关键词: 普洱熟茶, 多酚, 咖啡因, 色素, 发酵

Abstract: Pu-erh shucha,a traditional beverage in Yunnan Province,China,is popular in East Asia.The key process for the development of characteristic flavors of Pu-erh shucha is “post-fermentation”;however,little is known about the content variation of chemical components during this process.In this work,the content variation of tea polyphenols,caffeine and pigments during the fermentation process of Puerh shucha was monitored by high performance liquid chromatography (HPLC).The HPLC analysis revealed that the concentrations of (-)-epicatechin (EC),(-)-epigallocatechin (EGC),(-)-epicatechin-3-O-gallate (ECG),(-)-epigallocatechin-3-O-gallate (EGCG),theogallin (TG),strictinin (STR) and 1,4,6-tri-O-galloyl-β-D-glucose (1,4,6-tri-G-G) decreased,while the concentrations of gallic acid (GA) and caffeine (CAF) increased during the fermentation process.It was inferred that gallate catechins hydrolyze to GA during the fermentation process.In addition,the fact that no black tea pigments were detected in the fermenting samples of pu-erh shucha suggested that different pigments existed in the different teas.

Key words: Pu-erh shucha, polyphenols, caffeine, pigment, fermentation