% LO (100LO). On day 0 of ice storage, there were no significant differences in proximate composition among different treatments. Fish fed FO diet showed high saturated, monounsatured and highly unsaturated fatty acids proportions, whereas fillets from fish fed LO diets increased in 18:3n‐3 content and consequently n‐3 polyunsaturated content. Furthermore, fillet from fish fed FO diets had the highest n‐3/n‐6 ratio. Throughout ice storage no significant fatty acid losses were found, with fish fed LO diets maintaining the highest 18:3n‐3 levels.