普洱茶粉挥发性成分全二维气相色谱/飞行时间质谱研究

以非极性柱Rxi-5Sil MS为第一维柱,中等极性柱Rtx-200为第二维柱,对普洱茶粉的挥发性成分进行全二维气相色谱-飞行时间质谱分析。结合飞行时间质谱普检索图库与全二维特有结构信息谱图,鉴定出相似度大于800、含量≥0.1%的物质90种,占总峰面积的66.306%。研究结果表明,全二维气相色谱-飞行时间质谱联用系统的高分离度、高峰容量和高灵敏度,以及全二维分离特有的结构谱图特征,非常适合于普洱茶粉中复杂挥发性组分的研究。

Analysis of Volatile components in Instant Pu-erh Tea by Comprehensive Two-Dimensional Gas Chromatography/Time-of-Flight Mass Spectrometry

A method was established to determine volatile components in instant pu-erh tea using comprehensive two-dimensional gas chromatography (GC×GC) coupled with time-of-flight mass spectrometry (TOFMS). A non-polar column Rxi-5SilMS(30 m×0.25 mm×0.25 μm)and a middle-polar column Rtx-200 (2 m×0.15 mm×0.15 μm) were used as ifrst and second dimensional columns, respectively. By TOFMS spectral library searching and comparison with unique comprehensive two-dimensional proifles with structural information, 90 volatile components (relative content≥0.1%) with similarity of more than 800 were identiifed in this study, accounted for 66.306% of the total peak area. The results showed that GC×GC-TOFMS method is suitable for separation and identiifcation of the complex volatile compounds in instant pu-erh tea.