不同温度冻藏对脆肉鲩鱼片品质的影响

Effects of Frozen Storage at Different Temperatures on Qualities of Crisped Grass Carp(Ctenopharyngodon idellus C.et V) Fillets

研究了脆肉鲩鱼片在-18,-25和-30℃下冻藏过程中的理化和感官品质变化.发现冻藏温度对脆肉鲩鱼片的解冻汁液流失率、蒸煮损失率、TBA值和盐溶蛋白含量等理化指标均有显著影响(P<0.05),且随着冻藏时间的延长,差异更明显.冻藏温度愈低,汁液流失率、蒸煮损失率、TBA值增加愈小,盐溶蛋白含量下降也愈小.TPA值的测定显示:经过冻藏的脆肉鲩鱼片的硬度和耐咀性显著增加,回复性显著降低(P<0.05);较低的冻藏温度可使各指标数值的变化趋缓,-30℃下冻藏4周,脆肉鲩鱼片的硬度和耐咀性与新鲜鱼片的相比变化不大.感官评价表明:冻藏降低了脆肉鲩鱼片的感官品质,冻藏过程中鱼肉的质地由脆性向硬实、气味由鱼香味向肉香味转变;冻藏温度的降低会使转变的速率减慢,采用较低的温度(如-30℃)冻藏可以减少感官品质的变化.

The variations of physicochemical parameters and sensory quality of frozen crisped grass carp （ Ctenopha- ryngodon idellus C. et V） fillets during the frozen storage at - 18, -25 and -30 ℃ were investigated. Significant differences （P 〈 0. 05） in the thawing loss, the cooking loss, the TBA value and the salt-extractable protein content were observed during the frozen storage at different temperatures, and more significant differences were found in a longer-time frozen storage. The results indicate that, with the decrease of storage temperature, the thawing loss, the cooking loss and the TBA value increase more slightly, while the salt-extractable protein content less decreases. TPA results show that the hardness and chewiness of the frozen fish fillets increase significantly （P 〈 0. 05 ）, while the resilience decreases significantly （ P 〈 0. 05 ）, that a low storage temperature may result in less change of texture profiles, and that the differences in hardness and chewiness between frozen and fresh fish fillets are not remarkable after the storage at - 30 ℃ for 4 weeks. Sensory analyses indicate that the sensory quality of fish fillets becomes bad due to the frozen storage, that the texture of frozen fish fillets becomes hard, that the odor changes from fish-odor to meat-odor, and that the change rate of sensory quality becomes slow with the decrease of storage temperature, meaning that the storage at a low temperature such as -30 ℃restrains the changes of sensory quality.