可食性壳聚糖涂膜保鲜大黄鱼品质控制研究

Effects of Edible Coatings Chitosan on the Shelf Life of Large Yellow Croaker (Pseudosciaena Crocea)

为了研究可食性壳聚糖涂膜对大黄鱼贮藏品质的影响,分别用0,1%,1.5%,2%,2.5%的壳聚糖涂膜保鲜大黄鱼,以细菌总数(TVC)、pH值、挥发性盐基氮(TVB-N)、硫代巴比妥酸值(TBA)、K值及感官评分为指标,测定大黄鱼冷藏过程中品质的变化。结果表明:4℃下无壳聚糖涂膜的大黄鱼储藏8 d,菌落总数达到6.04 log cfu/g,超过国标规定的卫生标准;而壳聚糖涂膜处理组细菌生长受到明显抑制,其中1.5%壳聚糖涂膜可使大黄鱼的货架期延长至12 d(TVC值5.98 log cfu/g)。各处理组的pH值、TVB-N、TBA、K值等指标均优于对照组,其中1.5%壳聚糖涂膜时,保鲜效果最好,能较好地保持大黄鱼感官品质。

The effects of edible coatings chitosan on the shelf life of large yellow croaker（Pseudosciaena crocea） during refrigerated storage were investigated.After being killed in slurry ice,large yellow croaker were immersed in 4 ℃ chitosan（0,1%,1.5%,2%,2.5%） for 20 min,and then each sample was drained and packed in polyethylene bag and kept at 4 ℃ for 20 days.Total viable counts（TVC）,pH value,total volatile base nitrogen（TVB-N）,the 2-thiobarbituric acid（TBA）,K-value and sensory characteristics were assessed periodically for the control and the treated groups.The results indicated that the shelf life of large yellow croaker was extended significantly at the storage of 4°C under the chitosan treatment,and the large yellow croaker treated with 1.5% chitosan had significant preservation effects.According to analyses,we could draw a conclusion that chitosan could keep the better quality of large yellow croaker.These conclusions can provide reference for preservation and extend the shelf life of large yellow croaker.