| Summary: | The purpose of this research was to determine the quality change in Atlantic Salmon stored at different freezing temperatures for 12 months. Salmon fillets were sliced into ~60g to 65g individual samples (length = 7.3 cm, diameter = 4 cm, thickness = 2 cm), packaged under vacuum, and stored in the refrigerator (3 hours) prior to freezing and pre-frozen samples were also tested. The fresh and pre-frozen salmon were placed randomly at different freezers (freezer 1 = - 7°C, freezer 2 = -12°C, freezer 3 = -18°C, freezer 4 = -29°C and freezer 5 = -77°C for 12 months and sampled monthly. Quality measurements included freeze loss, thaw loss, weight loss, lightness (L*), thiobarbituric acid reactive substances (TBARS), volatile flavor composition (hexanal) (GC-MS), firmness, water holding capacity (WHC), scanning electron microscopy (SEM) analyses (surface pore numbers and size), moisture content, ash, and sensory evaluation. In general, quality was retained to a greater extent in salmon held at -29°C and -77°C during the one-year storage compared to other storage temperatures. The shelf-life prediction was calculated for each quality indicator by the application of a zero-order reaction model. The quality limit of each quality indicator (weight loss and TBARS) was established according to their correlation with the results of sensory evaluation tests. The shelf-life was defined as the earliest date when each characteristic's criteria reached its limit. The shelf-life estimate for fresh Atlantic Salmon was - 7°C (139 days); -12°C (184); -18°C (209); -29°C (305), and -77°C (337). While the shelf-life estimate for pre-frozen Atlantic Salmon was - 7°C (136 days); -12°C (168); -18°C (211); -29°C (281), and -77°C (397).
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