The history of tea dates back thousands of years. Tea is even said to be the oldest plant in cultivation. It may be a surprising fact to learn that black, green and white teas all come from a common evergreen shrub native to Asia called the camellia sinensis. In the wild, the camellia sinensis plant can grow up to 60 feet tall; however cultivating practices require that the shrubs be pruned to about three feet. Much of the tea that we drink today is grown in China, Japan and India and is still harvested by hand.
Processing of Tea Leaves
Varieties of tea are determined by the processing method even though all tea comes from the same plant. During the processing of tea, leaves are exposed to different levels of oxidation and that is what determines whether a tea becomes black, green or white.
White tea leaves are the youngest and most tender leaves that are much more rare because they are only harvested at certain times of the year. No oxidation is allowed to occur in the processing of white tea. After harvest, the young tea leaves are fired immediately before any oxidation can occur which results in sweeter and naturally mild product. Because of the use of only select leaves, white tea tends to be more expensive than other tea.
Black tea is most common in the west where people often serve it sweetened, on ice or hot with cream, honey or sugar. Processing of black tea is quite different from that of white tea. Black tea leaves are fully oxidized or exposed to air until there color turns black; then fired. This “fermentation” process raised the concentration of chemicals, called tannins, which results in black tea’s characteristic strong and somewhat bitter taste.
Like white tea, green tea varieties are produced by preventing oxidation from occurring. The harvested leaves are initially steamed, which stops the fermentation process, before being fired. As it has been for centuries, green tea is the beverage of choice in many Asian countries. Green tea is yellow to green after brewing and has a mild, earthy essence. Studies indicate that green tea may be more healthful than other varieties as well.
Although many varieties exist, all tea is developed from the same plant species. The difference among teas comes from the various processing methods employed. Black, green and white tea are healthy delicious beverages that continue to be enjoyed worldwide.
17 11 2010. 17 11 10 http://www.communityipm.org/docs/Tea_Eco-Guide/13_Processing.PDF