The tea plant Camellia sinensis, which is a member of the plant family Theaceae, is a small evergreen tree that is related to the camellias commonly grown in gardens. Although there are more than 3,000 different types, or grades, of true tea that are produced, nearly all are derived from this single species. Other plants such as peppermint
and jasmine, which are also often steeped to yield a hot drink, are not true teas. Next to water, tea is said to be the most common drink in the world, with production exceeding two million tons per year worldwide.
Tea is thought to be native to China and/or Tibet, but not to India or Sri Lanka, where most commercial tea is grown today. The practice of drinking hot tea likely originated in China, and was later taken up in Japan, where elaborate tea drinking ceremonies developed. It was only much later, during the 1600s, that the export of tea to Europe began. Today, tea is consumed worldwide, and a great variety of practices has evolved regarding how and when tea is served and consumed. For example, Americans often drink tea with or after meals, adding milk, sugar, or lemon, while in Great Britain, it has long been the practice to serve tea in the late afternoon, often accompanied by cakes or biscuits.
The tea plant is grown almost exclusively for the drink that is made by brewing the flower buds and leaves. Before reaching the consumer, either as loose tea, tea bags, or bricks, a rather complex series of steps takes place. Dried tea is prepared by harvesting steps that usually include drying, rolling, crushing, fermenting, and heating. The result is the drink that is consumed, both hot and cold, primarily because of the stimulatory effect of the caffeine and the astringent effect of the tannins that the plant contains. Depending on where and how the tea is grown, when and how much of the plant is harvested, and the details of the processing, the resulting tea can take on an astounding range of tastes and colors. Commercial teas are generally of two forms—black or green—with black by far the more common. Black tea differs from green primarily because of an additional fermentation step caused by microorganisms on the dried, crushed leaves. In addition to black and green teas, other major classes of tea are produced as a result of alterations of the basic production process.
Caffeine —A bitter alkaloid present in tea, coffee, and other drinks, that acts as both a stimulant and a diuretic.
Tannin —An organic constituent of tea that influences the taste, color, and pungency.
Theaceae —A tropical and subtropical family of trees and shrubs that includes the tea plant and a variety of cultivated species, including Camellias.
Tea was originally steeped from the loose leaves, which could be added to boiling water, or through which boiling water could be poured. In North America, and increasingly elsewhere, most tea is now brewed from tea bags rather than from loose tea. By steeping tea bags for shorter or longer periods of time, the color and the strength of the tea can be controlled—yet one more example of how the final drink can be manipulated. Regardless of the type of tea, virtually all commercial teas are blends of several to many different types that have been combined in such a way—and often based on secret recipes—to achieve a particular taste and color. In addition, dried leaves or oils from other plants are sometimes added to achieve a particular taste, as in the case of Earl Grey tea. Although purists sometimes scoff at such practices, there are many teas in which interesting flavors have been achieved in this way.
In thinking about tea, students of United States history recall the Boston Tea Party of 1773. In this uprising, the tea cargo on three British ships was thrown into Boston Harbor by small group of colonists disguised as Native Americans, this to protest a tax levied by Britain’s King George III. The resulting closing of Boston Harbor by the British can be interpreted as but one of the many events of history leading to the writing of the Declaration of Independence.
Van Wyk, Ben-Erik. Food Plants of the World. Portland, Oregon: Timber Press, 2005.
Zhen, Yong-Su, ed. Tea: Bioactivity and Therapeutic Potential. New York: CRC, 2002.
Steven B. Carroll