Tea is a beverage, the turnout processed leaves, flowers or branches of the tea bush Camellia sinensis in hot water for a few minutes. The processing can oxidation, heating, drying, and the addition of other herbs, flowers, fruits and spices. The four basic types of tea are true (in order from most to least-processed): black tea, oolong tea, green tea and white tea. The term "herbal tea" in the rule refers to infusions of fruit or herbs (such as rosehip, chamomile, or jiaogulan), which no Camellia sinensis. (Alternative words for herbal tea avoid the word "tea" are tisane and herbal tea.) This article deals exclusively with the preparation and use of the tea plant C. sinensis.
Tea is a natural source of the amino acid theanine, methylxanthines such as caffeine and theobromine, and polyphenolic antioxidant catechins.It has almost no carbohydrates, fat or protein. It has a cooling, slightly bitter, and astringent taste.