冰温技术结合保鲜剂对南美白对虾品质的影响

研究冰温技术结合4- 己基间苯二酚(4-hexylresorcinol，4-HR)等保鲜剂对延缓虾类黑变和保持品质方面的效果。通过正交试验确定保鲜剂的配方(M)，以冻结试验确定冰温贮藏温度，测定贮藏设备的温控范围，通过评定南美白对虾的黑变感官得分，测定多酚氧化酶(PPO)活力、挥发性盐基氮(TVB-N)、pH 值和菌落总数(TBC)等鲜度指标评价保鲜效果差异。结果表明：南美白对虾的冰温带为－ 2.2～0℃，贮藏设备温度波动满足冰温技术要求，M 保鲜剂配方为0.01% 4- 己基间苯二酚+1.5% 柠檬酸+1% 抗坏血酸，冰温能显著减缓TVB-N 值、pH 值和TBC值增加速度，M 配方保鲜剂能有效抑制虾的多酚氧化酶活性和黑变，冰温技术结合M 配方保鲜剂保藏南美白对虾能互补二者优缺点，能显著减低黑变感官得分，PPO 活性、TVB-N、pH 值和TBC 的增长速度。比(4 ± 1)℃冷藏的货架期延长近1 倍。冰温技术结合保鲜剂能有效防止虾类黑变和延长品质货架期。

Effects of Super-chilling Combined with Preservatives on Chemical,Biochemical and Sensory Properties of Pacific White Shrimp

In the present study, we formulated 4-hexylresorcinol, citric acid and ascorbic acid to provide a preservative for inhibiting the darkening of Pacific white shrimps. The formulation was optimized using orthogonal array design. Pacific white shrimps treated with the optimized blend of 4-hexylresorcinol, citric acid and ascorbic acid were kept cold-stored or superchilled for 10 days and the polyphenol oxidase (PPO) activity, total volatile base nitrogen (TVB-N), pH and total bacterial count (TBC) of the shrimps were periodically measured during storage. The results showed that the temperature of super-chilling ranged from 0 to －2.2 ℃, and the temperature fluctuation of a common refrigerator met the requirements of super-chilling. A blend containing 0.01% 4-hexylresorcinol, 1.5% citric acid and 1% ascorbic acid provided an optimal inhibitory effect against the darkening of Pacific white shrimps and could effectively inactivate PPO activity. Super-chilling could make the growth of TVBN, pH and TBC slow down significantly. The combination of super-chilling with the optimized blend gave a mutual complement between them, presented a more significant inhibitory effect against the darkening of Pacific white shrimps and the growth of PPO activity, TVB-N, pH and TBC, and resulted in a 2-fold prolongation of shelf-life when compared with cold storage at (4 ± 1) ℃. These results suggest that super-chilling provides a promising technique for delaying the darkening and prolonging the shelf-life of Pacific white shrimps.