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[[File:Camellia sinensis - Köhler–s Medizinal-Pflanzen-025.jpg|250px|thumb|Tea plant (''Camellia sinensis'') from ''Köhler's Medicinal Plants'']]

'''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.

Tea has been promoted for having a variety of positive health benefits, though generally these benefits have not been adequately demonstrated in humans.

The phrase "herbal tea" usually refers to infusions of fruit or herbs made without the tea plant, such as rosehip tea, chamomile tea or [[rooibos]] tea. Alternative phrases for this are [[tisane]] or herbal infusion, both bearing an implied contrast with "tea" as it is construed here.

==Cultivation and harvesting==
[[File:Cameron Highland Tea Plantation 2012.JPG|thumb|A tea plantation in the Cameron Highlands in Malaysia]]
[[File:Organic mountain grown tea leaf.jpg|thumb|Leaves of ''Camellia sinensis'', the tea plant]]

''[[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.

Tea plants are propagated from seed and by cutting; it takes about 4 to 12 years for a tea plant to bear seed, and about three years before a new plant is ready for harvesting. In addition to a zone 8 climate or warmer, tea plants require at least 127&nbsp;cm (50&nbsp;inches) of rainfall a year and prefer acidic soils. Many high-quality tea plants are cultivated at elevations of up to 1500m above sea level: at these heights, the plants grow more slowly and acquire a better flavor.

Only the top 1-2&nbsp;inches of the mature plant are picked. These buds and leaves are called "flushes". A plant will grow a new flush every seven to 15 days during the growing season, and leaves that are slow in development always produce better-flavored teas.

A tea plant will grow into a tree of up to 16m if left undisturbed, but cultivated plants are pruned to waist height for ease of plucking.

Two principal varieties are used: the China plant (''Camillia sinensis var. sinensis''), used for most Chinese, Formosan and Japanese teas (but not [[Pu-erh]]); and the clonal (Assam) (''Camillia sinensis var. assamic''a) tea plant , used in most Indian and other teas (but not [[Darjeeling]]). Within these botanical varieties, there are many strains and modern Indian clonal varieties. Leaf size is the chief criterion for the classification of tea plants, with three primary classifications being: [[Assam]] type, characterized by the largest leaves; China type, characterized by the smallest leaves; and Cambod, characterized by leaves of intermediate size.

==Processing and classification==

[[File:Teaprocessing.svg|thumb|right|Tea leaf processing methods]]
[[File:TeaLeaves.JPG|thumb|Fresh tea leaves of different sizes: The smaller the leaf, the more expensive the tea.]]

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.
[[Image:Group of workers harvesting tea Chakva Prokudin-Gorsky.jpg|thumb|Tea harvest on the eastern shores of the [[Black Sea]], ''circa'' 1905–15]]
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.

*[[White tea]]: Wilted and unoxidized
*[[Yellow tea]]: Unwilted and unoxidized, but allowed to yellow
*[[Green tea]]: Unwilted and unoxidized
*[[Oolong]]: Wilted, bruised, and partially oxidized
*[[Black tea]]: Wilted, sometimes crushed, and fully oxidized
*[[Post-fermented tea]]: Green tea that has been allowed to ferment

==Blending and additives==

Although single estate teas are available, almost all teas in bags and most other teas sold in the West are blends. Blending may occur in the tea-planting area (as in the case of Assam), or teas from many areas may be blended. The aim of blending is to obtain better taste, higher price, or both, as a more expensive, better-tasting tea may cover the inferior taste of cheaper varieties.

Some teas are not pure varieties, but have been enhanced through additives or special processing. Tea is highly receptive to inclusion of various aromas; this may cause problems in processing, transportation, and storage, but also allows for the design of an almost endless range of scented and flavored variants, such as bergamot ([[Earl Grey tea|Earl Grey]]), vanilla, and caramel.

==Content==
Tea contains catechins, a type of antioxidant. In a freshly picked tea leaf, catechins can comprise up to 30% of the dry weight. Catechins are highest in concentration in white and green teas, while black tea has substantially fewer due to its oxidative preparation. Research by the U.S. Department of Agriculture has suggested the levels of antioxidants in green and black tea do not differ greatly, as green tea has an oxygen radical absorbance capacity (ORAC) of 1253 and black tea an ORAC of 1128 (measured in μmol TE/100 g). Antioxidant content, measured by the lag time for oxidation of cholesterol, is improved by the cold water steeping of varieties of tea.

Tea also contains L-theanine, and the stimulant [[caffeine]] at about 3% of its dry weight, translating to between 30&nbsp;mg and 90&nbsp;mg per 8 oz (250 ml) cup depending on type, brand, and brewing method.

Tea also contains small amounts of theobromine and theophylline. Due to modern environmental pollution, fluoride and aluminium have also been found to occur in tea, with certain types of [[Tea brick|brick tea]] made from old leaves and stems having the highest levels. This occurs due to the tea plant's high sensitivity to and absorption of environmental pollutants.

Although tea contains various types of polyphenols and tannin, it does not contain tannic acid. Tannic acid is not an appropriate standard for any type of tannin analysis because of its poorly defined composition.

==Origin and history==

[[Image:Gorskii 03992u.jpg|thumb|Tea weighing station north of [[Batumi]], [[Russian Empire]] before 1915]]

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.

Although there are tales of tea's first use as a beverage, no one is sure of its exact origins. The first recorded drinking of tea is in China, with the earliest records of tea consumption dating to the 10th century BC. It was already a common drink during the Qin Dynasty (third century BC) and became widely popular during the Tang Dynasty, when it was spread to Korea, Japan and possibly Vietnam, although when the Vietnamese began to drink tea is not recorded.

Tea was imported to Europe during the Portuguese expansion of the 16th century, at which time it was termed ''chá''. In 1750, tea experts travelled from China to the Azores, and planted tea, along with jasmines and mallows, to give it aroma and distinction. Both green and black tea continue to grow in the islands, which are the main suppliers to continental Portugal. Catherine of Braganza, wife of Charles II, took the tea habit to Great Britain around 1660, but tea was not widely consumed in Britain until the 19th century. In Ireland, tea had become an everyday beverage for all levels of society by the late 19th century, but it was first consumed as a luxury item on special occasions, such as religious festivals, wakes, and domestic work gatherings such as quiltings.

