The chemistry of tea manufacture (original) (raw)
NASA/ADS
Abstract
Many of the substances occurring in freshly plucked tea shoots are listed and the chemical changes taking place during withering and fermentation are discussed. In fermentation (—)-epigallocatechin and its gallate are the only polyphenols to undergo appreciable chemical change. A scheme for the oxidation of these substances is developed which suggests that substances A, B and C are bisflavanols, and that theaflavin and theaflavin gallate are derivatives of purpurogallin. Thearubigins are probably formed as a result of coupled oxidation of theaflavins. Structures are also suggested for the minor components P, Q, R and Z. It is probable that theaflavins and thearubigins account for the colour and strength of tea liquors, and that theaflavins also contribute towards quality and briskness.
Publication:
Journal of the Science of Food and Agriculture
Pub Date:
July 1958
DOI:
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