复合抗氧化剂浸渍处理提升冻藏罗非鱼片品质

为了提高罗非鱼片的冻藏稳定性,以硫代巴比妥酸值(thiobarbituric acid,TBA)、Ca2+-ATPase活性、盐溶性蛋白含量、挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量及质构等为试验指标,进行了维生素E、异抗坏血酸钠及茶多酚等抗氧化剂溶液浸渍处理对冻藏罗非鱼片品质影响的单因素试验,并在单因素试验的基础上进行抗氧化剂复配的正交优化试验。获得了不同的抗氧化剂浸渍浓度对冻藏罗非鱼片品质的影响规律,以主观赋权法对TBA值、Ca2+-ATPase活性、盐溶性蛋白含量、TVB-N和质构(硬度和弹性)5个指标分别赋权后计算各指标的综合评分,确定了各抗氧化剂的较佳浸渍浓度及最佳复合抗氧化剂的组合配方。结果表明,维生素E溶液和异抗坏血酸钠溶液的较佳质量浓度均为6 g/L,茶多酚溶液的较佳质量浓度为4 g/L,在较佳质量浓度条件下各品质指标综合评分与蒸馏水浸泡60 min的对照组相比分别提高了29.11%,18.46%和46.28%。参照成本分析与较优品质结合优化组合的复合抗氧化剂的配方为:异抗坏血酸钠质量浓度为4 g/L、维生素E为质量浓度2 g/L和茶多酚质量浓度为3 g/L,经此配方处理后的冻藏罗非鱼片对应的品质指标分别为TBA值0.1248 mg/kg,Ca2+-ATPase活性3.12μmol/(mg·h),盐溶性蛋白质量分数为77.72 mg/g,均优于单一抗氧化剂的作用,与蒸馏水浸泡60 min的对照组相比,各指标提升幅度为:Ca2+-ATPase活性提高52.20%,盐溶性蛋白质量分数提高16.78%,TBA值下降46.07%。研究结果为复合抗氧化剂的开发及其在冻藏水产品中的应用提供参考。

Antioxidants dipping treatment improving quality of frozen tilapia fillets

In order to improve the stability of frozen tilapia fillets, thiobarbituric acid (TBA) value, Ca2+-ATPase activity, salt-soluble protein content, total volatile basic nitrogen (TVB-N) content and texture were used as the indices. Single-factor experiments that aimed to figure out how antioxidants solution affected the quality of frozen tilapia fillets by dip treating were carried out, and single factors included vitamin E, isoascorbate and tea polyphenols; then an L9(34) orthogonal experiment with antioxidant compounds was performed. The rules on how antioxidant solutions with different concentrations influenced the quality of frozen tilapia, including TBA value, Ca2+-ATPase activity, salt-soluble protein content, TVB-N content and texture were weighted by subjective weighting method, and all modes of combination were ranked, the optimal concentration of antioxidant solutions and the optimal mode of combination were obtained. The results showed that after single-factor experiments,these 3 antioxidants could improve the quality of frozen tilapia and antioxidant properties, and for the concentration of the impregnation solution, the optimal mass concentrations of vitamin E, sodium ascorbate and tea polyphenols were 6, 6 and 4 g/L respectively, and under the conditions above, the quality index of comprehensive evaluation was increased by 29.11%, 18.46% and 46.28% respectively compared to the control group with distilled water soaking for 60 min. The maximum quality index of comprehensive evaluation corresponded to the 4 g/L tea polyphenols, and accordingly the TBA value, the Ca2+-ATPase activity and the mass fraction of salt-soluble protein were 0.1326 mg/kg, 3.00μmol Piprot/h and 75.82 mg/g respectively. Moreover, after the orthogonal experiment, considering cost analysis combined with better quality, the best combination of antioxidant compounds was 4 g/L sodium erythorbate, 2 g/L vitamin E and 3 g/L tea polyphenols, and accordingly the TBA value, the Ca2+-ATPase activity and the mass fraction of salt-soluble protein were 0.1248 mg/kg, 3.12μmol /(mg·h) and 77.72 mg/g, which was better than the effect of any of single antioxidant, and compared to the control group with distilled water soaking for 60 min, the Ca2+-ATPase activity was increased by 52.20%, the mass fraction of salt-soluble protein was increased by 16.78%, and the TBA value was dropped by 46.07%. The composite antioxidant is natural antioxidant formula, its antioxidant property for tilapia fillets has been verified by repeated experiments, which is safe and effective, and the formula is simple and has low cost, so it can be considered to popularization and application in industrial production. Moreover, the results can provide the theoretical basis for the antioxidants application in the frozen aquatic products, which may improve the frozen quality.