The first European to successfully transplant tea to the Himalayas, Robert Fortune, was sent by the East India Company on a mission to China to bring the tea plant back to Great Britain. He began his journey in high secrecy as his mission occurred in the lull between the two Anglo-Chinese Wars or opium wars, and westerners were not in high regard at the time.

==Health effects==

Tea contains a large number of potentially bioactive chemicals, including flavinoids, amino acids, vitamins, caffeine and several polysaccharides, and a variety of health effects have been proposed and investigated. It has been suggested that green and black tea may protect against cancer, though the catechins found in green tea are thought to be more effective in preventing certain obesity-related cancers such as liver and colorectal while both green and black tea may protect against cardiovascular disease.

Numerous recent epidemiological studies have been conducted to investigate the effects of green tea consumption on the incidence of human cancers.  These studies suggest significant protective effects of green tea against oral, pharyngeal, esophageal, prostate, digestive, urinary tract, pancreatic, bladder, skin, lung, colon, breast, and liver cancers, and lower risk for cancer metastasis and recurrence.

==The word "tea"==

The Chinese character for tea is [[wikt:茶|茶]]. It is pronounced differently in the various Chinese dialects. Most pronounce it along the lines of ''cha'' (Mandarin has ''chá''), but the Min varieties along the central coast of China and in Southeast Asia pronounce it like ''te''. These two pronunciations of the Chinese word for tea have made their separate ways into other languages around the world:
*'''Te''' is from ''tê'' in the Amoy dialect, spoken in Fujian Province and Taiwan. It reached the West from the port of Xiamen (Amoy), once a major point of contact with Western European traders such as the Dutch, who spread it to Western Europe.
*'''Cha''' is from the Cantonese ''chàh'', spoken in Guangzhou (Canton) and the ports of Hong Kong and Macau, also major points of contact, especially with the Portuguese, who spread it to India in the 16th century. The Korean and Japanese words ''cha'' come from the Mandarin ''chá''.

The widespread form '''''chai''''' comes from Persian چای ''chay''. This derives from Mandarin ''chá'', which passed by the silk road to Central Asia and Persia, where it picked up the Persian grammatical suffix ''-yi'' before passing on to Russian, Arabic, Urdu, Turkish, etc.

English has all three forms: ''cha'' or ''char'', attested from the 16th century; ''tea'', from the 17th; and ''chai'', from the 20th.

Languages in more intense contact with Chinese, Sinospheric languages like Vietnamese, Zhuang, Tibetan, Korean, and Japanese, may have borrowed their words for tea at an earlier time and from a different variety of Chinese, so-called Sino-Xenic pronunciations. Korean and Japanese, for example, retain early pronunciations of ''ta'' and ''da''. ''Ta'' comes from the Tang Dynasty court at Chang'an: that is, from Middle Chinese. Japanese ''da'' comes from the earlier Southern Dynasties court at Nanjing, a place where the consonant was still voiced, as it is today in neighboring Shanghainese ''zo''. Vietnamese and Zhuang have southern ''cha''-type pronunciations.

===Derivatives of ''te''===

{| class="wikitable"
|-
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
|-
| style="background:#eee;"| Afrikaans
|''tee''
| style="background:#eee;"| Armenian
|թեյ ''tey''
| style="background:#eee;"| Euskara
|''tea''
| style="background:#eee;"| Catalan
|''te''
| style="background:#eee;"| Czech
|''té'' or ''thé'' <small><sub>(1)</sub></small>
|-
| style="background:#eee;"| Danish
|''te''
| style="background:#eee;"| Dutch
|''thee''
| style="background:#eee;"| English
|''tea''
| style="background:#eee;"| Esperanto
|''teo''
| style="background:#eee;"| Estonian
|''tee''
|-
| style="background:#eee;"| Faroese
|''te''
| style="background:#eee;"| Finnish
|''tee''
| style="background:#eee;"| French
|''thé''
| style="background:#eee;"| West Frisian
|''tee''
| style="background:#eee;"| Galician
|''té''
|-
| style="background:#eee;"| German
|''Tee''
| style="background:#eee;"| Greek
|τέϊον ''téïon''
| style="background:#eee;"| Hebrew
|תה, ''te''
| style="background:#eee;"| Hungarian
|''tea''
| style="background:#eee;"| Icelandic
|''te''
|-
| style="background:#eee;"| Indonesian
|''teh''
| style="background:#eee;"| Irish
|''tae''
| style="background:#eee;"| Italian
| ''tè'', ''thè'' or ''the''
| style="background:#eee;"| Javanese
| ''tèh''
| style="background:#eee;"| Khmer
| តែ ''tae''
|-
| style="background:#eee;"| Latin
| ''thea''
| style="background:#eee;"| Latvian
|''tēja''
| style="background:#eee;"| Leonese
| ''té''
| style="background:#eee;"| Limburgish
|''tiè''
| style="background:#eee;"| Low Saxon
|''Tee''
|-
| style="background:#eee;"| Malay
|''teh''
| style="background:#eee;"| Malayalam
|തേയില ''Thēyila''
| style="background:#eee;"| Maltese
| ''tè''
| style="background:#eee;"| Mongolian
|цай ''tsai''
| style="background:#eee;"| Norwegian
|''te''
|-
| style="background:#eee;"| Occitan
|''tè''
| style="background:#eee;"| Polish
|''herbata''<small><sub>(2)</sub></small>
| style="background:#eee;"| Kannada
|''ಚಹಾ''
| style="background:#eee;"| Scots Gaelic
|''tì'', ''teatha''
| style="background:#eee;"| Sinhalese
|'' té ''තේ
|-
| style="background:#eee;"| Spanish
|''té''
| style="background:#eee;"| Scots
|''tea''
| style="background:#eee;"| Sundanese
|''entèh''
| style="background:#eee;"| Swedish
|''te''
| style="background:#eee;"| Tamil
|தேநீர் ''theneer'' <small><sub>(3)</sub></small>
|-
| style="background:#eee;"| Telugu
|తేనీరు ''theneeru''
| style="background:#eee;"| Welsh
|''te''
| style="background:#eee;"| 
|
| style="background:#eee;"| 
|
| style="background:#eee;"| 
|
|}
<small>Notes:</small>
* <small><sup>(1)</sup></small> ''té'' or ''thé'', but this term is considered archaic and is a literary expression; since roughly the beginning of the 20th century, ''čaj'' is used for "tea" in Czech language, see the following table
* <small><sup>(2)</sup></small> from Latin ''herba thea''
* <small><sup>(3)</sup></small> ''neer'' means water; ''theyilai'' means "tea leaf" (ilai = leaf)

