壳聚糖、Nisin涂膜在鲢鱼块冷藏保鲜中的应用

Effect of Chitosan and Nisin Coatings on the Shelf Life of Silver Carp (Hypophthalmichthys Molitrix)

研究壳聚糖、Nisin涂膜处理对冷藏条件下鲢鱼块的保鲜作用。在g℃冷藏条件下，采用C。（空气包装，对照）、Cl（经1％壳聚糖涂膜，空气包装）和C2（1％壳聚糖-0．1％Nisin涂膜，空气包装）3种方法处理样品并贮藏15d，定期检测pH值、挥发性盐基氮（TVB—N值）、K值、脂肪氧化（TBARS值）、菌落总数和感官指标。试验结果显示，贮藏过程中C1和C2处理样品组鲢鱼块的pH值、1TvB—N值、K值、TBARS值、茵落总数均显著（P〈O．05、低于对照组Co。综合感官评定结果：Cl和C2的货架期9～12d，相对于对照组Co样品延长3d左右；相对于C1,Nisin复合壳聚糖涂膜C2对鲢鱼块的保鲜效果稍有提高，但对整个货架期的延长无显著作用（P〈0．05）。

This study aimed at determining the effect of chitosan and Nisin coating on shelf-life of silver carp （Hy- pophthalmichthys molitrix） fillets. Silver carp was treated as Co （air packaging, control）, C1 （l%chitosan coating, air packaging） and C2（1% hitosan-0.1% Nisin coating, air packaging）, respectively, and the samples were analyzed periodi- calJy for pH, total volatile base nitrogen（TVB-N）, K value, TBARS, total viable count and sensory evaluation. The re- suits showed that Cl and C2 samples presented a significantly （P〈0.05） lower pH, TVB-N, K value, TBARS value and total viable count than those of the control ones. According to the results of sensory evaluation, the shelf-life of the C1 and C2 samples were about 9-12 days while the control one only 6 days, indicating that chitosan coatings were effective in extending for an additional 3 days the shelf life of the silver carp. Comparing with C1, the samples treated with com- bined chitosan and Nisin presented an indistinctively longer shelf-life than those coated by chitosan only.