基于两步顶空进样-GC-MS法分析不同类型烟叶的挥发性成分

为考察不同类型烟叶挥发性成分的差异，采用两步顶空进样-GC-MS法分析烤烟、雪茄烟、白肋烟、香料烟和晒黄烟烟叶的挥发性成分。两步顶空进样是将静态顶空进样器与程序升温进样口耦合，采用大体积的顶空进样环提高灵敏度，同时采用程序升温进样口以避免因进样体积较大引起的色谱峰展宽。结果表明：(1)采用新方法共从5种类型烟叶中检出121种挥发性成分；(2)采用主成分分析和系统聚类分析验证了挥发性成分组成与烟叶类型的关系；(3)晒黄烟与香料烟的挥发性成分组成最为相似，雪茄烟挥发性成分组成明显区别于其他类型烟叶；(4)雪茄烟挥发性成分组成与产地有关。该分析方法简便、灵敏、可靠，可用于烟叶成分研究及品质评价。

Analyzing volatile compounds in different types of tobacco utilizing a two-step headspace-gas chromatography-mass spectrometry method

In order to illustrate the differences in volatile components of various types of tobacco, a newly developed two-step headspace sampling-gas chromatography-mass spectrometry method was applied to analyze flue-cured tobacco, cigar tobacco, burley, oriental and sun-cured tobacco. The two-step headspace sampling system involved a coupling of the headspace sampler and a programmed temperature vaporizer, which adopted a purposely made large-volume loop to increase the method sensitivity, and then a programmed temperature vaporizer to avoid the peak broadening caused by the large injection volume. The results showed that: 1)a total of 121 volatile components were detected from the five types of tobacco; 2)the principal component analysis and hierarchical cluster analysis were performed to verify the relationship between the volatile compositions and the tobacco type; 3)the volatile components of sun-cured and oriental tobacco was the most similar, while the cigar tobacco was different from all the other types of tobacco; 4)the composition of volatile components of the cigar tobacco was closely related to its leaf origins. In conclusion, the new method is simple, sensitive and reliable, and could be used to evaluate tobacco components and tobacco quality.