===Derivatives of ''ta''===
{| class="wikitable"
|-
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
|-
| style="background:#eee;"| Japanese
| だ ''da'', た ''ta'' <small><sub>(1)</sub></small>
| style="background:#eee;"| Korean
| 다 ''da''<small><sub>(1)</sub></small>
|}
* <small><sup>(1)</sup></small> ''cha'' is an alternative pronunciation of "tea" in Japanese and Korean; see below

===Derivatives of ''cha''===

{| class="wikitable"
|-
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
|-
| style="background:#eee;"| Assamese
|চাহ ''sah''
| style="background:#eee;"| Bangla
|চা ''cha''
| style="background:#eee;"| Kapampangan
|''cha''
| style="background:#eee;"| Cebuano
|''tsa''
| style="background:#eee;"| English
|''cha'' or ''char''
|-
| style="background:#eee;"| Gujarati
|ચા ''chā''
| style="background:#eee;"| Japanese
|チャ ''cha'', さ ''sa'' <small><sub>(1)</sub></small>
| style="background:#eee;"| Kannada
|ಚಹಾ  ''chahā''
| style="background:#eee;"| Khasi
|''sha''
| style="background:#eee;"| Konkani
|चा ''chā''
|-
| style="background:#eee;"| Korean
|차 ''cha'' <small><sub>(1)</sub></small>
|style="background:#eee;" |  [[Kurdish language|Kurdish]]
|''ça''
| style="background:#eee;"| Lao
|ຊາ ''saa''
| style="background:#eee;"| Malayalam
| ''chāyā''
| style="background:#eee;"| [[Marathi language|Marathi]]
|चहा ''chahā''
|-
| style="background:#eee;"| Oriya
|ଚା ''cha''
| style="background:#eee;"|Persian
|چا ''chā''
| style="background:#eee;"| Punjabi
|چا ਚਾਹ ''chāh''
| style="background:#eee;"| Portuguese
|''chá''
| style="background:#eee;"| Sindhi
|''chahen چانهه''
|-
| style="background:#eee;"| Somali
|''shaah''
| style="background:#eee;"| Sylheti
|''sa''
| style="background:#eee;"| Tagalog
|''tsaa''
| style="background:#eee;"| Thai
|ชา ''cha''
| style="background:#eee;"| Tibetan
|ཇ་ ''ja''
|-
| style="background:#eee;"| Turkish
|''çay''
| style="background:#eee;"| Vietnamese
|''trà'' and ''chè'' <small><sub>(2)</sub></small>
| style="background:#eee;"|
|
| style="background:#eee;"|
|
| style="background:#eee;"|
|}
<small>Notes: </small>
* <small><sup>(1)</sup></small>  The main pronunciations of [[wikt:茶|茶]] in Korea and Japan are [[wikt:차|차]] ''cha'' and [[wikt:ちゃ|ちゃ]] ''cha'', respectively. (Japanese ''ocha'' ([[wikt:おちゃ|おちゃ]]) is honorific.) These are connected with the pronunciations at the capitals of the Song and Ming dynasties.
* <small><sup>(2)</sup></small> ''Trà'' and ''chè'' are variant pronunciations of 茶; the latter is used mainly in northern Vietnam and describes a tea made with freshly picked leaves.

===Derivatives of ''chay''===
{| class="wikitable"
|-
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
! style="width:85px;"|Language
! style="width:85px;"|Name
|-
| style="background:#eee;"| Chechen
|''чай''
| style="background:#eee;"| Albanian
|''çaj''
| style="background:#eee;"| Amharic
|ሻይ ''shai''
| style="background:#eee;"| Arabic
|شاي ''shāy''
| style="background:#eee;"| Aramaic
|ܟ݈ܐܝ ''chai''
|-
| style="background:#eee;"| Armenian (Eastern Dialect)
|չայ ''chāi''
| style="background:#eee;"| Azerbaijani
|''çay''
| style="background:#eee;"| Bosnian
|''čaj''
| style="background:#eee;"| Bulgarian
|чай ''chai''
| style="background:#eee;"| Croatian
|''čaj''
|-
| style="background:#eee;"| Czech
|''čaj'' <sub>(2)</sub>
| style="background:#eee;"| English
|''chai''
| style="background:#eee;"| Finnish dialectal
|''tsai'', ''tsaiju'', ''saiju'' or ''saikka''
| style="background:#eee;"| Georgian
|ჩაი ''chai''
| style="background:#eee;"| Greek
|τσάι ''tsái''
|-
| style="background:#eee;"| Hindi
|चाय ''chāy''
| style="background:#eee;"| Kazakh
|шай ''shai''
| style="background:#eee;"| Kyrgyz
|чай ''chai''
| style="background:#eee;"| Kinyarwanda
|''icyayi''
| style="background:#eee;"| Ladino
|צ'יי ''chai''
|-
| style="background:#eee;"| Macedonian
|''чај''
| style="background:#eee;"| Malayalam
|ചായ ''chaaya''
| style="background:#eee;"| Mongolian
|цай ''tsai''
| style="background:#eee;"| Nepali
|''chiyā'' चिया
| style="background:#eee;"| Pashto
|چای ''chay''
|-
| style="background:#eee;"| Persian
|چای ''chāī'' <small><sub>(1)</sub></small>
| style="background:#eee;"| Romanian
|''ceai''
| style="background:#eee;"| Russian
|чай ''chai''
| style="background:#eee;"| Serbian
|чај ''čaj''
| style="background:#eee;"| Slovak
|''čaj''
|-
| style="background:#eee;"| Slovene
|''čaj''
| style="background:#eee;"| Swahili
|''chai''
| style="background:#eee;"| Tajik
|чой ''choy''
| style="background:#eee;"| Tatar
|''çäy''
| style="background:#eee;"| Tlingit
|''cháayu''
|-
| style="background:#eee;"| Telugu
|''Tenneru''
| style="background:#eee;"| Turkish
|''çay''
| style="background:#eee;"| Turkmen
|''çay''
| style="background:#eee;"| Ukrainian
|чай ''chai''
| style="background:#eee;"| Urdu
|چائے ''chai''
|-
| style="background:#eee;"| Uzbek
|''choy''
|}
<small>Notes: </small>
* <small><sup>(1)</sup></small> Derived from the earlier pronunciation چا ''cha''.

