自动化静态顶空-气相色谱-质谱对天然香精中挥发性化学成分的快速分析

Fast Analysis of Volatile Compounds in Natural Essences by Automatic Static-Headspace-GC-MS

运用静态顶空 -毛细管气相色谱 -质谱法对天然香精中挥发性化学成分进行了分析 ,采用质谱和保留指数检索结合的方法对香精中挥发性成分进行定性分析 ;对香精顶空分析条件进行了优化 ,在香精样品中加入适量饱和NaCl溶液 ,显著地提高了低极性挥发性组分的分析灵敏度 ;从该香精中检出了68个化合物 ,将峰面积归一化结果大于0.1 %的60种挥发性成分进行了定性分析 ,并通过保留指数分析对其中45种化合物进行了确认 ;分析结果表明 :香精中含有萜类 (30.3 % )、萜类衍生物 (11.7 % )、酚醚类 (17.0 % )、脂肪酸酯(20.9 % )和一些小分子的缩醛类化合物 (17.7% ) ,其中主要的挥发性成分为丁酸_1,1_二甲基_苯基乙酯(18.9 % )、茴香脑 (15.6% )、2_乙基_4_甲基_1,3_二氧戊环 (9.8 % )和 β_石竹烯 (7.7 % ) ;对方法精密度进行考察 ,相对标准偏差 (RSD)在0.62～9.36之间。

A fast method for the analysis of volatile compounds in natural essence by automatic static-headspace-GC-MS was established.The qualitative analysis of volatile compounds in essence was perˉformed by using mass spectrum and retention index library search.The analytical sensitivities of lowpolar volatile compounds in essence increased greatly in the presence of an appropriate amount of saturated NaCl solution.The operating conditions for static-headspace-GC-MS were optimized.Sixty-eight comˉpounds in the essence were identified.Sixty volatile compounds with normalized peak area larger than0.1%were analysed qualitatively.Among them,45compounds were finally confirmed with retention inˉdices.It was found that the main compounds of this essence were butanoic acid1,1-dimethyl-phenylethyl ester(18.9%),anethole(15.6%),2-ethyl-4-methyl-1,3-dioxolane(9.8%)and beta-caryophyllene(7.7%),respectively.The RSD of this method was0.62%～9.36%.The establised method is suitable for the quality control of essence.