What is Fermented Tea?

Fermented Tea is a biochemical process by which enzymes found in yeast cells convert sugar molecules into almost equal parts of alcohol and carbonic gas. Obviously, therefore, fermentation is not involved in tea manufacture, since no alcohol results. The term is nevertheless widely used of tea manufacture to mean oxidation. And oxidation is also called "fermentation," stage following rolling in black tea manufacture, when the leaf is left to oxidize. The time required for oxidation varies widely depending on the nature of the leaf, the rolling method used, the temperature of the leaf and the ambient atmospheres warmth and humidity. Various chemical changes that take place during oxidation are responsible for the briskness, strength and colour of the resulting tea. The aroma of the leaf develops markedly as oxidation proceeds.