Theaflavin (TF) and its derivatives, known collectively as theaflavins, are antioxidant polyphenols that are formed from the condensation of flavan-3-ols in tea leaves during the enzymatic oxidation (fermentation) of black tea. Theaflavin-3-gallate, theaflavin-3'-gallate, theaflavin-3-3'-digallate are the main theaflavins. Theaflavins are types of thearubigins, and are therefore reddish in color. Epigallocatechin gallate (EGCG) will metabolize into some theaflavins in the liver.

Theaflavin (TF) and its derivatives, known collectively as theaflavins, are antioxidant polyphenols that are formed from the condensation of flavan-3-ols in tea leaves during the enzymatic oxidation (fermentation) of black tea. Theaflavin-3-gallate, theaflavin-3'-gallate, theaflavin-3-3'-digallate are the main theaflavins. Theaflavins are types of thearubigins, and are therefore reddish in color. Epigallocatechin gallate (EGCG) will metabolize into some theaflavins in the liver.