不同季节翠玉品种茶叶香气组分的GC-MS分析

采用GC-MS法对广东省春、夏、秋三季的翠玉茶树品种加工成的绿茶、红茶和乌龙茶的香气进行分析研究。结果表明:在不同季节加工的翠玉绿茶中,春茶和夏茶的香气物质种类较多,秋茶较少;春茶和夏茶的香气成分组成比较相似,都是醇类物质相对含量最高,秋茶是吡咯类及其衍生物的相对含量最高;春茶的主导香气成分种类最多且大部分呈花香型,夏茶的主导香气成分以醇类为主(59%),秋茶的主导香气成分种类最少。不同季节翠玉红茶的香气成分组成较为相似,均为醇类物质的相对含量最高,且所占比例较其他茶类高;主导香气成分组成也较相似,都是以橙花醇、反-橙花叔醇及芳樟醇的氧化物为主。不同季节的翠玉乌龙茶的香气组成较有规律,以醇类、吡咯类及其衍生物为主,主导香气成分中,春茶和夏茶的种类较多,秋茶比较单一,特征香气物质是反-橙花叔醇和吲哚。

Aroma-producing Components of Cuiyu Tea Leaves during Different Seasons by GC-MS

The aroma-producing components in Cuiyu green tea (CGT), Cuiyu black tea (CBT), and Cuiyu Oolong tea (COT) prepared from Cuiyu tea leaves (harvested during spring, summer, and autumn from Guangdong Province, China), were studied by using gas chromatography and mass spectrometry (GC-MS). The results revealed that CGT prepared from tea leaf samples collected during spring and summer contained a larger variety of aroma-producing components than those collected during the fall season. The results for individual components in the spring and summer samples for CGT were similar, where alcohols showed the highest relative content, while pyrroles and their derivatives showed the highest relative content in autumn samples. CGT from spring samples showed the largest number of dominant aroma-producing components, most of which were of floral aroma, CGT from summer samples showed that the dominant components comprised of alcohols (>59%), while CGT from autumn samples showed the lowest number of these dominant components. The aroma-producing components of CBT from different seasons were similar; alcohols consistently showed the highest relative content, and the alcohol proportion was also the highest in CBT when compared with other teas. The dominant aroma-producing components of CBT from different seasons were similar and mainly comprised of nerol, trans-nerolidol, and trans-linalool oxide. The aroma-producing components of COT from different seasons showed a distinct pattern, including mainly alcohols, pyrroles and their derivatives. COT from spring and summer samples showed a larger number of dominant aroma-producing components. Similar components were found in COT from autumn samples, where the characteristic components were trans-nerolidol and indole.