Green teas are often referred to as non-fermented or unfermented teas. The chief feature in manufacturing of green tea as distinguished from black is that the leaves do not undergo any process of fermentation, while the slow operation of natural withering is replaced by a more rapid one for steaming or sun drying. The objective of this is to inactivate the enzyme and thereby preventing the process of fermentation. The traditional method of processing green teas involves withering (though not always), heating, rolling and drying. After plucking, the fresh leaves are spread out on bamboo trays and exposed to sunlight or warm air for one to two hours. Then the leaves are heated to prevent oxidation and preserve freshness. Finally, the leaves are rolled into various shapes and then dried. The rolling also helps regulate the release of natural oils and flavor during steeping.
