Tea

This article is about the beverage. For other uses, see Tea (disambiguation).
"Cup of tea" redirects here. For other uses, see Cup of Tea.
Tea

Tea leaves steeping in zhong caj

Oolong tea being infused in a gaiwan
Type Hot or cold beverage
Country of origin China[1]
Introduced First recorded in 59 BC, though probably originated earlier.[2]
Tea plant (Camellia sinensis) from Köhler's Medicinal Plants, 1897

Tea is an aromatic beverage commonly prepared by pouring hot or boiling water over cured leaves of the Camellia sinensis, an evergreen shrub native to Asia.[3] After water, it is the most widely consumed drink in the world.[4] There are many different types of tea; some teas, like Darjeeling and Chinese greens, have a cooling, slightly bitter, and astringent flavour,[5] while others have vastly different profiles that include sweet, nutty, floral or grassy notes.

Tea originated in southwestern China, where it was used as a medicinal drink.[6] It was popularized as a recreational drink during the Chinese Tang dynasty, and tea drinking spread to other East Asian countries. Portuguese priests and merchants introduced it to the West during the 16th century.[7] During the 17th century, drinking tea became fashionable among Britons, who started large-scale production and commercialization of the plant in India to bypass a Chinese monopoly at that time.[8]

The phrase herbal tea usually refers to infusions of fruit or herbs made without the tea plant, such as steeps of rosehip, chamomile, or rooibos. These are also known as tisanes or herbal infusions to distinguish them from "tea" as it is commonly construed.

Etymology

Main article: Etymology of tea
1885 illustration of Xiamen (Amoy) by Edwin Joshua Dukes

The Chinese character for tea is 茶, originally written with an extra stroke as 荼 (pronounced tú, used as a word for a bitter herb), and acquired its current form during the Tang Dynasty.[9][10][11] The word is pronounced differently in the different varieties of Chinese, such as chá in Mandarin, zo and dzo in Wu Chinese, and ta and te in Min Chinese.[12] One suggestion is that the different pronunciations may have arisen from the different words for tea in ancient China, for example tú (荼) may have given rise to tê;[13] historical phonologists however argued that the cha, te and dzo all arose from the same root with a reconstructed pronunciation dra, which changed due to sound shift through the centuries.[14] There were other ancient words for tea, though ming (茗) is the only other one still in common use.[14][15] It has been proposed that the Chinese words for tea, tu, cha and ming, may have been borrowed from the Austro-Asiatic languages of people who inhabited southwest China; cha for example may have been derived from an archaic Austro-Asiatic root *la, meaning "leaf".[16]

Most Chinese languages, such as Mandarin and Cantonese, pronounce it along the lines of cha, but Hokkien varieties along the Southern coast of China and in Southeast Asia pronounce it like teh. These two pronunciations have made their separate ways into other languages around the world.[17] Te is from the Amoy tê of southern Fujian province. 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. This pronunciation gives rise to English "tea" and other similar words in other languages such as Spanish "té", French "thé", German "Tee", and Dutch "thee", and is the most common form worldwide.[18] Cha is from the Cantonese chàh of 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 pronunciations of cha, however, came not from Cantonese, rather they were borrowed into Korean and Japanese during earlier periods of Chinese history. Due to the Portuguese occupation of Macau, the Portuguese adopted the Cantonese pronunciation "chá", instead of the more typical Western pronunciations deriving from tê.

A third form, the increasingly widespread chai came from Persian چای chay. Both the châ and chây forms are found in Persian dictionaries.[19] They are derived from the Northern Chinese pronunciation of chá,[20] which passed overland to Central Asia and Persia, where it picked up the Persian grammatical suffix -yi before passing on to Russian as чай (chay), Arabic as شاي (pronounced shay due to the lack of a "ch" sound in Arabic), Urdu as چائے chay, Hindi as चाय chāy, Turkish as çay, etc.[21] The few exceptions of words for tea that do not fall into the three broad groups of te, cha and chai are mostly from the minor languages from the botanical homeland of the tea plant from which the Chinese words for tea might have been borrowed originally.[14] English has all three forms: cha or char (both pronounced /ˈtʃɑː/), attested from the 16th century; tea, from the 17th; and chai, from the 20th. However, the form chai refers specifically to a black tea mixed with honey, spices and milk in contemporary English. [22]

