基于化学成分的古树普洱茶原料产地鉴别研究

目的基于化学成分鉴别古树普洱茶原料的产地。方法测定不同产地不同季节古树普洱茶原料中主要化学成分,并对数据进行差异性分析、主成分分析、Fisher判别分析。结果春季古树普洱茶原料的水浸出物、茶多酚含量较高,秋季古树普洱茶原料的粗纤维、游离氨基酸总量、可溶性糖、儿茶素总量较高;不同产地古树普洱茶原料在茶多酚、儿茶素(catechin,C)、表儿茶素(epicatechin,EC)、表没食子儿茶素(epigalloeateehin, EGC)、表儿茶素没食子酸酷(epieateehingallate, ECG)存在显著差异;运用主成分分析可以很好地区分不同季节的古树普洱茶原料,但是不能很好区分不同产地的古树普洱茶原料;采用Fisher判别分析方法可以较好地区分不同产地的普洱茶原料,总判别正确率为90%。结论茶叶中的化学成分可以用于区分不同季节不同产地的古树普洱茶原料。

Study on the identification of the origin of ancient Pu'er tea raw materials based on chemical composition

Objective To identify the origin of ancient Pu''er tea raw materials based on chemical composition. Methods The main chemical components in ancient Pu''er tea raw materials from different origins and seasons were determined, and the datas were analyzed by difference analysis, principal component analysis and Fisher discriminant analysis. Results In spring, the water extract and tea polyphenol content of ancient tree Pu''er tea raw materials was relatively high, while in autumn, the crude fiber, total free amino acid, total soluble sugar and catechin content of ancient tree Pu''er tea raw materials was relatively high. There were significant differences in tea polyphenols, catechin (C), epicatechin (EC), epigalloeateehin (EGC) and epieateehingallate (ECG) among ancient tree Pu''er tea raw materials from different producing areas. Principal component analysis could be used to distinguish the raw materials of ancient tree Pu''er tea in different seasons, but it cannot distinguish the raw materials of ancient tree Pu''er tea in different producing areas. Fisher discriminant analysis method could be used to distinguish Pu''er tea raw materials from different producing areas, and the total discriminant accuracy rate was 90%. Conclusion The chemical components in tea can be used to distinguish the ancient Pu''er tea raw materials from different seasons and different producing areas.