Variations of Main Biochemical Components and Their Relations to Quality Formation during Pile-fermentation Process of Yunnan Puer Tea
Luo Longxin; Wu Xiaochong; Deng Yuliang; Fu Shangwen(Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008)
Variations on the contents of main components were investigated during pile-fermentation processing of Yunnan Puer tea. The results showed that the components were sharply increased or decreased with the time of pile-fermentation. Up to the end of pile-fermentation, the contents of tea polyphenols, catechins, TF, TR,amino acids, and soluble sugar were greatly decreased, while the contents of TB and insoluble polyphenols were obviously increased. However, the total content of water extracted substances was slightly changed and it indicated that some new substances formed from the oxidation, degradation, and condensation of the com-ponents, which gave the color, taste and aroma to Puer tea. Apart from the effects of moisture and tempera-ture under special conditions, the growth and metabolism of microbe played an important role in the great variations of the components. The quaIity formation of Puer tea was also discussed in the paper.