壳聚糖对冷藏鲤鱼片品质变化的影响

为了解壳聚糖处理对4 ℃冷藏条件下鲤鱼片品质的影响，测定对照组、T1组（20 g/L壳聚糖＋体积分数0.5%醋酸）、T2组（体积分数0.5%醋酸）鲤鱼片4 ℃冷藏条件下感官分值、菌落总数（total aerobic counts，TAC）、挥发性盐基氮（total volatile basic nitrogen，TVB-N）含量、pH值和生物胺含量等指标的变化，分析壳聚糖对冷藏鲤鱼片品质的影响。结果表明：3 组鲤鱼片的感官分值随着贮藏时间的延长逐渐降低，对照组鲤鱼片在贮藏8 d后感官不可接受，T1组鲤鱼片的总体感官分值高于T2组；3 组鲤鱼片的TVB-N含量在贮藏期间呈增长趋势，贮藏10 d时，对照组鲤鱼片的TVB-N含量与T1、T2组差异显著（P＜0.05），对照组鲤鱼片贮藏10 d时的TVB-N含量达31.37 mg/100 g，而T1组仅为13.07 mg/100 g；T1组鲤鱼片TAC的增长速率显著低于对照组和T2组（P＜0.05）；腐胺、尸胺的含量随着贮藏时间的延长而升高，贮藏后期，T1、T2组鲤鱼片的腐胺含量显著低于对照组（P＜0.05）。壳聚糖的加入可以改善冷藏鲤鱼片的品质，并可将货架期延长2 d。

Effect of Chitosan on the Quality of Common Carp Fillets during Chilled Storage

This study was conducted in order to understand the effect of chitosan on the quality of common carp (Cyprinus carpio) fillets during chilled storage (4 ℃). The fillet samples were divided into three groups which were respectively treated with nothing (control), 20 g/L chitosan + 0.5% acetic acid (T1) and 0.5% acetic acid (T2). Changes in total volatile basic nitrogen (TVB-N) content, biogenic amine content, pH, total aerobic count (TAC) and sensory assessment were examined. Results showed that sensory score decreased gradually as storage time progressed and the sensory quality of the untreated fillets became unacceptable on the 8th day. The overall sensory score of T1 was higher than that of T2. TVB-N content showed an increasing tendency for all groups. T1 and T2 significantly inhibited the increase of TVB-N content (P < 0.05) on the 10th day as compared to control (31.37 and 13.07 mg/100 g for control and T1, respectively). The rate of increase in TAC was significantly lowered in T1 than in control and T2 (P < 0.05). The contents of putrescine and cadaverine increased gradually as storage time progressed; T1 and T2 observably inhibited the formation of putrescine (P < 0.05). These results suggest that chitosan could maintain the freshness and lengthen the shelf life of fillets by 2 days.