Green Teas are the main teas produced and drunk in China and Japan. Oxidation of the fresh leaves results from dehydrating the leaves by "firing" or steaming then drying them, so conserving their green hue and fresh characteristics. Other regions grow green teas nowadays, with those from India being especially clean-tasting and delicious.
Well-known Green Teas
70% of Chinese teas are green teas, grown mainly in southern China in Anhui, Fujian, Henan, Jiangsu, Jiangxi and Zhejiang Provinces. Green teas from China are picked, rolled and then immediately dried in hot-air dryers or giant woks before they start to oxidise and turn brown. Healthy and full of antioxidants. In the past, green teas were called Hyson, with the higher quality ones called "Young Hyson".
Green teas from Japan were learnt from the Chinese styles. While famous for its tea ceremony, Japan has a wide range of good quality teas.
Processing Green Teas
China: Making Green Teas
- Picking: usually the leaves are picked when young (bud plus one or two leaves). There are exceptions - Lu An Gua Pian uses only leaves and no bud; Tai Ping Hou Kui used more mature leaves.
- Withering: traditionally the green leaves are spread on bamboo racks and left to dry for 1 - 3 hours to remove surplus water; to prevent them drying out too much, they may be spread on cloths in the shade. Modern methods use mechanical driers - the leaves are placed in a cylindrical drum with bamboo walls, so they dry for a few minutes while fans blow air through them. Withering starts the process of dehydration that stops oxidation of the green tea caused by oxidase, an enzyme that reacts with oxygen in the air.
- Heating: dehydration continues with heating the leaves until the enzymes that drive oxidation are denatured. While methods vary across China, it generally involves small amounts of withered leaves being put into pans or vats and heated with wood, coal or electricity. The leaves are pressed to the bottom of the vat and they constantly stirred to ensure they don't burn. The next stage depends on the final shape for the leaves: Long jing-style flat leaves are pressed to the bottom of the vat before being stirred in a back-and-forth action; for gunpowder-style curly leaves, the leaves are rolled by hand and constantly stirred until they are dry. Generally, the heat starts warm then is heated up further as the process continues. In mechanical heating, they are heated at least 3 times in rotating cylinders and rolled between heating. In both traditional and mechanical methods, sugars and proteins are transformed to give a slight nutty taste, and polyphenols are released in the leaves that give green tea its health properties.
- Rolling: the green leaves have their cells broken to release the aromatic oils within. Rolling changes the shape of the finished product and provides some of the characteristic flavours of Chinese green teas. Processing is either by hand or using various machines to give flat or curly leaves.
- Drying: the remaining water is removed to prevent mould and aromatic oils from the rolling stage are stabilized. At the end, only 2 - 4% of moisture remains in the leaves.
- Sifting: the leaves are sieved to remove any broken leaves from the processing stages. The green tea leaves are sorted into sizes using bamboo meshes of different sizes.