SENSORY AND CHEMICAL-CHANGES IN FARMED ATLANTIC SALMON (SALMO-SALAR) DURING FROZEN STORAGE

Farmed Atlantic salmon (Salmo salar) were stored as fillets at -10 and -20 degrees C and whole at -30 degrees C. The most pronounced sensory changes were first recognized by the assessors, when the salmon sampl es were in the oral cavity, and were significant increases in train oi l taste, metal taste, and bitter taste in the fillets. This was shown by mixed model analysis of variance and canonical variates analysis. V olatile lipid peroxidation products such as aldehydes and ketones were identified and quantified in the salmon. For most of the peroxidation products the concentration increased during storage. The content of l ipid hydroperoxides and free fatty acids also increased during storage , and the changes were fastest in salmon stored at -10 degrees C. A de crease in highly unsaturated fatty acids was observed in salmon stored at -10 and -20 degrees C. Peroxide values and the content of free fat ty acids were shown by a partial least-squares analysis to be the best of the instrumental data in describing the sensory changes.