Stability of Whole, Filleted, and Minced Trout (Salmo Irideus Gibb) During Frozen Storage

In order to determine the behavior of trout (Salmo irideus Gibb) muscle in frozen storage, five lots (whole, fillets, and minces obtained by extrusion, “mincer” and “cutter”) were made and stored at -200C for one year. During this period the mince, mainly the one made with “cutter”, was more denaturated than the whole trout and fillets. The highest rate of insolubilization was reached by 255 days of storage (45% of soluble protein in minces and 60% in fillets and whole fish). Also a similar difference was noticed in the cooking drip. The variations of protein solubility do not thoroughly explain the changes in objective texture observed up to 30–75 days of storage. So, other parameters may be connected with these changes. On the other hand, after 165 days, the rancidity increase measured by the TBA value is high, especially in the mince although rancid flavor was detected at 120 days of storage.