===Etymological observations===
The different words for tea fall into two main groups: "''te''-derived" ([[Min Chinese|Min]]) and "''cha''-derived" ([[Cantonese]] and [[Mandarin Chinese|Mandarin]]).<ref name=oed/> The words that various languages use for "tea" reveal where those nations first acquired their tea and tea culture.
* Portuguese traders were the first Europeans to import the herb in large amounts. The Portuguese borrowed their word for tea (''cha'') from Cantonese in the 1550s via their trading posts in the south of China, especially [[Macau]].<ref name="OEDTEA" />
* 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.

* The Dutch word for "tea" (''thee'') comes from the Min dialect. The Dutch may have borrowed their word for tea through trade directly from Fujian, or from Fujianese or Malay traders in Java. From 1610 on, the Dutch played a dominant role in the early European tea trade, via the Dutch East India Company, influencing other languages to use the Dutch word for tea. Other European languages whose words for tea derive from the Min dialect (via Dutch) include English, French (''thé''), Spanish (''te''), and German (''Tee'').

* The Dutch first introduced tea to England in 1644. By the 19th century, most British tea was purchased directly from merchants in Canton, whose population uses ''cha'', though English never replaced its Dutch-derived Min word for tea.

At times, a ''te'' form will follow a ''cha'' form, or ''vice versa'', giving rise to both in one language, at times one an imported variant of the other.
* In North America, the word ''chai'' is used to refer almost exclusively to the Indian ''masala chai'' (spiced tea) beverage, in contrast to tea itself.
* The inverse pattern is seen in Moroccan colloquial Arabic (Darija), ''ash-shay'' means "generic, or black Middle Eastern tea" whereas ''at-tay'' refers particularly to Zhejiang or Fujian green tea with fresh mint leaves. The Moroccans are said to have acquired this taste for green tea— unique in the Arab world— for East Chinese green tea after the ruler Mulay Hassan exchanged some European hostages captured by the Barbary pirates for a whole ship of Chinese tea. See Moroccan tea culture.
* The colloquial Greek word for tea is ''tsáï'', from Slavic ''chai''.  Its formal equivalent, used in earlier centuries, is ''téïon'', from ''tê''.
* The Polish word for a tea-kettle is ''czajnik'', which could be derived directly from ''chai'' or from the cognate Russian word. However, tea in Polish is ''herbata'', which, as well as Lithuanian ''arbata'', was derived from the Latin ''herba thea'', meaning "tea herb".
* The normal word for tea in Finnish is ''tee'', which is a Swedish loan. However, it is often colloquially referred to, especially in Eastern Finland and in Helsinki, as ''tsai'', ''tsaiju'', ''saiju'' or ''saikka'', which is cognate to Russian word ''chai''. The latter word refers always to black tea, while green tea is always ''tee''.
* In Ireland, or at least in Dublin, the term ''cha'' is sometimes used for "tea", as is pre-vowel-shift pronunciation "tay" (from which the Irish Gaelic word ''tae'' is derived. ''Char'' was a common slang term for tea throughout British Empire and Commonwealth military forces in the 19th and 20th centuries, crossing over into civilian usage.
* The British English slang word "char" for "tea" arose from its Cantonese Chinese pronunciation "''cha''" with its spelling affected by the fact that ''ar'' is a more common way of representing the phoneme in British English.`

==Tea culture==
[[File:Masala Chai.JPG|thumb|''[[Masala chai]]'' from the Indian subcontinent]]

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.

While tea is the second most consumed beverage on Earth after water, in many cultures it is also consumed at elevated social events, such as afternoon tea and the tea party. [[Tea ceremony|Tea ceremonies]] have arisen in different cultures, such as the [[Chinese tea ceremony|Chinese]] and [[Japanese Tea Ceremony|Japanese]] tea ceremonies, each of which employs traditional techniques and ritualized protocol of brewing and serving tea for enjoyment in a refined setting. One form of Chinese tea ceremony is the ''[[Gongfu tea ceremony]]'', which typically uses small [[Yixing clay teapot]]s and [[oolong tea]].

Ireland has, for a long time, been one of the biggest per-capita consumers of tea in the world. The national average is four cups per person per day, with many people drinking six cups or more. Tea in Ireland is usually taken with milk and/or sugar and is slightly spicier and stronger than the traditional English Blend. The two main brands of tea sold in Ireland are Lyons and Barry's. The Irish love of tea is perhaps best illustrated by the stereotypical housekeeper, Mrs Doyle in the popular sitcom ''Father Ted''.

Tea is prevalent in most cultures in the Middle East. In Arab culture, tea is a focal point for social gatherings.

