冰衣结合茶多酚对南美白对虾冻藏中品质变化的影响

为探究不同成分冰衣对南美白对虾冻藏期间品质变化规律的影响,将南美白对虾分别镀上水冰衣和茶多酚冰衣-18℃冻藏24周,对其色泽、蒸煮损失率、水分分布、水溶性蛋白质量分数、二硫键质量摩尔浓度、羰基质量摩尔浓度和内源荧光强度等指标进行研究。结果表明:随着冻藏时间的延长,南美白对虾虾肉保水性下降,水分由结合水逐渐向不易流动水及自由水迁移,对照组、水冰衣组、茶多酚冰衣组的蒸煮损失率在第24周分别上升至16.47%、13.42%和14.03%;随着时间增加,处理组与对照组的色泽变化具有显著差异(P0.05);水溶性蛋白质量分数、二硫键质量摩尔浓度、羰基质量摩尔浓度增加,对照组、水冰衣组、茶多酚冰衣组的内源荧光强度分别降低了45.86%、37.78%和35.38%,处理组蛋白变性程度均显著优于对照组(P0.05),且添加茶多酚的冰衣能更好的降低蛋白氧化程度。

Effects of glazing with tea polyphenols on the quality characteristics for Pacific white shrimp (Litopenaeus vannamei) during frozen storage

Freezing storage is common option among the existing methods of long term preservation for shrimp products.Glazing, which is used to reduce the impact on quality resulting from cold storage deterioration, becomes an important quality and economic factor in seafood industry.In order to elucidate the influence of glazing on the Pacific white shrimp''s quality during the frozen storage, the shrimp are glazing with water or tea polyphenols.The color, cooking loss, water distribution, water soluble protein content, disulfide bond content and carbonyl content and fluorescence intensity of shrimp are determined.The results showed that:With the extension of storage time, its water holding property is decreasing.And the cooking losses in 24 weeks were increased to 16.47%, 13.42% and 14.03%;The color of treatment group and control group has significant difference (P<0.05);Disulfide bond content and carbonyl content are increasing;The fluorescence intensity was decreased to 45.86%, 37.78% and 35.38% at 24 weeks;The protein denaturation of the treatment group are significantly better than the control group (P<0.05), and the addition of tea polyphenols could better reduce the degree of protein oxidation.