Thearubigin

Thearubigins are polymeric polyphenols that are formed during the enzymatic oxidation (called fermentation by the tea trade) of tea leaves. Thearubigins are red in colour. Therefore a black (fully oxidized) tea gives a reddish liquor while a green or white tea gives a much clearer one. The colour of a black tea, however, is affected by many other factors as well, such as the amount of theaflavins, another oxidized form of polyphenols.

It has been believed that theaflavins and thearubigins are important contributors of the taste of a black tea, but recent scientific findings have proven otherwiseFact|date=July 2008. More research is still needed to identify the compounds that make up the major components of the taste of a tea. However, it is known that as thearubigins further oxidize if the tea is poorly stored, the taste is adversely affected.

While both the nature and concentration of polyphenols in unoxidized teas, such as green teas or white teas, have significant effects on human healthFact|date=July 2008, some studies have found thearubigins to have some potency due to their antioxidant propertiesFact|date=July 2008.

ee also

* Theaflavin
* Catechin
* Epigallocatechin gallate (EGCG)