Abstract: Different raw tea materials made by 3 tea plant cultivars (BaiyeDancong, Jinxuan and Jiukeng) with different fermentation degrees were adopted to process tea beverages in the research. The quality stability of the tea drinks were studied by analyzing the physical and chemical components and the evaluation of organoleptic quality. Effects of raw tea’s fermentation degree and biochemical substrates on tea cream stability of tea drink were also carried out. The results showed that: Because of different biochemical substrates, the effect of tea beverages processed by different tea varieties is obviously different for Transparency, Jinxuan was better than Jiukeng, and Baiyedancong was worst. There is no clear boundary between tea beverage and the floc settling. Tea cream increased significantly and it become darker in color as the severity of fermentation. Delamination of brown cream and white cream can be found in Jinxuan tea beverage. Of the same species, with the increasing degree of fermentation, content of tea cream first increased and then decreased. Contents of tea cream in raw tea made by production process of black tea which is fully fermented is relatively small amount, indicated that black tea was more suitable for the production of tea drinks. TP concentration in tea cream averaged 36.47%, which indicated that tea polyphenol is one of the main control factors in cream formation. With the extent of tea fermentation, TP concentration in tea cream increased and then decreased; also the same trend with the content of EGC. Therefore, EGC may be the main factor determining the cream formation volume.

Key words: fermentation degree, biochemical substrates, tea drink, tea cream