辐照结合复配保鲜剂对鲈鱼贮藏品质的影响

为延长大口黑鲈鱼片货架期，将新鲜鲈鱼片分别用无菌蒸馏水（对照）、大蒜素、4 kGy 60Co-γ射线辐照、大蒜素＋辐照、复配保鲜剂A（含0.3 g/100 mL大蒜素、0.3 g/100 mL葡萄籽提取物、1 g/100 mL壳聚糖）＋辐照和复配保鲜剂B（含0.3 g/100 mL大蒜素、0.3 g/100 mL茶多酚、1 g/100 mL壳聚糖）＋辐照处理后，于4 ℃贮藏15 d，考察各处理对鲈鱼片菌落总数、汁液流失率、pH值、硫代巴比妥酸反应物（thiobarbituric acid reactive substance，TBARs）值、总挥发性盐基氮（total volatile basic nitrogen，TVB-N）含量、感官品质及Ca2＋-ATPase活性的影响。结果表明：在贮藏初期，经辐照的鲈鱼TBARs值、TVB-N含量较对照组略高，辐照加速了脂质氧化；而复配保鲜剂结合辐照处理的鲈鱼能有效减缓脂质氧化，减少菌落总数，延缓汁液流失率和pH值的升高，抑制肌原纤维蛋白Ca2＋-ATPase活性的下降；贮藏15 d时，2 种复配保鲜剂结合辐照处理的鲈鱼片菌落总数均未达到6（lg（CFU/g）），仍符合可食用标准，而复配保鲜剂B结合辐照处理组具有最好的保鲜效果；鲈鱼经辐照处理后货架期可延长6 d，而经过复配保鲜剂结合辐照处理均可延长9 d以上，表明辐照与复配保鲜剂在鲈鱼贮藏中具有协同保鲜作用，能有效延长鲈鱼货架期。

Effect of Irradiation Combined with Composite Preservatives on the Storage Quality of Largemouth Bass (Micropterus salmoides)

In order to extent the shelf life of largemouth bass fillets, fillet samples were treated with sterile distilled water as a control, allicin (AL), and 4 kGy 60Co-γ irradiation alone and in combination with AL, composite preservative A (containing 0.3 g of AL, 0.3 g of grape seed extract and 1 g of chitosan per 100 mL of sample) or preservative B (containing 0.3 g of AL, 0.3 g of tea polyphenols and 1 g of chitosan per 100 mL of sample), separately and stored at 4 ℃ for 15 days. The total viable count (TVC), juice loss rate, thiobarbituric acid reactive substances (TBARs) value, pH, total volatile basic nitrogen (TVB-N) content, sensory quality and Ca2+-ATPase activity of the samples were measured during the storage period. The results indicated that at the early stage of storage, the TBARs and TVB-N value of the irradiation group were higher than those of the control group, showing the acceleration of lipid oxidation by irradiation. Combined treatment of the irradiation with each composite preservative could effectively delay lipid oxidation, reduced TVC, retard the increase in juice loss rate and pH, and inhibit the decrease in myofibrillar protein Ca2+-ATPase activity. On day 15, TVC values of the irradiation + composite preservative groups were lower than 6 (lg(CFU/g)), meeting the requirements for consumption. The irradiation combined with preservative B had the best preservation effect. The irradiation alone could extend the shelf life of fish by 6 days compared to more than 9 days when combined with each preservative, suggesting the irradiation and the composite preservatives in combination had a synergistic effect in maintaining the storage quality and prolonging the shelf life of largemouth bass.