采用31P核磁共振光谱法快速测定坚果类食品中的6种磷脂。样品经碾碎后,采用三氯甲烷-甲醇混合溶剂提取其中的脂类物质,用氮气流挥干溶剂后,将残渣直接溶于三氯甲烷-甲醇(2+1)氘代溶剂进行核磁分析。6种磷脂的质量浓度的线性范围为0.05~2.5 g·L-1。方法加标回收率在96.0%以上,测定值的相对标准偏差(n=5)小于5%。实际样品分析结果显示,磷脂酰胆碱、磷脂酰乙醇胺和磷脂酰肌醇为坚果类食品中3种主要磷脂,含量分别为1.72~2.92 mg·g-1,0.61~2.20 mg·g-1和0.72~4.24 mg·g-1。

31P-NMR was applied to the determination of 6 phospholipids in nuts. After the sample was crushed, lipids were extracted with a mixture of chloroform and methanol. The extract solution was dried by N2 blowing, then the residue was dissolved in deuterated chloroform-methanol (2+1) solution and analyzed with 31P-NMR directly. The linearity ranges of 6 phospholipids were 0.05-2.5 g·L-1. Recovery rates obtained by standard addition method were more than 96.0%, with RSDs (n=5) less than 5%. Results showed that phosphatidylcholine, phosphatidylinositol and phosphatidylethanolamine were the main phospholipids in nuts, with content in the ranges of 1.72-2.92 mg·g-1, 0.61-2.20 mg·g-1 and 0.72-4.24 mg·g-1, respectively.