鲜切草鱼鱼腩保鲜剂筛选与货架期

Preservative Screening for Prolonged Shelf Life of Fresh-Cut Grass Fish Belly during Cold Storage

以鲜切草鱼鱼腩为原料,选取17种平皿体系条件下对假单胞菌抑菌效果好的保鲜剂对草鱼鱼腩进行保鲜处理,通过感官初筛选出对产品色泽、味道、组织形态、组织弹性影响小的保鲜剂;研究不同初筛得到的保鲜剂处理后冷鲜草鱼肉贮藏期间品质变化,并根据微生物生长曲线构建微生物生长一级模型,通过模型参数的变化定量反映抑菌剂对微生物生长的抑制作用,综合考虑保鲜剂对冷鲜鱼腩品质以及抑菌特性影响,选出草鱼鱼腩处理的最佳保鲜剂;并结合气调包装(50%CO_2+50%N_2)研究保鲜处理后草鱼鱼腩的货架期。结果表明:没食子酸、柠檬酸、鞣酸、磷酸三钾、ε-聚赖氨酸、植酸处理后鱼腩颜色正常,保持原有鱼香味,组织形态和弹性无不好影响;ε-聚赖氨酸处理后品质优于其他组,并在草鱼鱼腩基质上有较好抑菌特性,确定ε-聚赖氨酸为草鱼鱼腩最佳保鲜剂;经ε-聚赖氨酸处理的鲜切鱼腩结合气调包装后置于4℃贮藏时的货架期可达13 d,能较长时间保持鲜切草鱼鱼腩的品质。

Out of 17 preservatives,previously found to be highly effective against Pseudomonas using a plate culture system,the preservatives having little influence on the color,taste,morphology or elasticity of fresh grass carp belly were screened by sensory evaluation. Results suggested that after treatment with gallic acid,citric acid,tannic acid,trimethyl phosphate,polylysine or phytic acid,the color of fish belly remained normal,the flavor was maintained and no negative impact on morphology or elasticity was seen. The quality change of grass carp belly with preservative treatments during cold storage was assessed. A first-order model describing microbial growth was constructed based on the microbial growth curve. The bacteriostatic activity of preservatives was quantitated by model parameters. This study showed that ε-polylysine was the best preservative for grass carp belly. It had less impact on the quality of grass carp belly and exhibited stronger bacteriostatic activity than other preservatives. The shelf life of fresh grass carp with ε-polylysine treatment and modified atmosphere packaging（50% CO2 ＋ 50% N2） when stored at 4 ℃ was 13 days. In conclusion treatment with ε-polylysine can help maintain the shelf life of grass carp.