In Pakistan, both black and green teas are popular and are known locally as ''sabz chai'' and ''kahwah'', respectively. The popular green tea called ''kahwah'' is often served after every meal in the Pashtun belt of Balochistan and in Khyber Pakhtunkhwa, which is where the Khyber Pass of the Silk Road is found. In the Kashmir region, Kashmiri chai or ''noon chai'', a pink, milky tea with pistachios and cardamom, is consumed primarily at special occasions, weddings, and during the winter months when it is sold in many kiosks. In Central and Southern Punjab along with metropolitan Sindh, tea with milk and sugar (sometimes with cardamoms, etc.), commonly referred as ''chai'', is widely consumed. It is the most common beverage of working class and households. In the northern Pakistani regions of Chitral and Gilgit-Baltistan, a salty, buttered Tibetan-style tea is consumed.  In Iranian culture, tea is so widely consumed, it is generally the first thing offered to a household guest.

In the United States and Canada, 80% of tea is consumed cold, as iced tea. Sweet tea is a cultural symbol of the southern US, and is common in that portion of the country.

Switzerland has its own unique blend of iced tea, made with the basic ingredients like black tea, sugar, lemon juice and mint, but a variety of Alp herbs and hemp are also added to the concoction. Apart from classic flavors like lemon and peach, exotic flavors like jasmine and lemongrass are also very popular.

In India, tea is one of the most popular hot beverages. It is consumed daily in almost all homes, offered to guests, consumed in high amounts in domestic and official surroundings, and is made with the addition of milk with or without spices. It is also served with biscuits dipped in the tea and eaten before consuming the tea. More often than not, it is drunk in "doses" of small cups (referred to as "Cutting" chai if sold at street tea vendors) rather than one large cup. On April 21, 2012, the Deputy Chairman of Planning Commission (India), Montek Singh Ahluwalia, said tea would be declared as national drink by April 2013. The move is expected to boost the tea industry in the country. Speaking on the occasion, [[Assam]] Chief Minister Tarun Gogoi said a special package for the tea industry would be announced in the future to ensure its development.

In the United Kingdom, especially England, it is consumed daily and often by a majority of people across the country, and indeed is perceived as one of Britain's cultural beverages. In British homes, it is customary good manners for a host to offer tea to guests soon after their arrival. Tea is generally consumed at home; outside the home in cafés. Afternoon tea with cakes on fine porcelain is a cultural stereotype, sometimes available in quaint tea-houses. In southwest England, many cafes serve a 'cream tea', consisting of scones, clotted cream, and jam alongside a pot of tea. Throughout England, and Scotland, 'tea' may also refer to the evening meal.

In Burma (Myanmar), tea is consumed not only as hot drinks, but also as sweet tea and green tea known locally as ''laphet-yay'' and ''laphet-yay-gyan'', respectively. Pickled tea leaves, known locally as ''laphet'', are also a national delicacy. Pickled tea is usually eaten with roasted sesame seeds, crispy fried beans, roasted peanuts and fried garlic chips.

==Preparation==
[[Image:Teapot P1100116.jpg|thumb|Tea kettle over hot coal at a tea house in Jiufen, Taiwan]]

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.

Most green teas should be allowed to steep for about two or three minutes, although some types of tea require as much as ten minutes, and others as little as 30 seconds. The strength of the tea should be varied by changing the amount of tea leaves used, not by changing the steeping time. The amount of tea to be used per amount of water differs from tea to tea, but one basic recipe may be one slightly heaped teaspoon of tea (about 5 ml) for each teacup of water (200–240 ml) (7–8&nbsp;oz) prepared as above. Stronger teas, such as Assam, to be drunk with milk, are often prepared with more leaves, and more delicate high-grown teas such as a Darjeeling are prepared with somewhat fewer (as the stronger mid-flavors can overwhelm the champagne notes).

The best temperature for brewing tea depends on its type. Teas that have little or no oxidation period, such as a green or white tea, are best brewed at lower temperatures, between 65 and 85°C, while teas with longer oxidation periods should be brewed at higher temperatures around 100°C. The higher temperatures are required to extract the large, complex, flavorful phenolic molecules found in fermented tea. In addition, boiling reduces the dissolved oxygen content of water. Dissolved oxygen would otherwise react with phenolic molecules to turn them brown and reduce their potency as antioxidants. To preserve the antioxidant potency, especially for green and white teas brewed at a lower temperature, water should be boiled vigorously to boil off any dissolved oxygen and then allowed to cool to the appropriate temperature before adding to the tea. An additional health benefit of boiling water before brewing tea is the sterilization of the water and reduction of any dissolved Volatile Organic Compound, chemicals which are often harmful.

{| class="wikitable"
|-
|  '''Type'''
!  Water temp.
!  Steep time
!  Infusions
|-
|  White tea
|  65 – 70°C
|  1–2 minutes
|  3
|-
|  Yellow tea
|  70 – 75°C
|  1–2 minutes
|  3
|-
|  Green tea
|  60 – 80°C
|  1–2 minutes
|  4-6
|-
|  Oolong tea
|  80 – 95°C
|  2–3 minutes
|  4-6
|-
|  Black tea
|  95 – 100°C
|  2–3 minutes
|  2-3
|-
|  Pu'er tea
|  95 – 100°C
|  3 - 5 minutes
|  Several
|-
|  Tisanes
|  90 – 100°C
|  3–6 minutes
|  Varied
|}

Some tea sorts are often brewed several times using the same leaves. Historically in China, tea is divided into a number of infusions. The first infusion is immediately poured out to wash the tea, and then the second and further infusions are drunk. The third through fifth are nearly always considered the best infusions of tea, although different teas open up differently and may require more infusions of hot water to produce the best flavor.

One way to taste a tea, throughout its entire process, is to add hot water to a cup containing the leaves and after about 30 seconds to taste it. As the tea leaves unfold (known as "The Agony of the Leaves"), they give up various parts of themselves to the water and thus the taste evolves. Continuing this from the very first flavors to the time beyond which the tea is quite stewed will allow an appreciation of the tea throughout its entire length.

