Abstract: It has been known that microbial species and quantity have a great influence on the quality of Pu-erh tea during its storage. In this study, four types of selective media were used to culture microorganisms in a 10-year-old fermented Pu-erh tea. The colonies of microorganisms than can grow in each medium were counted. Then, microbial isolation and morphological identification under a microscope were performed. 16S rRNA sequence analysis was used for further identification. The results showed that the total bacterial count in the 10-year-old fermented Puer tea was approximately 4.3 × 103 CFU/g and the mold count was roughly20 CFU/g. Neither yeast nor actinomycete was observed. Seven bacterial strains were isolated and identified as gram-positive bacteria belonging to five species, namely Bacillus subtilis (2 strains), B. amyloliquefaciens (1 strain), B. licheniformis (2 strains), B. sporothermodurans (1 strain) and B. shackletonii (1 strain). Only two mold species such as Aspergillus niger and Penicillium chrysogenum were isolated and identified through microscopic observations.

Key words: aged fermented Pu-erh tea, bacteria, molds, identification