Abstract: In order to understand the changes of quality components and mycotoxins residues in mildewed raw tea with high humidity, the changes in the contents of various quality components and three mycotoxins in raw dark tea during its incubation at a high relative humidity. The results showed that the contents of polyphenols, catechins (mainly EGCG and EGC), and amino acids (mainly theanine) decreased with increasing degree of mildew, while the total content of purine alkaloids remained substantially stable. In contrast, the content of theophylline slightly increased. The contents of ochratoxin A (OTA), deoxynivalenol (DON) and aflatoxin B1 (AFB1) were undetectable in mildewed raw dark tea, implying that mycotoxins did not occur widely in mildewed dark tea, and contaminating molds may be the main cause of mycotoxins residues in raw dark tea.

Key words: raw dark tea, mildew, quality components, mycotoxins