什么是茶
茶树(C. sinensis,属茶科)的嫩叶和芽浸泡在开水中制成的饮料。茶树包括40种乔木和灌木。西元350年中国的文献中首先提到茶的栽培;根据传说,大约从西元前2700年後中国已经知道种茶了。13世纪时在日本确立茶业,19世纪时,由荷兰人传播到爪哇,由英国人传播到了印度。如今,茶是世界上消费最广泛的饮料,世界上约有一半人喝茶(热饮或冷饮)。根据加工的方法不同而分成几个大类:发酵茶,或称红茶,生成琥珀色的、不带苦涩的、口味浓郁的饮料;半发酵茶,或称乌龙茶,产生略带苦味的、浅棕-绿色的液体;非发酵茶,或称绿茶,产生温和的、略苦的、浅绿-黄色的饮料。茶的刺激作用来自咖啡因。在远东,长期以来认为绿茶有益於健康,近年来,以它许多可能的有利效应吸引着许多西方爱好者的注意。许多其他不相关的植物的叶、茎皮和根的浸剂和煎剂作为草药或药茶也被普遍地饮用。
tea
Beverage produced by steeping in freshly boiled water the young leaves and leaf buds of the tea plant, Camellia sinensis, a member of the family Theaceae, which contains 40 genera of trees and shrubs. Tea cultivation is first documented in China in AD 350; according to legend, it had been known there since c. 2700 BC. It was established in Japan by the 13th century and was spread to Java by the Dutch and to India by the English in the 19th century. Today tea is the most widely consumed drink in the world, drunk (either hot or cold) by half the world's population. Major tea types are classified by processing method: fermented, or black, tea produces an amber-colored, full-flavored beverage without bitterness; semifermented, or oolong, tea yields a slightly bitter, light brownish-green liquid; and unfermented, or green, tea, results in a mild, slightly bitter, pale greenish-yellow beverage. Caffeine is responsible for tea's stimulating effect. Green tea, long regarded as healthful in the Far East, has in recent years attracted much favorable attention in the West for a wide range of possible beneficial effects. Infusions and decoctions of the leaves, bark, and roots of many other, unrelated plants are commonly drunk as herbal or medicinal teas.
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