冰衣对冷冻南美白对虾贮藏品质的影响

通过测定－20 ℃冷冻条件下无冰衣组、15%镀冰衣组和25%镀冰衣组南美白对虾的感官评分、解冻损 失、蒸煮损失、挥发性盐基氮（total volatile basic nitrogen，TVB-N）含量、盐溶蛋白含量及肌苷酸（inosine-5’- monophosphate，IMP）关联物各比值，研究镀冰衣处理对冻藏南美白对虾品质的影响。通过分析IMP关联物各比值 （K、Ki、G、P、H及Fr）与主要鲜度指标间的相关性，探讨更适宜作为－20 ℃冷冻条件下镀冰衣南美白对虾品质评 价的指标。结果表明：随着贮藏时间的延长，3 组南美白对虾的解冻损失、蒸煮损失和TVB-N含量均呈明显上升趋势， 盐溶蛋白含量显著下降，25%镀冰衣组南美白对虾的品质始终优于无冰衣组和15%镀冰衣组；根据各指标间的Pearson相 关性分析，K、Ki、G、P、H及Fr值中，K值更适合用于评价该贮藏条件下南美白对虾的整体质量；无冰衣组、15%镀冰 衣组和25%镀冰衣组分别在贮藏第12、16、16周感官不可接受，镀冰衣能够有效延长冻藏南美白对虾的贮藏期。

Effect of Ice Coating on the Quality of Frozen Shrimp (Litopenaeus vannamei)

The effect of ice coating on the quality of frozen shrimp (Litopenaeus vannamei) was assessed by sensory analysis, thawing loss, cooking loss, total volatile basic nitrogen (TVB-N) content, salt-soluble protein and inosinemonpho sphate (IMP)-related compounds. By analyzing their correlations with the main quality indicators, K, Ki, G, P, H and Fr values were screened for their suitability to evaluate the quality of Litopenaeus vannamei during storage. Shrimp samples were left untreated or treated with 15% or 25% ice coating. The results showed that thawing loss, cooking loss and TVB-N content increased significantly with storage time, while salt-soluble protein content showed a substantial decrease. The quality of the 25% ice coating group was always better than that of the control and 15% ice coating groups. Pearson correlation analysis demonstrated that compared to Ki, G, P, H, Fr values, K value was more suitable to evaluate the overall quality of frozen Litopenaeus vannamei. According to sensory analysis, the untreated, 15% ice coating and 25% ice coating groups were evaluated as unacceptable after 12, 16 and 16 weeks of storage, respectively. In conclusion, ice coating could significantly prolong the storage life of Litopenaeus vannamei.