Advances in formation and oxidation mechanism of theaflavins during black tea fermentation

  • AN Jiale ,
  • DING Yangping
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  • (College of Food Science, Southwest University, Chongqing 400715, China)

Received date: 2025-09-22

  Revised date: 2025-12-18

  Online published: 2026-07-31

Abstract

Theaflavins are key components responsible for the quality and health benefits of black tea.However, the mechanisms underlying their formation and oxidation during the fermentation process remain incompletely understood.A systematic review of recent research advances in this field is presented.First, regarding the formation mechanism, various controversies and consensus concerning multiple biosynthetic pathways of theaflavins are summarized and compared, with the critical role of the bicyclo[3.2.1]octane intermediate clarified.Second, in terms of the oxidation mechanism, the key intermediate theanaphthoquinone and its transformation pathways, which have attracted significant attention in recent years, are comprehensively reviewed, and multiple branching routes leading to thearubigins and theabrownins are elucidated.Finally, regarding research methodologies, various approaches, such as enzymatic oxidation, chemical oxidation, and computational chemistry are emphasized, with the unique advantages of computational chemistry in analyzing unstable reaction intermediates and pathways highlighted.This review provides a theoretical foundation for the precise regulation of black tea fermentation and for the development of theaflavin-based functional products.

Cite this article

AN Jiale , DING Yangping . Advances in formation and oxidation mechanism of theaflavins during black tea fermentation[J]. Food and Fermentation Industries, 2026 , 52(13) : 441 -453 . DOI: 10.13995/j.cnki.11-1802/ts.044616

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