The phenolic substances of manufactured tea. II. — Their origin as enzymic oxidation products in fermentation

Abstract The brown acidic pigments and the yellow neutral pigments of black tea are provisionally named thearubigins and theaflavins respectively. These and other substances characteristic of black tea are formed during the fermentation process, mainly as the result of the enzymic oxidation of (—)‐epigallocatechin and (—)‐epigallocatechin gallate. It is probable that the theaflavins are intermediates in thearubigin formation.