Abstract: Microbial extracellular enzyme catalytic activity is the key factor of dark tea quality formation, and the later storage causes changes in the microbiological system in dark tea. To explore the potential food safety risks of fungus system in dark tea products, the research results of dark tea fungi pollution were reviewed. It showed that a variety of contaminating fungal toxins could be detected in dark tea samples, such as aflatoxins, ochratoxins, deoxynivalenol. Studies showed that toxin exposure of dark tea samples were low, and multi-active components of dark tea could down-regulate part of genes associating with aflatoxins, thus inhibited aflatoxin production in dark tea matrix samples. It was pointed out that it is safe to produce and drink dark tea regularly, and the development direction of dark tea processing is the application of directional fermentation technologies.

Key words: dark tea, fungi, mycotoxins