不同茶树品种紫色芽叶茶叶中多酚类与咖啡碱含量比较分析

Analysis of the Content of Polyphenols and Caffeine in Different Purple Bud Tea Varieties

采摘乌牛早、南山白毛及紫娟等3个茶树品种的紫色芽叶为原料,分别直接烘干及加工成绿茶、红茶和白茶,采用紫外分光光度计法和高效液相色谱法分别检测分析茶叶中的多酚类与咖啡碱含量差异。结果显示,不同茶树品种的紫色芽叶及其加工的茶类产品中多酚类与咖啡碱含量不同。南山白毛绿茶(NL)儿茶素与表没食子儿茶素没食子酸酯(Epigallocatechin gallate,EGCG)相对含量均比其他茶样高,分别为14.33%和10.11%。同一茶树品种芽叶加工的绿茶中茶多酚、花色苷及儿茶素类总量均比加工的红茶和白茶高,加工的白茶中咖啡碱的含量相对较高;3个品种茶树芽叶加工同一茶类茶叶中,花色苷含量均表现为:乌牛早<南山白毛<紫娟,南山白毛芽叶加工的茶叶中茶多酚与EGCG含量相对较高,乌牛早的茶叶中咖啡碱含量较低。在广西区域内,南山白毛与乌牛早也可作为富含花青素的紫芽茶树资源加以开发利用。

The purple buds leaves of three tea varieties,Wuniuzao,Nanshan Baimao and Zijuan,were used as raw materials to prepare direct drying tea,green tea,black tea and white tea,respectively.The content differences of polyphenols and caffeine were detected by ultraviolet spectrophotometry and high performance liquid chromatography.The results show that,the contents of polyphenols and caffeine in tea products from different varieties and different processing techniques are different.The relative contents of catechins and epigallocatechin gallate (EGCG) in Nanshan Baimao green tea (NL) were higher than those of other tea samples,which were 14.33% and 10.11% respectively.In the same variety and different processing techniques,the total content of tea polyphenols,anthocyanins and catechins in green tea are the highest,while the content of caffeine in white tea is relatively high;With the same processing technology,the content of anthocyanins in Wuniuzao,Nanshan Baimao and Zijuan teas of different varieties of tea plants increased successively,the contents of polyphenols and EGCG in Nanshan Baimao tea were relatively high,and the contents of caffeine in Wuniuzao tea were relatively low.In summary,the two tea plants,Nanshan Baimao and Wuniuzao,can be developed and utilized as purple bud tea variety resources rich in anthocyanins.