HS-GC/MS法分析乌龙茶挥发性成分

本试验旨在采用静态顶空-气相色谱/质谱法(HS-GC/MS)建立起一种快速测定分析以金观音为代表的乌龙茶中挥发物的方法。本方法利用单因素试验结合L9(34)正交试验,以出峰个数和总峰面积为考察指标,确定了顶空平衡温度、平衡时间、茶/Na Cl以及加样量4种因素的最佳萃取条件,并以此方法对金观音的挥发性成分进行了分析。结果表明,平衡温度对出峰个数和总峰面积的影响最大,而平衡时间的影响最小。试验得出的顶空进样的最优条件为:平衡温度80℃,平衡时间60 min,茶/Na Cl为1∶2,加样量为0. 5 g。在此萃取条件下能够得到104种物质,这些物质能更真实地反映金观音香气成分的化学构成,为以金观音为代表的乌龙茶的开发利用提供有价值的数据。

Analysis of volatile components in Oolong tea by HS-GC/MS

The purpose of this experiment is to establish a rapid method for the determination and analysis of volatiles in Oolong tea represented by Jin Guanyin by static headspace gas chromatography/mass spectrometry(HS-GC/MS).Using L 9(3 4)orthogonal test combined with single factor test and taking the peak number and peak area as indexes,we obtained the optimum extraction conditions of 4 kinds of factors,include headspace equilibrium temperature、equilibrium time、tea/NaCl and sample dosage.In the end,the volatile components of Jin Guan Yin were analyzed by this method.The results showed that the equilibrium temperature had the greatest influence on the number of peaks and the total peak area,while the equilibrium time had the least influence.The optimum conditions of headspace sampling were as follows:equilibrium temperature was 80℃,equilibrium time was 60 min,tea/NaCl was 1∶2,and the sample dosage was 0.5 g.We gained 104 kind of components in the extraction conditions,which can better reflect the chemical composition of Jin Guan Yin’s aroma and provide valuable data for the development and utilization of Oolong tea represented by Jin Guan Yin.