The Study On Improving The Quality Of Green Pu'er Tea

The quality and content of main chemical components in green Pu'er tea treated by different storage condition, enzyme and ozone were analyzed in the aging process. The techniques on improving the quality of green Pu'er tea were discussed.The quality and content of main chemical components in green pu'er tea under different storage temperature, water content and storage time have been studied during 12 day-long storage process. Results indicated that the effect of storage condition on green Pu'er tea was significant in storage process. With the increasing of storage temperature and water content, the content of tea polyphenols and catechins decreased. As a result, theabrownin increased. Theaflavins and thearubigins showed a humping like and a wave type.The quality and content of main chemical components in green pu'er tea under treatment of POD, PPO, and flavourzyme have been studied. Results indicated that the content of tea polyphenols and catechins decreased, the content of theaflavins, theabrownin and theine increased, the content of thearubigins had a fluctuating trend under the treatment of different enzyme. The content of theaflavins increased from 2.3 to 8.3 times, theabrownin increased from 1.4 to 2.5 times, and theine increased from 7.1 to 64.28 percent in green Pu'er tea under the treatment of POD. The content of theaflavins increased from 1.2 to 2.9 times, theabrownin increased from 1.2 to 1.9 times, and theine increased from 17.85 percent to 1.3 times in green Pu'er tea under the treatment of PPO. The content of theaflavins increased from 63.51 percent to 10.7 times, theabrownin increased from 2.9 to 3.8 times, and theine increased from 1 to 25 percent in green Pu'er tea under the treatment of flavourzyme.The quality and content of main chemical components in green pu'er tea under treatment of different ozone have been studied. Results indicated that the content of tea polyphenols ,catechins and thearubigins decreased, the content of theaflavins increased from 4.06 to 65.57 percent, theabrownin increased from 1.1 to 2.9 times, and theine increased from 23.81 to 44.05 percent in green Pu'er tea under the treatment of ozone in acidic condition. The content of tea polyphenols, catechins decreased, the content of theaflavins increased from 14.86 to 72.97 percent, theabrownin increased from 2.6 to 3.5 times, the content of thearubigins and theine had a fluctuating trend in green Pu'er tea under the treatment of ozone in alkaline condition.The headspace solid-phase micro extraction (HS-SPME) coupled with capillary gas chromatography-mass spectrometry (GC-MS) was used for the determination of volatiles in Pu'er tea. The amount of terpenols compounds reduced significantly in the tea sample under the treatment of POD and flavourzyme; the amount of linalool oxide and epoxylinalol were increased in the tea sample under the treatment of PPO; the amount of terpenols compounds reduced significantly in the tea sample under the treatment of high temperatureand high water content and ozone in the alkaline condition; the content of linalool, linalool oide and epoxylinalo were increased significantly in the tea sample under the treatment of ozone in the acidic condition...