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

[[Image:Cup of Earl Gray.jpg|thumb|right|Black tea infusion]]

===Black tea (Called ''red tea'' in China)===
In the West, water for black tea is usually added near the boiling point of water, at around 99°C (210°F). Many of the active substances in black tea do not develop at temperatures lower than 90°C. Lower temperatures are used for some more delicate teas. The temperature will have as large an effect on the final flavor as the type of tea used. The most common fault when making black tea is to use water at too low a temperature. Since boiling point drops with increasing altitude, it is difficult to brew black tea properly in mountainous areas. It is also recommended that the teapot be warmed before preparing tea, easily done by adding a small amount of boiling water to the pot, swirling briefly, then discarding it. In the West, black teas are usually brewed for about four minutes and are usually not allowed to steep for less than 30 seconds or more than about five minutes (a process known as brewing or mashing in Britain). In many regions of the world, however, boiling water is used and the tea is often stewed. For example in India, black tea is often boiled for fifteen minutes or longer as a strong brew is preferred for making Masala chai. When the tea has brewed long enough to suit the tastes of the drinker, it should be strained while serving. The popular varieties of black (red) tea include [[Assam tea]], [[Nepal tea]], [[Darjeeling tea]], [[Nilgiri tea]], [[Turkish tea]] and [[Tea production in Sri Lanka|Ceylon tea]].

===Green tea===
Water for green tea, according to regions of the world that prefer mild tea, should be around 80 to 85°C; the higher the quality of the leaves, the lower the temperature. Hotter water will produce a bitter taste. However, this is the method used in many regions of the world, such as North Africa or Central Asia, where bitter tea is appreciated. For example, in Morocco, green tea is steeped in boiling water for 15 minutes. In the West and Far East, a milder tea is appreciated. The container in which the tea is steeped, the mug or teapot, is often warmed beforehand so the tea does not immediately cool down. High-quality green and white teas can have new water added as many as five or more times, depending on variety, at increasingly higher temperatures.

===Oolong tea===
[[Oolong]] teas should be brewed around 85 to 95° C, and again the brewing vessel should be warmed before pouring in the water. [[Yixing clay|Yixing purple clay]] teapots are the traditional brewing-vessel for oolong tea. For best results, use spring water, as the minerals in spring water tend to bring out more flavor in the tea. High quality oolong can be brewed multiple times from the same leaves, and unlike green tea, it improves with reuse. It is common to brew the same leaves three to five times, the third steeping usually being the best.

===Premium or delicate tea===
[[File:Teacup&Strainer.JPG|thumb|A strainer is often used when tea is made with tea-leaves in a teapot.]]
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.

===Pu-erh tea===
[[Pu-erh]] teas require boiling water for infusion. Some prefer to quickly rinse pu-erh for several seconds with boiling water to remove tea dust which accumulates from the aging process, then infuse it at the boiling point 100°C , and allow it to steep from 30 seconds to five minutes.

===Serving===
To preserve the pretannin tea without requiring it all to be poured into cups, a second teapot may be used. The steeping pot is best unglazed earthenware; Yixing pots are the best known of these, famed for the high quality clay from which they are made. The serving pot is generally porcelain, which retains the heat better. Larger teapots are a post-19th century invention, as tea before this time was very rare and very expensive. Experienced tea-drinkers often insist the tea should not be stirred around while it is steeping (sometimes called winding or mashing in the UK). This, they say, will do little to strengthen the tea, but is likely to bring the tannins out in the same way that brewing too long will do. For the same reason, one should not squeeze the last drops out of a teabag; if stronger tea is desired, more tea leaves should be used.

===Additives===

[[Image:Nice Cup of Tea.jpg|thumb|Tea is sometimes taken with milk]]The addition of milk to tea in Europe was first mentioned in 1680 by the epistolist Madame de Sévigné. Many teas are traditionally drunk with milk in cultures where dairy products are consumed. These include Indian [[masala chai]] and British tea blends. These teas tend to be very hearty varieties of black tea which can be tasted through the milk, such as Assams, or the East Friesian blend. Milk is thought to neutralize remaining tannins and reduce acidity. The Han Chinese do not usually drink milk with tea (or indeed use milk at all) but the Manchus do, and the elite of the Qing Dynasty of the Chinese Empire continued to do so. Hong Kong-style milk tea is based on British colonial habits. Tibetans and other Himalayan peoples traditionally drink tea with milk or yak butter and salt. In Eastern European countries (Russia, Poland and Hungary) and in Italy, tea is commonly served with lemon juice. In Poland, tea with milk is called a ''bawarka'' ("Bavarian style"), and is often drunk by pregnant and nursing women.

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.

[[Image:Minttea.JPG|thumb|upright|Moroccan tea being served: It is poured from a distance to produce a foam on the tea.]]

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

Many flavourings are added to varieties of tea during processing. Among the best known are Chinese [[jasmine tea]], with jasmine oil or flowers, the spices in Indian masala chai, and [[Earl Grey tea]], which contains oil of [[bergamot orange|bergamot]]. A great range of modern flavours have been added to these traditional ones. In eastern India, people also drink lemon tea or lemon masala tea. Lemon tea simply contains hot tea with lemon juice and sugar. Masala lemon tea contains hot tea with roasted cumin seed powder, lemon juice, black salt and sugar, which gives it a tangy, spicy taste. Adding a piece of ginger when brewing tea is a popular habit of Sri Lankans,who also use other different types of spices such as cinnamon to sweeten the aroma.

Other popular additives to tea by the tea-brewer or drinker include sugar, liquid honey or a solid Honey Drop, agave nectar, fruit jams, and mint. In China, sweetening tea was traditionally regarded as a feminine practice. In colder regions, such as Mongolia, Tibet and Nepal, butter is added to provide necessary calories. Tibetan butter tea contains rock salt and ''dre'' (yak) butter, which is then churned vigorously in a cylindrical vessel closely resembling a butter churn. The same may be said for salt tea, which is consumed in some cultures in the Hindu Kush region of northern Pakistan.

