Tea: Difference between revisions

'''Tea''' is an aromatic beverage commonly prepared by pouring hot or boiling water over cured leaves of the tea plant, ''[[Camellia sinensis]]'' After water, tea is the most widely consumed beverage in the world. It has a cooling, slightly bitter, astringent flavour which many people enjoy.

==Cultivation and harvesting==

''[[Camellia sinensis]]'' is an evergreen plant that grows mainly in tropical and subtropical climates. Some varieties can also tolerate marine climates and are cultivated as far north as Pembrokeshire in the British mainland and Washington in the United States.

==Processing and classification==

Teas can generally be divided into categories based on how they are processed. There are at least six different types of tea: [[white tea|white]], [[yellow tea|yellow]], [[green tea|green]], [[oolong]], [[black tea|black]] (called ''red tea'' in China), and [[post-fermented tea]] (or ''black tea'' for the Chinese) of which the most commonly found on the market are white, green, oolong, and black. Some varieties, such as traditional oolong tea and [[Pu-erh tea]], a post-fermented tea, can be used medicinally.

After picking, the tea leaves soon begin to wilt and [[Oxidation|oxidize]], unless they are immediately dried. The leaves turn progressively darker as their chlorophyll breaks down and tannins are released. This enzymatic oxidation process is caused by the plant's intracellular enzymes and causes the tea to darken. In tea processing, the darkening is stopped at a predetermined stage by heating, which deactivates the enzymes responsible. In the production of black teas, the halting of oxidization by heating is carried out simultaneously with drying.

Without careful moisture and temperature control during manufacture and packaging, the tea may become unfit for consumption, due to the growth of undesired molds and bacteria. At minimum, it may alter the taste and make it undesirable.

==Blending and additives==

==Origin and history==

Tea plants are native to East and South Asia, and probably originated around the meeting points of the lands of northeast India, north Burma and southwest China.

| style="background:#eee;"| Korean

|차 ''cha'' <small>₍₁₎</small>

|''ça''

| style="background:#eee;"| Lao

| style="background:#eee;"| Malayalam

| ''chāyā''

|चहा ''chahā''

|-

===Etymological observations===

* In Central Asia, Mandarin ''cha'' developed into Persian ''chay'', and this form spread with Persian trade and cultural influence.

* Russia (''chai'') encountered tea in Central Asia.

==Tea culture==

Tea may be consumed early in the day to heighten alertness; it contains theophylline and bound [[caffeine]] (sometimes called ''[[theine]]''). Decaffeinated brands are also sold.

==Preparation==

The traditional method of making or brewing a cup of tea is to place loose tea leaves, either directly or in a tea infuser, into a tea pot or teacup and pour freshly boiled water over the leaves. After a few minutes, the leaves are usually removed again, either by removing the infuser, or by straining the tea while serving.

Antioxidant content, measured by the lag time for oxidation of cholesterol, is improved by the cold-water steeping of varieties of tea.

===Black tea (Called ''red tea'' in China)===

===Premium or delicate tea===

Some teas, especially green teas and delicate oolong teas, are steeped for shorter periods, sometimes less than 30 seconds. Using a [[tea strainer]] separates the leaves from the water at the end of the brewing time if a tea bag is not being used. However, the black [[Darjeeling tea]], a premium Indian tea, needs a longer than average steeping time. Elevation and time of harvest offer varying taste profiles; proper storage and water quality also have a large impact on taste.

===Additives===

The order of steps in preparing a cup of tea is a much-debated topic, and can vary widely between cultures or even individuals. Some say it is preferable to add the milk before the tea, as the high temperature of freshly brewed tea can denature the proteins found in fresh milk, similar to the change in taste of UHT milk, resulting in an inferior-tasting beverage. Others insist it is better to add the milk after brewing the tea, as most teas need to be brewed as close to boiling as possible. The addition of milk chills the beverage during the crucial brewing phase, if brewing in a cup rather than using a pot, meaning the delicate flavor of a good tea cannot be fully appreciated. By adding the milk afterwards, it is easier to dissolve sugar in the tea and also to ensure the desired amount of milk is added, as the color of the tea can be observed. Historically, the order of steps was taken as an indication of class: only those wealthy enough to afford good-quality porcelain would be confident of its being able to cope with being exposed to boiling water unadulterated with milk.

