Nurturing life through tea, nature and architecture
UNDERSTANDING TEA · THEABROWNINS

The reddish-brown colour in your cup

A cup of ripe tea may have a reddish-brown colour. Theabrownins are a group of pigments that contribute to that colour. Researchers are studying their composition and how they form. The colour alone cannot tell us how much theabrownin a tea contains.

Where they come from

Catechins are among the compounds that contribute to tea’s astringency. During processing and storage, tea compounds can undergo oxidation and react with one another. Microorganisms and enzymes take part in the changes during pile fermentation.

Research describes several pathways by which theabrownins may form, rather than a single fixed sequence through theaflavins and then thearubigins. Aroma, flavour and colour also change as tea is made and stored, but those sensory impressions cannot tell us its theabrownin content.

What is known, and what is not

Research commonly describes theabrownins as a group of water-soluble brown pigments. They are a complex mixture, not a single substance with a fully established structure.

Their composition and measured content depend on the tea sample and the analytical method. A figure reported in one study should therefore not be treated as the expected content of other teas. THEN has not published batch-specific theabrownin measurements.

What this means for THEN’s tea

We have not published theabrownin measurements for individual batches. A reddish-brown brew cannot tell us how much a tea contains; laboratory analysis is needed. When results are available, we will publish them here with the laboratory reports.

Tea is food, not medicine. THEN does not claim that tea treats disease.

FURTHER READING

Research from around the world

Article titles are kept in English as published. Select a title to open the original paper.

Reviews

These three papers review the current state of knowledge. They are a useful place to begin.

How theabrownins form during fermentation

On pile fermentation, microorganisms and the changes in tea’s colour and flavour.

The structure of theabrownins

A part of the science that is still being explored.

Theabrownins in living systems

The papers below include experimental research, research on tea consumption in people, and a discussion of how to interpret laboratory findings. Each needs to be read in the context of what was studied and how. Findings about a particular tea, group of compounds or experimental model do not automatically apply to other products. THEN keeps the original titles so you can read and assess the papers for yourself. We do not use them to claim health benefits for THEN’s teas.