从茶叶中提取咖啡碱的研究

目的]探讨从茶叶中提取咖啡碱的方法。方法]以陕西汉中产的4个品种茶叶为试材,用Soxhlet提取法从茶叶中提取咖啡碱,并用红外光谱仪对咖啡碱的结构进行表征,研究茶叶的品种对咖啡碱收率的影响。结果]茶叶品种对咖啡碱的收率影响较大,低档茶大叶青茶的咖啡碱收率(1.32%)比高档茶特级汉水银梭的收率(0.51%)高得多。不同茶叶具有不同的咖啡碱含量,低档茶中的咖啡碱的含量比高档茶的高。汉中茶口感清纯,主要是由于其中咖啡碱的含量低于普通的茶叶。结论]采用Soxhlet提取法可有效地从茶叶中提取咖啡碱,其操作工艺简单易行。

Study on Extraetion of Theine from Tea

Objective]The purpose was to discuss the method of extracting theine from tea.Method]With 4 tea varieties produced in Hanzhong of Shaanxi as tested materials,the theine was extracted from tea by Soxhlet extraction and the structure of theine was characterized by infrared spectrometer to study the influence of tea variety on theine yield.Result]The tea variety had bigger influence on theine yield.The theine yield from the low-grade tea Dayeqing(1.32%) was much higher than that from the high-grade tea special-grade Hanshuiyinsuo(0.51%).Different teas had different theine contents and the theine content in low-grade tea was higher than that in high-grade tea.Hanzhong tea tasted fresh and pure,it was mainly because its theine con-tent was lower than that in common tea.Conclusion]The theine could be extracted from tea effectively by Soxhlet extraction and the operation technology was simple and feasible.