顶空-固相微萃取/气相色谱-质谱联用法分析“无锡毫茶”中的香气成分

Analysis of Volatile Components of Wuxi Baikhovi Tea by HS- SPME /GC- MS

建立了顶空-固相微萃取/气相色谱-质谱联用(HS-SPME/GC-MS)分析"无锡毫茶"香气的方法,并考察了固相微萃取头种类、萃取温度、预热时间、吸附时间、茶叶颗粒度、茶样量对HS-SPME吸附"无锡毫茶"香气物质种类和总量的影响。结果表明:采用过70目筛的茶样2.0 g在80℃下预热5 min后,插入碳分子筛/二乙烯基苯/聚二甲基硅氧烷(CAR/DVB/PDMS)固相微萃取头吸附40 min,能达到最佳吸附效果;将吸附的香气物质在GC-MS进样口内经250℃解吸3 min,共鉴定出53种"无锡毫茶"香气成分,其中以叶醇及其酯、芳樟醇及其氧化物、苯乙醇、香叶醇、橙花叔醇、金合欢烯、顺-茉莉酮、紫罗兰酮、吲哚、二甲硫醚等为主共同赋予了无锡毫茶清香而带有花果香的香气特征。

Head space solid-phase micro-extraction（ HS-SPME）coupled with gas chromatography-mass spectrometric（ GC-MS）method was developed for the analysis of Wuxi baikhovi tea. Effects of SPME fiber type,extraction temperature,preheating time,adsorption time,particle size of tea and mass of tea on kinds and amounts of aroma compounds in baikhovi tea were studied. The optimum conditions were as follows：2. 0 g Wuxi baikhovi tea was used in 70 mesh,SPME fiber：carboxen （ CAR）/divinylbenzene（ DVB）/polydimethylsiloxane（ PDMS）fiber,extraction temperature：80 ℃, preheating time：5 min,adsorption time：40 min. After the extraction,the fiber was inserted into the injector port of GC-MS system and the extract was desorbed at 250℃ for 3 min. Total of 53 vol-atile compounds were identified in Wuxi baikhovi tea. Among them,cis-3-hexen-1-ol and its esters, linalool and its oxides, phenethyl alcohol, geraniol, nerolidol, farnesene, cis-jasmone, ionone, indole and dimethyl sulfide are more important to the total green,floral and fruity aroma of Wuxi baikhovi tea.