不同温度冻藏对军曹鱼片品质的影响

研究不同冻藏温度(－ 10、－ 18、－ 30℃)对军曹鱼片部分理化指标、质构特性及感官品质的影响。结果表明，冻藏温度对军曹鱼片的解冻汁液流失率、蒸煮损失率、盐溶蛋白含量、Ca2+-ATPase 活性和TBA 值(硫代巴比妥酸)均有显著性影响(P ＜ 0.05)。冻藏时间越长、冻藏温度越高，汁液流失率、蒸煮损失率、TBA 值增加越大，盐溶蛋白含量、Ca2+-ATPase 活性下降也越多，即保水性降低、蛋白质变性程度增大、脂肪氧化加快。TPA(质构分析)发现军曹鱼片的硬度和耐嚼性随着冻藏时间的延长均呈显著增加趋势(P ＜ 0.05)，而回复性则显著下降(P ＜ 0.05)；冻藏温度越低，相应的硬度和耐嚼性就越小，而回复性则越大。感官评价表明冻藏导致军曹鱼片的品质下降，冻藏温度越高，品质劣变就越严重。采用较低的温度(－ 30℃)冻藏可以最大限度的保持军曹鱼片的品质。

Effect of Frozen Storage Temperature on the Quality of Rachycentron canadum Fillets

Rachycentron canadum fillets were stored at －10, －18 or －30 ℃ for a 90-day period of time in order to investigate the effect of different frozen storage temperatures on the physicochemical properties, textural characteristics and sensory attributes of Rachycentron canadum fillets. Temperature had a significant effect (P＜0.05) on thawing loss, cooking loss, saltextractable protein content, Ca2+-ATPase activity and TBA value during frozen storage. Thawing loss, cooking loss and TBA value increased, while salt-extractable protein content and Ca2+-ATPase activity decreased with increasing storage period and temperature. This suggests the decrease of water holding capacity, the increase of protein denaturation degree and the acceleration of lipid oxidation. The texture profile analysis (TPA) showed that the hardness and chewiness of frozen fish fillets increased significantly (P＜0.05), while the resilience decreased significantly (P＜0.05) with prolonged storage period; the hardness and chewiness decreased while the resilience value increased with decreasing temperature. The results of sensory analysis that the sensory quality of fish fillets deteriorated due to frozen storage and that higher temperatures resulted in aggravated quality deterioration. The optimal storage temperature was － 30 ℃.