摘要：
研究前期筛选了3种对凡纳滨对虾多酚氧化酶具有较好抑制效果的巯基化合物(L-半胱氨酸、还原性谷胱甘肽和N-乙酰-L-半胱氨酸),为进一步探讨它们对凡纳滨对虾的防黑变效果,以无菌水、亚硫酸钠和4-己基间苯二酚(4-HR)处理为对照,利用黑变评分、相对灰度值、感官评价、菌落总数、挥发性盐基氮和pH值等指标评价其对4°C贮藏的凡纳滨对虾的防黑变和保鲜效果.结果表明:与无菌水处理组相比,3种巯基化合物对凡纳滨对虾均具有较好的防黑变效果,当贮藏到10 d时,L-半胱氨酸、还原性谷胱甘肽和N-乙酰-L-半胱氨酸处理虾体的黑变评分分别为3(±0.81)、3(±0.81)和5.33 (±0.73)分,均未超过最大可接受值6分,而且与亚硫酸钠的防黑变效果相当,但弱于4-HR;但3种巯基化合物对凡纳滨对虾不具有明显的保鲜效果.因此,3种巯基化合物可代替亚硫酸钠作为有效的虾类黑变抑制剂,但是如果要同时对虾进行保鲜,必须与其他抑菌物质复配.%Litopenaeus vannamei is one of the very popular seafoods with higher nutritional value. However, melanosis of the shrimp occurs easily because polyphenol oxidase (PPO) catalyses a series of biochemical reactions during storage and processing after capture. Although melanosis does not affect the nutritional value of shrimp,it seriously affects shrimp sensory quality and commercial value,then causes severe economic loses. At present,sulfite and 4-hexylresorcinol (4-HR) are widely used to prevent melanosis of the shrimps commercially. However,some researches show that they have potential hazards to human health and have been prohibited to use as food additives in many countries. Therefore,it is very important to develop green,safe and effective melanosis inhibitors of shrimps. In the previous studies,three sulfydryl compounds (L-cysteine,glutathione and N-acetyl-L-cysteine) had better inhibitory effects on PPO from L. vannamei. In this study,regarding sterile water,sodium sulfite and 4-HR treatment as controls,melanosis inhibition of three sulfhydryl compounds on L. vannamei was explored during refrigerated storage. The results show as follows:Compared with the sterile water treatment,three sulfydryl compounds have better inhibitory melanosis effect on L. vannamei. Three sulfydryl compounds have the same inhibitory melanosis effect on L. vannamei with sodium sulfite,but less than that of 4-HR. Three sulfydryl compounds do not have obvious preservation effect on L. vannamei. Therefore,three sulfhydryl compounds can replace sodium sulfite as effective melanosis inhibitors of shrimps. They must be mixed with other antibacterial substances if shrimps need to be preserved meanwhile.