Alcohol, such as whisky or brandy, may also be added to tea.

The flavor of the tea can also be altered by pouring it from different heights, resulting in varying degrees of aeration. The art of high-altitude pouring is used principally by people in Northern Africa (e.g. Morocco, Algeria, Mauritania and Libya), but also in West Africa (e.g. Guinea, Mali, Senegal) and can positively alter the flavor of the tea, but it is more likely a technique to cool the beverage destined to be consumed immediately. In certain cultures, the tea is given different names depending on the height from which it is poured. In Mali, gunpowder tea is served in series of three, starting with the highest oxidization or strongest, unsweetened tea (cooked from fresh leaves), locally referred to as "strong like death", followed by a second serving, where the same tea leaves are boiled again with some sugar added ("pleasant as life"), and a third one, where the same tea leaves are boiled for the third time with yet more sugar added ("sweet as love"). Green tea is the central ingredient of a distinctly Malian custom, the "Grin", an informal social gathering that cuts across social and economic lines, starting in front of family compound gates in the afternoons and extending late into the night, and is widely popular in [[Bamako]] and other large urban areas.

In Southeast Asia, particularly in Malaysia, the practice of pouring tea from a height has been refined further using black tea to which condensed milk is added, poured from a height from one cup to another several times in alternating fashion and in quick succession, to create a tea with entrapped air bubbles creating a frothy "head" in the cup. This beverage, ''teh tarik'', literally, "pulled tea", has a creamier taste than flat milk tea and is extremely popular in the region. Tea pouring in Malaysia has been further developed into an art form in which a dance is done by people pouring tea from one container to another, which in any case takes skill and precision. The participants, each holding two containers, one full of tea, pour it from one to another. They stand in lines and squares and pour the tea into each other's pots. The dance must be choreographed to allow anyone who has both pots full to empty them and refill those of whoever has no tea at any one point.

==Economics==
[[Image:Tea factory, Pinglin.jpg|thumb|Tea factory in Taiwan]]

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.

India is the world's largest tea-drinking nation, although the per capita consumption of tea remains a modest 750&nbsp;grams per person every year. Turkey, with 2.5&nbsp;kg of tea consumed per person per year, is the world's greatest per capita consumer.

===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.
[[File:WorldTeaProductionFAO2008.svg|thumb|Percentage of total tea production in 2008]]

[[Image:Tea Production 2007.png|thumb|Percentage of total global tea production by country in 2007]]

The following table shows the amount of tea production (in tonnes) by leading countries in recent years.
Data are generated by the Food and Agriculture Organization of the United Nations as of February 2012.
{| class="wikitable sortable"
|-
!Country !!2008!!2009!!2010
|-
| China||align="right"|{{formatnum:1274984}}||align="right"|{{formatnum:1375780}}||align="right"|{{formatnum:1467467}}
|-
| India||align="right"|{{formatnum:987000}}||align="right"|{{formatnum:972700}}||align="right"|{{formatnum:991180}}
|-
| Kenya||align="right"|{{formatnum:345800}}||align="right"|{{formatnum:314100}}||align="right"|{{formatnum:399000}}
|-
| Sri Lanka||align="right"|{{formatnum:318700}}||align="right"|{{formatnum:290000}}||align="right"|{{formatnum:282300}}
|-
| Turkey||align="right"|{{formatnum:198046}}||align="right"|{{formatnum:198601}}||align="right"|{{formatnum: 235000}}
|-
| Vietnam||align="right"|{{formatnum:173500}}||align="right"|{{formatnum:185700}}||align="right"|{{formatnum:198466}}
|-
| Iran||align="right"|{{formatnum:165717}}||align="right"|{{formatnum:165717}}||align="right"|{{formatnum:165717}}
|-
| Indonesia||align="right"|{{formatnum:150851}}||align="right"|{{formatnum:146440}}||align="right"|{{formatnum:150000}}
|-
| Argentina||align="right"|{{formatnum:80142}}||align="right"|{{formatnum:71715}}||align="right"|{{formatnum:88574}}
|-
| Japan||align="right"|{{formatnum:96500}}||align="right"|{{formatnum:86000}}||align="right"|{{formatnum:85000}}
|- class="sortbottom"
!Total!!{{formatnum:4211397}}!!{{formatnum:4242280}}!!{{formatnum:4518060}}
|}

====Certification====
Workers who pick and pack tea on plantations in developing countries can face harsh working conditions and can earn below the living wage.

A number of bodies independently certify the production of tea. Tea from certified estates can be sold with a certification label on the pack. The most important certification schemes are Rainforest Alliance, Fairtrade, UTZ Certified, and Organic. All these schemes certify other crops (such as coffee, cocoa and fruit), as well. Rainforest Alliance certified tea is sold by Unilever brands Lipton and PG Tips in Western Europe, Australia and the US. Fairtrade certified tea is sold by a large number of suppliers around the world. UTZ Certified announced a partnership in 2008 with Sara Lee brand Pickwick tea.

Production of organic tea is rising;  tons of organic tea were sold in 1999. The majority of this tea (about 75%) is sold in France, Germany, Japan, the United Kingdom and the United States.

===Trade===
According to the FAO in 2007, the largest importer of tea, by weight, was the Russian Federation, followed by the United Kingdom, Pakistan, and the United States.
Kenya, China, India and Sri Lanka were the largest exporters of tea in 2007 (with exports of: 374229, 292199, 193459 and 190203 tonnes respectively). The largest exporter of black tea in the world is Kenya, while the largest producer (and consumer) of black tea in the world is India.

==Packaging==
===Tea bags===
[[Image:Tea bags.jpg|thumb|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.

Tea leaves are packed into a small envelope (usually composed of paper) known as a tea bag. The use of tea bags is easy and convenient, making them popular for many people today. However, the use of tea bags has negative aspects, as well. The tea used in tea bags is commonly fannings or "dust", the waste product produced from the sorting of higher quality loose leaf tea. However, this is not true for all brands of tea; many high quality specialty teas are available in bag form. Tea aficionados commonly believe this method provides an inferior taste and experience. The paper used for the bag may also be tasted, which can detract from the tea's own flavor. Because fannings and dust are a lower quality of the tea to begin with, the tea found in tea bags is less finicky when it comes to brewing time and temperature.

