养殖与野生鮻营养成分和挥发性物质比较

Comparison of Nutrients and Volatile Substances in Muscles between Cultured and Wild Mullet Liza haematocheila

为探究养殖与野生鮻肌肉营养成分的差异,采用常规方法检测并分析“跑道”养殖鮻和野生鮻肌肉基本营养成分、氨基酸、脂肪酸和挥发性成分等指标。试验结果显示,“跑道”养殖鮻肌肉水分含量显著低于野生鮻(P<0.05),粗脂肪含量显著高于野生鮻(P<0.05),灰分和粗蛋白含量差异不显著(P>0.05);“跑道”养殖鮻肌肉中大部分氨基酸含量显著高于野生鮻(P<0.05),必需氨基酸、非必需氨基酸以及氨基酸总量差异显著(P<0.05)。依据氨基酸评分、化学评分,鮻肌肉中第一限制氨基酸均为甲硫氨酸+胱氨酸,第二限制氨基酸均为缬氨酸。必需氨基酸指数为“跑道”养殖鮻(101.39)>野生鮻(82.79)。“跑道”养殖鮻不饱和脂肪酸含量、脂肪酸不饱和度显著高于野生鮻(P<0.05),而饱和脂肪酸含量、二十碳五烯酸+二十二碳六烯酸含量低于野生鮻(P<0.05)。“跑道”养殖鮻和野生鮻分别检测出18种和29种挥发性化合物,野生鮻肌肉中关键风味物质的种类和数量更多,风味更丰富,而“跑道”养殖降低了鮻肌肉中部分呈现不愉悦气味的化合物含量。试验结果表明,“跑道”养殖模式改善了鮻肌肉氨基酸和挥发性化合物的组成。

In order to explore the difference in nutritional and volatile components of cultured and wild marine fish,the proximate nutrient composition,amino acid compositions,fatty acid compositions,and volatile components of the muscles were measured and analyzed between raceway aquaculture system and wild mullet Liza haematocheila.The results showed that there was significantly lower muscular water content in raceway cultured fish than that in wild fish(P<0.05),and significantly higher crude fat content was than that in the wild(P<0.05),without significant differences in ash and crude protein content(P>0.05).The content of most amino acids in the muscle in raceway aquaculture system was significantly higher than that in the wild(P<0.05),while the essential amino acids,non-essential amino acids and total amino acids were significantly different(P<0.05).The amino acid score and chemical score indicated that the first limiting amino acid in mullet muscle was methionine+cystine,and the second limiting amino acid was valine.The raceway aquacultured mullet had higher essential amino acid index(101.39)than the fish in the wild(82.79)did.The farmed mullet had significantly higher unsaturated fatty acid content and fatty acid unsaturation degree than the wild fish did(P<0.05).While the content of saturated fatty acids and eicosapentaenoic acid+docosahexenoic acid were lower in the raceway cultured mullet than those in the wild(P<0.05).18 and 29 volatile compounds were detected in the fish in the raceway aquaculture system and wild,respectively.There were more types and quantities of key flavor substances in the muscle of wild mullet.While mullet cultivated in in-pond raceway aquaculture system led to reduce some of the volatile compounds which presented unpleasant odor compound content.The findings showed that mullet cultivated in the raceway aquaculture system improved the amino acid and volatile compound composition.