Abstract: Specific climate and environmental conditions in different regions are the key factor that affects microbial community structure and metabolism as well as the formation of flavor components in Fu brick tea (FBT). Therefore, this study evaluated the effect of fermentation in three representative producing regions (Shaanxi, Hunan and Zhejiang province) on the quality of FBT produced from the same raw tea materials in the same time. The results indicated that there were significant differences in sensory evaluation. The number of “golden flora” in FBT from Shaanxi and Hunan were higher than that in FBT from Zhejiang, but Hunan and Zhejiang FBT had a slight grassy and astringent taste. The major chemical components revealed that Hunan FBT had the highest contents of polyphenol, ester catechins, total catechins and caffeine, Zhejiang FBT had the highest amounts of free amino acids and theanine, while Shaanxi FBT had the highest content of organic acids. A total of 57 volatile aroma compounds were identified from FBT produced in three regions. Furthermore, terpene alcohol, olefinic aldehydes and ketone could improve the arohid aroma of FBT significantly (P < 0.05). All results indicated that the diversity of microbial communities associated with fermentation and the direction and function of microbial metabolism will be beneficial for the quality of FBT.

Key words: Fu brick tea, fermentation, microbial population, chemical components, aroma components