Microbial distribution and contamination in black tea

Surprisingly, most of the tea samples were contaminated with various microorganisms like E. coli, Salmonella sp., molds etc. Tea samples were received from tea estates of Upper Assam, South Bank and North Bank regions predominantly in peak growing season (summer) and in back end crop (winter season).

The standard plate count (SPC) technique was followed to assess the microbial load such as total plate count (TPC), yeast and mold populations and intestinal enterobacteria like Escherichia coli and Salmonella sp. Intestinal microorganism, E. coli and Salmonella sp. were not detected in any of the tea samples of the three regions till 2015 whereas mold population and other microbes were abundant on total plate count. Contamination of E. coli and Salmonella sp. was detected along with other microorganisms in the tea samples analysed during 2016 and 2017.