NMR氢谱法分析市售奶油中的脂肪酸

在对奶油CDCl₃提取物¹H-NMR图谱主要信号峰归属的基础上,采用NMR氢谱法对市售的28个奶油中主要脂肪酸的相对摩尔含量进行了测定。结果显示,所测28个市售奶油中亚麻酸的相对摩尔含量为0.55%¹.00%,亚油酸为0.59%³.20%,丁酸为9.56%¹2.59%,油酸为13.18%²1.01%,共轭亚油酸为0.34%¹.10%,饱和脂肪酸为74.95%⁸4.44%,其中人体必需脂肪酸总量（亚麻酸、亚油酸、共轭亚油酸）为2.16%⁴.35%。此外,利用1D-TOCSY、J-RES、¹H-¹H COSY等多种NMR技术,鉴定出奶油中含有的1-戊烯成分,实现对食品复杂体系中非目标物的快速定性分析。 

~1H-NMR analysis of fatty acid composition of commercially available butter

In this study,the main signal peaks of~1 H nuclear magnetic resonance spectroscopy(~1H-NMR) in CDCl_3 extracts of butter were assigned by a few different NMR experimental methods.Then the fatty acid composition of butter were determined upon analysis of~1H-NMR spectra. Twenty-eight brands of commercially available butter were determined in the study. The results showed that the relative molar contents of linolenic acid,linoleic acid,butyric acid,oleic acid,conjugated linoleic acid( CLA) were 0.55% ~1.00%,0.59% ~3.20%,9.56% ~12.59%,13.18% ~21.01%,0.34% ~ 1.10%,and the contents of saturated fatty acids( SFA) and essential fatty acid( linolenic acid,linoleic acid,CLA) were 74.95% ~84.44% and 2.16% ~4.35%.In addition,1-pentene in CDCl_3 extracts of butter was identified by 1D-TOCSY,J-RES,~1H-~1H COSY spectra.The result suggest that this method can not only clarify the target but also non-target components in butter.