不同冻结方式对沙光鱼品质的影响

胡馨月; 张维; 赵行; 李若敏; 周振; 刘冰; 张梦雪; 盘赛昆

doi:10.13386/j.issn1002-0306.2020110184

不同冻结方式对沙光鱼品质的影响

Effects of Different Freezing Methods on the Quality of Synechogobius hasta

摘要

摘要: 为了提高沙光鱼冻藏期间的品质，采用静止空气冻结、送风冻结、液氮速冻处理新鲜沙光鱼，研究不同冻结方式对沙光鱼品质的影响。以蒸煮损失率、挥发性盐基氮（TVB-N）、硫代巴比妥酸值（TBA）、K值、盐溶性蛋白含量、Ca²⁺-ATP酶活性为理化指标并结合冰晶观察和感官评价，考察沙光鱼冻藏过程的品质变化。结果表明：静止空气冻结、送风冻结和液氮速冻通过最大冰晶生成带的时间分别为315、95、8.5 min，液氮速冻耗时最短（P<0.05）。与其它两种冻结方式相比，液氮速冻的机械损伤较小形成的冰晶细小且分布均匀。在冻藏过程中蒸煮损失率、TVB-N值、TBA值、K值均呈上升趋势，液氮速冻上升速率显著低于静止空气冻结和送风冻结。盐溶性蛋白含量、Ca²⁺-ATP酶活性、感官评分均呈下降趋势，静止空气冻结下降最快，液氮速冻下降最慢。冻藏180 d时，液氮速冻沙光鱼的TVB-N值为13.15 mg/100 g、K值为19.78％，达到一级鲜度的标准，送风冻结为二级鲜度，静止空气冻结已不宜食用。液氮速冻能更好地抑制蛋白质冷冻变性、脂肪氧化和微生物的作用，较好地维持沙光鱼的鲜度。因此，液氮速冻优于送风冻结和静止空气冻结，保鲜效果最佳，能更好地保持沙光鱼的品质。

Abstract: To improve the quality of Synechogobius hasta during frozen-storage period, still air freezing, supply air freezing and liquid nitrogen quick freezing were used to treat fresh Synechogobius hasta, so as to study the effects of different freezing methods on the quality of Synechogobius hasta. Combined with ice crystal observation and sensory evaluation, cooking loss rate, total volatile basic nitrogen (TVB-N), thiobarbituric acid value (TBA), K value salt-soluble protein content and Ca²⁺-ATPase activity were used as physical and chemical indexes to investigate the quality changes of Synechogobius hasta during frozen-storage period. The results showed that the time for still air freezing, supply air freezing and liquid nitrogen quick freezing to pass through the maximum ice crystal formation zone was 315, 95 and 8.5 min respectively, and the time for liquid nitrogen quick freezing was the shortest (P<0.05). Compared with the other two freezing methods, liquid nitrogen quick freezing had less mechanical damage, fine and uniform ice crystals. During frozen-storage period, cooking loss rate, TVB-N value, TBA value and K value all showed an upward trend, and the rising rate of liquid nitrogen quick freezing was significantly lower than that of still air freezing and supply air freezing. Salt-soluble protein content, Ca²⁺-ATPase activity and sensory evaluation all showed a downward trend, with the fastest decline in still air freezing and the slowest decline in liquid nitrogen quick freezing. When frozen for 180 days, TVB-N value and K value of liquid nitrogen frozen Synechogobius hasta were 13.15 mg/100 g and 19.78% respectively, which reached the Grade I freshness standard, and the Grade II freshness was determined by supply air freezing and it was unfit to eat by still air freezing. Liquid nitrogen quick freezing can better inhibit protein freezing denaturation, fat oxidation and the effect of microorganisms, and better maintained the freshness of Synechogobius hasta. Liquid nitrogen quick freezing was better than supply air freezing and still air freezing with the best preservation effect, which can better maintained the quality of Synechogobius hasta.