Fermented tea

Tea that has undergone microbial fermentation

Fermented tea (also known as post-fermented tea, and literally translated as black tea from Chinese) is a class of tea that has undergone microbial fermentation, from several months to many years. The exposure of the tea leaves to humidity and oxygen during the process also causes endo-oxidation (derived from the tea-leaf enzymes themselves) and exo-oxidation (which is microbially catalysed). The tea leaves and the liquor made from them become darker with oxidation.

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