4种虾脂肪的提取及其脂肪酸组成的气相色谱分析

Extraction of Lipids from Four Shrimp Species and Analysis of Fatty Acid Composition by Gas Chromatography

采用混合有机溶剂法从南极磷虾、对虾、河虾和罗氏虾中提取脂肪,分别考察提取溶剂、提取时间、料液比和提取温度对虾脂肪得率的影响,确定虾脂肪的最佳提取条件为：提取溶剂为石油醚-乙酸乙酯（2∶1,V/V）、提取时间60 min、料液比1∶5（g/m L）、提取温度50℃。在此条件下南极磷虾、对虾、河虾和罗氏虾的脂肪得率分别为4.39%、2.80%、2.98%和3.30%。采用气相色谱法分析4种虾脂肪的脂肪酸组成,结果表明,4种虾脂肪的不饱和脂肪酸含量较高,且都在60%以上,其中单不饱和脂肪酸的含量为17.08%～34.23%,多不饱和脂肪酸的含量为36.89%～48.28%。4个虾品种间脂肪的脂肪酸组成和含量存在一定的差异,南极磷虾的二十碳五烯酸和二十二碳六烯酸总量最高,达31.27%,而河虾的油酸和花生四烯酸的含量最高。

Shrimp lipids were extracted from Euphausia superba, Penaeuschinesis, Macrobranchium nipponense and Macrobrachium rosenbergii by mixed organic solvents. Effects of extraction solvent, extraction time, ratio of solid to liquid and extraction temperature on the yield of shrimp lipids were investigated. The optimal extraction conditions were obtained as follows： petroleum ether-ethyl acetate（2：1, V/V） as extraction solvent, ratio of solid to liquid 1：5, extraction time 60 min and extraction temperature 50 ℃. Under these conditions, the lipid yields from Euphausia superba, Penaeuschinesis, Macrobranchium nipponense and Macrobrachium rosenbergii were 4.39%, 2.80%, 2.98% and 3.30%, respectively. The fatty acid compos itions of the four shrimp lipids were determined by gas chromatography. The results showed that the contents of unsaturated fatty acids for the four shrimp lipids were all above 60%, consisting of 17.08%–34.23% monounsaturated fatty acids and 36.89%–48.28% polyunsaturated fatty acid. There were some differences in fatty acid composition and lipid contents among the four varieties of shrimps. The total content of DHA and EPA in Euphausia superba was highest（31.27%）, while both C18：1, n9 c and C20：4, n6 were the most abundant fatty acids in Macrobranchium nipponense.