饲料中添加盐对低盐养殖凡纳滨对虾肌肉常规营养成分及质构的影响

Effects of salt addition in feed on muscle nutritional composition and texture of Litopenaeus vannamei cultured in low salinity water

以初始体重为2.70±0.16g的凡纳滨对虾Litopenaeus vannamei为研究对象,在基础饲料中分别添加0(对照组)、1%、2%和4%的食盐,配制成4种实验饲料,在低盐养殖水体中饲养40d,探讨饲料中添加盐对低盐养殖凡纳滨对虾肌肉营养成分及质构的影响。结果表明,随着食盐添加量的升高,凡纳滨对虾虾体蛋白质和灰分含量有增加的趋势,而虾体水分、脂肪有降低的趋势。其中,盐添加量为4%组的蛋白质含量增加极显著(P<0.01),而水分降低亦显著(P<0.05)。在肌肉质构方面,随着饲料中盐添加量的增加,除粘性下降外,其他质构参数都逐渐升高。而且添加4%盐组对虾的硬度、弹性、胶粘性、耐咀性和回复性显著优于其他组(P<0.05),但各组的内聚性无显著差异(P>0.05)。结果表明,饲料中添加盐可以改善低盐养殖凡纳滨对虾肌肉的质构,且当添加量为4%时效果最佳。

Litopenaeus vannamei at an initial body weight of 2.70 ± 0.16g was fed with basal diets respectively supplemented with 0%, 1%, 2%, 4% salt and cultured in low salinity water for 40 days, and the effects of muscle nutritional composition and texture were examined. The results showed that a increased tendency in the content of muscle protein and ash, but a decreased tendency in the moisture and lipid. When 4% salt was added in the feed, the protein content of the muscle was significantly different from the other groups（P〈0.01）, while its moisture content was significantly lower than the other treatments（P〈0.05）. As the addition of salt increased, the indexes of texture also increased except adhesiveness. Hardness, springiness, gumminess, chewiness, resilience were significantly greater than the other groups（P〈0.05）. But the cohesiveness showed no significant difference（P〉0.05）. Results above showed that the muscle quality of the shrimp cultured in low salinity water could be improved by feeding on different levels of salt, and 4% salt in the feed was the optimum level to improve the texture of the shrimp significantly.