The Variation Of The Active Component In Pu’er Tea Fermentation Process With Pure Mould

The thesis selects Aspergillus niger, Aspergillus oryzae and Monascus to ferment Pu’er tea. monitor the conversion of active component in the fermentation process, summarize variation regulation and analysis the effect of dominant strains on the active component in Pu’er tea. This is aim to stabilize the high-quality production of Pu’er tea and improve the quality of the tea.The determination means of active component in the inoculated fermentation process was first determined:(1) Selection of the People’s Republic of China National Standards Act (GB/T8313-2008) as determination means of polyphenols content of Pu’er tea in the fermentation process;(2)Definition high performance liquid chromatography (HPLC) as determination the active ingredients in polyphenol of Pu’er tea;(3)Determination of tea pigment content by spectrophotometer;(4) Definition of the enzyme activity of cellulase and glucoamylase and determination of its size by glucose standard curve as a benchmark;(5) Definition of protease enzyme activity and determination of its size by the use of casein standard curve;(6) selection of the People’s Republic of China national standards Act (GB/T8313-2002) as determination means of caffeine content of Pu’er tea in the fermentation process.The results showed that tea polyphenol content decreased by10%,12.5%and13.5%by access to Aspergillus niger, Aspergillus oryzae and Monascus, while both tea pigment and caffeine content increased and the caffeine content increased by2.5%,2.3%and2.8%. In particular, reducing the magnitude of the polyphenol content was the smallest by access to Aspergillus niger. This would be more conducive to the retention of polyphenols in Pu’er tea. The conversion of some part of the polyphenolic substances as tea pigment was benefit to improve the quality of Pu’er tea, also comparing the color becomes reddish-brown by the yellow-green after fermentation and aroma degree of the tea, better able to promote the function and improve tea taste of Pu’er tea.Cellulase, glucoamylase and protease activity increased first and then decreased in the fermentation process of Pu’er tea. On the four day of the fermentation by access to Aspergillus niger, the maximum value of enzymatic activity of cellulase reached72.31U/ml.On the third day of the fermentation by access to Aspergillus oryzae, the maximum value of enzymatic activity of protease reached22.36U/ml.On the third day of the fermentation by access to Monascus, the maximum value of enzymatic activity of glucoamylase reached0.249U/ml.It can be observed that access to Aspergillus niger strains was more conducive to promoting the generation of enzymatic activity of cellulase, to improve the solubility of Pu’er tea;While access to Monascus strains was more benifit to promote the generation of enzymatic activity of glucoamylase,to improve the degree of fresh,aroma and the quality of Pu’er tea;More obviously, the access to Aspergillus oryzae strains was more conducive to promoting the generation of enzymatic activity of protease,to promote more soluble carbohydrate in Pu’er tea. Though determination of the active ingredient in Pu’er tea fermentation process, it can be observed that Aspergillus niger, Aspergillus oryzae and Monascus play significant role in improving the quality of Pu’er tea, tea color,taste body,aroma,the function of the tea and so on. Especially Aspergillus niger, to establish the foundation for new fermentation process of Pu’er tea.