Theaflavins
Definition
A family of orange-red pigments formed during the oxidation of catechins in black tea production. Theaflavins contribute briskness, brightness, and a significant share of black tea's color.
Why it matters
Theaflavins are formed when paired catechins, specifically epigallocatechin gallate (EGCG) and related compounds, are oxidized and coupled by polyphenol oxidase during black tea processing. Structurally they form characteristic benzotropolone rings that absorb light in the orange-red part of the spectrum. In black tea liquor, theaflavins are responsible for much of the bright orange-red color near the rim of the cup and contribute to the brisk, lively mouthfeel associated with quality black teas. Theaflavin content is generally higher in well-made orthodox teas with carefully managed oxidation; over-oxidation tends to convert theaflavins into the larger, browner thearubigins. Research on theaflavins has explored possible cardiovascular and metabolic effects, although strong clinical conclusions require further study. In practical tea tasting, the term most often appears in discussions of black tea quality and color.