基于HS-SPME-GC-MS的茶酒挥发性物质检测方法研究

Study on Detection Method of Volatile Compounds in Tea Liquor Based on HS-SPME-GC-MS

采用50/30μm DVB/CAR/PDMS萃取头,在四种萃取温度(45、50、60、70℃)下萃取40 min,以不分流或分流两种模式,分流模式下包括1∶1、3∶1、5∶1、10∶1四种分流比,分别对茶酒挥发性物质进行萃取,通过气相色谱-质谱检测,建立适用于茶酒挥发性物质萃取分析的检测方法。结果表明,分流模式较适用于茶酒挥发性物质检测,分流比3∶1时检出的茶酒挥发性物质总数最多,且更利于茶酒中低丰度的茶叶挥发性物质检出。萃取温度为50℃时,检测出茶酒挥发性物质总数最多;因此,检测茶酒中挥发性物质的适宜条件为:50/30μm DVB/CAR/PDMS萃取头,萃取温度50℃,萃取时间40 min,分流模式,分流比3∶1。在该条件下,茶酒中共检出70种挥发性物质,其中以己酸乙酯、丁酸乙酯、辛酸乙酯、庚酸乙酯、乙酸乙酯、己酸己酯、戊酸乙酯、己酸等为主,并检出芳樟醇、α-松油醇等茶叶挥发性物质。同时经四大酯、三大酸标准溶液检测验证,该条件具有较好的重复性和准确性,该方法的建立可为茶酒挥发性物质的分析提供参考。

In order to establish a suitable method for extraction and analysis of volatile compounds in tea liquor.The volatile compounds in tea liquor were extracted by using a 50/30μm divinylbenzene/carboxen/polydimethylsiloxane(DVB/CAR/PDMS)extraction head,with 4 extraction temperatures of 45℃,50℃,60℃and 70℃for 40min and detected by gas chromatography-mass spectrometry(GC-MS)using two kinds of split mode,no split mode and split mode,and four different split ratios 1∶1,3∶1,5∶1 and 10∶1 were used in split mode.The results showed that the split injection mode was more suitable for the detection of volatile compounds in tea liquor,and when the split ratio was 3∶1,the total number of volatile compounds in tea liquor was the most,and it was more conducive to the detection of low abundance volatile compounds of tea in tea liquor.When the extraction temperature was 50℃,the total number of volatile compounds in tea liquor was the most.Therefore,the appropriate conditions for extraction and analysis of volatile substances in tea liquor were 50/30μm DVB/CAR/PDMS extraction head,extraction temperature 50℃for 40 min,split injection and split ratio 3∶1.Under this conditions,70 kinds of volatile compounds were detected in tea liquor.The main volatile compounds were ethyl hexanoate,ethyl butyrate,ethyl octanoate,ethyl heptanoate,ethyl acetate,hexyl hexanoate,ethyl valerate,hexanoic acid and other.The volatile components of tea including linalool andα-terpineol were detected.The method was verified by the standard solution of three major acids and four major esters,which showed good repeatability and accuracy.The establishment of this method can provide reference for the detection of volatile compounds in tea liquor.