Characteristics of bacterial community during the pile fermentation of Pu-erh tea in a five-ton batch of Pu-erh tea commercial production process

Abstract

The purpose of this investigation was to study the bacterial community and the dominant bacterial species in the fermentation process of Pu-erh tea. Bacteria were isolated under different temperature, humidity and acidity conditions according to the actual pile-fermentation characteristics. The 16S rRNA gene analysis results revealed that these bacteria could be classified as 27 species. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) profile showed that Klebsiella pneumoniae, Enterobacter turicensis, Lactobacillus plantarum, and Enterobacter aerogenes presented as dominant species. The number of these four dominant bacteria reached 108, 108, 105 and 107 copies/g dry tea, respectively, at the initial stage detected by real-time quantitative PCR (q-PCR), and all decreased during the process of pile fermentation. The knowledge will enable industrial selection, maintenance and growth of starter culture for high quality Pu-erh tea.