Glossary · Processing

Oxidation

The enzymatic browning reaction that occurs when tea leaf cells are broken and exposed to oxygen — the same process that turns a cut apple brown. Oxidation level is the primary thing separating tea categories from one another.

Worth knowing

Frequently mislabeled as 'fermentation' on packaging, but true microbial fermentation only happens in pu-erh and other dark teas.

Related terms

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