Additional reasons why bag tea is considered less well-flavored include:
* Dried tea loses its flavor quickly on exposure to air. Most bag teas (although not all) contain leaves broken into small pieces; the great [[surface area to volume ratio]] of the leaves in tea bags exposes them to more air, and therefore causes them to go stale faster. Loose tea leaves are likely to be in larger pieces, or to be entirely intact.
* Breaking up the leaves for bags extracts flavored oils.
* The small size of the bag does not allow leaves to diffuse and steep properly.

The "pyramid tea bag" (or sachet) introduced by Lipton and PG Tips/Scottish Blend in 1996, attempts to address one of the connoisseurs' arguments against paper tea bags by way of its three-dimensional tetrahedron shape, which allows more room for tea leaves to expand while steeping. However, some types of pyramid tea bags have been criticized as being environmentally unfriendly, since their synthetic material is not as biodegradable as loose tea leaves and paper tea bags.

===Loose tea===
[[File:English Westminster Tea.jpg|thumb|A blend of loose-leaf black teas]]

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.

===Compressed tea===
Some teas (particularly [[Pu-erh tea]]) are still compressed for transport, storage, and aging convenience. The [[tea brick]] remains in use in the Himalayan countries or Mongolian steppes. The tea is prepared and steeped by first loosening leaves off the compressed cake using a small knife. Compressed teas can usually be stored for longer periods of time without spoilage when compared with loose leaf tea.

===Instant tea===
In recent times, "instant teas" are becoming popular, similar to freeze-dried instant coffee. Similar products also exist for instant iced tea, due to the convenience of not requiring boiling water. Instant tea was developed in the 1930s, but not commercialized until later. Nestea introduced the first instant tea in 1946, while Redi-Tea introduced the first instant iced tea in 1953.

These products often come with added flavors, such as chai, vanilla, honey or fruit, and may also contain powdered milk. Tea connoisseurs tend to criticize these products for sacrificing the delicacies of tea flavour in exchange for convenience.

===Bottled and canned tea===

Switzerland is considered as the motherland of bottled iced tea. Maks Sprengler, a Swiss businessman, tried the famous American iced tea and was the first to suggest producing ready-made iced tea in bottles. In 1983, Bischofszell Food Ltd. became the first producer in the world of  bottled ice tea on an industrial scale.

Canned tea is a form of tea that has already been prepared, and is sold ready to drink. Canned tea was first launched in 1981 in Japan. As such, it is a fairly recent innovation.

==Storage==
Tea shelf life varies with storage conditions and type of tea. Black tea has a longer shelf life than green tea. Some teas such as flower teas may go bad in a month or so. An exception, pu-erh tea, improves with age. Tea stays freshest when stored in a dry, cool, dark place in an air-tight container. Black tea stored in a bag inside a sealed opaque canister may keep for two years. Green tea loses its freshness more quickly, usually in less than a year. Gunpowder tea, its leaves being tightly rolled, keeps longer than the more open-leafed Chun Mee tea. Storage life for all teas can be extended by using desiccant packets, oxygen-absorbing packets, vacuum sealing or store tea in closed containers in a refrigerator.

When storing green tea, discreet use of refrigeration or freezing is recommended. In particular, drinkers need to take precautions against temperature variation.

Improperly stored tea may lose flavor, acquire disagreeable flavors or odors from other foods, or become moldy.

==Gallery==
<gallery>
Image:Da Hong Pao Oolong tea leaf close.jpg|[[Da Hong Pao tea]] an oolong tea
Image:Bai Hao Yin Zhen tea leaf (Fuding).jpg|Fuding [[Bai Hao Yinzhen tea]], a white tea
Image:Xiaguan Te Ji Tuo Cha 2004.jpg|Green pu-erh ''[[tuo cha]]'', a type of compressed raw pu-erh
Image:Huoshan_Huangya_tea_leaves_close.jpg|[[Huoshan Huangya tea]], a yellow tea
Image:Qi Lan Oolong tea leaf.jpg|Loose dried tea leaves
File:Oolong tea leaf.jpg|Taiwanese High Mountain oolong
</gallery>

==See also==

* [[Flowering tea]]
* [[Kombucha]], drink produced from bacteria and yeast grown on tea
* [[Tasseography]], a method of divination by reading tea leaves.
* [[Tea classics]], influential historical monographs of East Asian tea

===Bibliography===

*Claud Bald: Indian Tea. ''A Textbook on the Culture and Manufacture of Tea''. Fifth Edition. Thoroughly Revised and Partly Rewritten by C.J. Harrison. Thacker, Spink & Co., Calcutta 1940 (first edition, 1933).
* 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
*Harler, C.R., ''The Culture and Marketing of Tea''. Second edition. Oxford University Press, New York and Bombay, Reprinted 1958 (First edition 1933, second edition 1956).
*Eelco Hesse (1982), ''Tea: The eyelids of Bodhidharma'', Prism Press.
* 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
* Roy Moxham (2003), ''Tea: Addiction, Exploitation, and Empire''
* Victor H. Mair and Erling Hoh. ''The True History of Tea''. New York; London: Thames & Hudson,  2009.  ISBN 978-0-500-25146-1.
* Jane Pettigrew (2002), ''A Social History of Tea''
* Stephan Reimertz (1998): ''Vom Genuß des Tees: Eine heitere Reise durch alte Landschaften, ehrwürdige Traditionen und moderne Verhältnisse, inklusive einer kleinen Teeschule'' (In German)
* James Norwood Pratt (2005), ''Tea Dictionary''
* Lester Packer, Choon Nam Ong, Barry Halliwell (2004): ''Herbal and Traditional Medicine: Molecular Aspects of Health'', CRC Press, ISBN 0-8247-5436-0

[[Category:Tea]]

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