Changes in Texture, Water Holding Capacity, Colour and Thermal Stability of Frozen Cod (Gadus morhua) Fillets: Effect of Frozen Storage Temperature

摘要

Frozen storage of individually packed cod fillets for up to 13 months caught in the Barents Sea revealed differences in quality caused by storage temperature. While at -14°C already after 7 months pronounced changes in texture parameters and water holding capacity were observed, changes of quality parameters at -28 °C after 13 months storage were negligible. Changes in same parameters of single and double frozen samples stored at -20°C were between both. Numerous linear correlations could be observed between instrumentally measured parameters and storage time. However, frequency of correlations was decreasing with decreasing storage temperature. Deviating from this behaviour, changes in redness with storage time were more wave-like instead of linear. Changes in DSC curves were found for the myosin peak, whereas the actin transition was almost unaffected. Compared with earlier results obtained on Baltic Sea cod the transition temperatures for both myosin and actin shifted to lower temperatures indicating the influence of environmental conditions on thermal stability of muscle proteins.