Effect of exogenous enzymes on the quality of Pu 'er crude tea extract

Studying on the influence of the type and dose of laccase,protease and tannase enzyme,which were added to Pu'er tea extract,on extract intrinsic component content. The single factor experimental results demonstrate that exogenous enzymes could significantly adjust Pu'er tea extract intrinsic component ratio and improve the quality of tea. To theabrownin prime targets for the main study,orthogonal experiment results showed that three enzymes contribution to theabrownin formation from big to small order for laccase,protease,tannin enzyme. The optimal proportion for three kinds of enzymes were 0.15%,0.05%,0.03%. The result showed that tea polyphenol contained 28.71% which was decreased 8.45% comparing with that before the treatment.The concentration of soluble sugar,amino acid acquire,theabrownin to 11.97%,3.58%,8.60% respectively under the conditions,which were 3.49,1.10,4.32 times than that before the process of enzyme treatment. This process revised the composition ratio of Pu'er crude tea extract and oxidates theabrownin rapidly in a short term,these transform significantly improved the quality of tea ranging from pure and mellow taste to glow color.It would promote the liquid process,that using enzyme to ameliorate the quality of tea.