A 2007 study published in the ''European Heart Journal'' found certain beneficial effects of tea may be lost through the addition of milk.

==Economics==

Tea is the most popular manufactured drink in the world in terms of consumption. Its consumption equals all other manufactured drinks in the world – including coffee, chocolate, soft drinks, and alcohol&nbsp;– put together. Most tea consumed outside East Asia is produced on large plantations in the hilly regions of India and Sri Lanka, and is destined to be sold to large businesses. Opposite this large-scale industrial production are many small "gardens," sometimes minuscule plantations, that produce highly sought-after teas prized by gourmets. These teas are both rare and expensive, and can be compared to some of the most expensive wines in this respect.

===Production===

In 2003, world tea production was 3.21 million tonnes annually. In 2010, world tea production reached over 4.52 million tonnes. The largest producers of tea are the People's Republic of China, India, Kenya, Sri Lanka, and Turkey.

The following table shows the amount of tea production (in tonnes) by leading countries in recent years.

!Country !!2008!!2009!!2010

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!Total!!{{formatnum:4211397}}!!{{formatnum:4242280}}!!{{formatnum:4518060}}

==Packaging==

===Tea bags===

In 1907, American tea merchant Thomas Sullivan began distributing samples of his tea in small bags of Chinese silk with a drawstring. Consumers noticed they could simply leave the tea in the bag and reuse it with fresh tea. However, the potential of this distribution/packaging method would not be fully realized until later on. During World War II, tea was rationed in the United Kingdom. In 1953 (after Rationing in the United Kingdom during and after World War II|rationing in the UK ended), Tetley launched the tea bag to the UK and it was an immediate success.

Additional reasons why bag tea is considered less well-flavored include:

* Breaking up the leaves for bags extracts flavored oils.

* The small size of the bag does not allow leaves to diffuse and steep properly.

===Loose tea===

The tea leaves are packaged loosely in a canister or other container. Rolled gunpowder tea leaves, which resist crumbling, are commonly vacuum packed for freshness in aluminized packaging for storage and retail. The portions must be individually measured by the consumer for use in a cup, mug, or teapot. This allows greater flexibility, letting the consumer brew weaker or stronger tea as desired, but convenience is sacrificed. Strainers, "tea presses", filtered teapots, and infusion bags are available commercially to avoid having to drink the floating loose leaves and to prevent over-brewing. A more traditional, yet perhaps more efficient way around this problem is to use a three-piece lidded teacup, called a [[gaiwan]]. The lid of the gaiwan can be tilted to decant the leaves while pouring the tea into a different cup for consumption.

==Gallery==

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===Bibliography===

* Kit Chow, Ione Kramer (1990): ''All the Tea in China'', China Books & Periodicals Inc. ISBN 0-8351-2194-1.

* John C. Evans (1992): ''Tea in China: The History of China's National Drink'', Greenwood Press. ISBN 0-313-28049-5

* Forbes, Andrew ; Henley, David (2011). ''China's Ancient Tea Horse Road''. Chiang Mai: Cognoscenti Books. ASIN: B005DQV7Q2

* Lu Yu (陆羽): ''Cha Jing'' (茶经) Translated and Introduced by Francis Ross. ''The Classic of Tea''. Boston: Little,  1974. x, 177p. ISBN 0-316-53450-1;  Reprinted: Ecco Press, 1997. ISBN 0880014164.

* Lysaght, Patricia. "When I makes Tea, I makes Tea: the case of Tea in Ireland". ''Ulster Folklife'', Vol. 33, 1987

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