Origin and history

Further information: History of tea
A 19th-century Japanese painting depicting Shennong: Chinese legends credit Shennong with the invention of tea.[23]

Tea plants are native to East Asia, and probably originated around the meeting points of the lands of north Burma and southwest China.[24] Statistical cluster analysis, chromosome number, easy hybridization, and various types of intermediate hybrids and spontaneous polyploids indicate that likely a single place of origin exists for Camellia sinensis, an area including the northern part of Burma, and Yunnan and Sichuan provinces of China.[24] Tea drinking may have begun in the Yunnan region during the Shang Dynasty in China, when it was used for medicinal purposes.[6] It is also believed that in Sichuan, "people began to boil tea leaves for consumption into a concentrated liquid without the addition of other leaves or herbs, thereby using tea as a bitter yet stimulating drink, rather than as a medicinal concoction."[6]

Chinese legends attribute the invention of tea to Shennong in 2737 BC,[23] although evidence suggests that tea drinking may have been introduced from the southwest of China (Sichuan/Yunnan area). The earliest written records of tea come from China. In 2016, the discovery of the earliest known physical evidence of tea from the mausoleum of Emperor Jing of Han in Xi'an was reported, indicating that tea from the genus Camellia was drunk by Han Dynasty emperors as early as 2nd century BC.[25] The word tú 荼 appears in the Shijing and other ancient texts to signify a kind of "bitter vegetable" (苦菜), and it is possible that it referred to a number of different plants such as sowthistle, chicory, or smartweed,[26] as well as tea.[14] In the Chronicles of Huayang, it was recorded that the Ba people in Sichuan presented tu to the Zhou king. The state of Ba and its neighbour Shu were later conquered by the Qin, and according to the 17th century scholar Gu Yanwu who wrote in Ri Zhi Lu (日知錄): "It was after the Qin had taken Shu that they learned how to drink tea."[2] The Han dynasty work "The Contract for a Youth", written by Wang Bao in 59 BC, contains the first known reference to boiling tea. Among the tasks listed to be undertaken by the youth, the contract states that "he shall boil tea and fill the utensils" and "he shall buy tea at Wuyang".[2] The first record of tea cultivation is also dated to this period (the reign of Emperor Xuan of Han), during which tea was cultivated on Meng Mountain (蒙山) near Chengdu.[27]

An early credible record of tea drinking dates to the third century AD, in a medical text by Hua Tuo, who stated, "to drink bitter t'u constantly makes one think better."[28] Another possible early reference to tea is found in a letter written by the Qin Dynasty general Liu Kun. However, before the mid-8th century Tang dynasty, tea-drinking was primarily a southern Chinese practice.[29] It became widely popular during the Tang Dynasty, when it was spread to Korea, Japan, and Vietnam. In India, tea has been drunk for medicinal purposes for a long but uncertain period, but apart from the Himalayan region it seems not to have been used as a beverage until the British introduced tea-drinking there much later.

Through the centuries, a variety of techniques for processing tea, and a number of different forms of tea, were developed. During the Tang dynasty, tea was steamed, then pounded and shaped into cake form,[30] while in the Song dynasty, loose-leaf tea was developed and became popular. During the Yuan and Ming dynasties, unoxidized tea leaves were first pan-fried, then rolled and dried, a process that stops the oxidation process which turns the leaves dark and allows tea to remain green. In the 15th century, oolong tea, in which the leaves were allowed to partially oxidize before pan-frying, was developed.[31] Western tastes, however, favoured the fully oxidized black tea, and the leaves were allowed to oxidize further. Yellow tea was an accidental discovery in the production of green tea during the Ming dynasty, when apparently sloppy practices allowed the leaves to turn yellow, but yielded a different flavour as a result.[32]

Tea-weighing station north of Batumi, Russian Empire before 1915

Tea was first introduced to Portuguese priests and merchants in China during the 16th century, at which time it was termed chá.[7] The earliest European reference to tea, written as Chiai, came from Delle navigationi e viaggi written by a Venetian, Giambattista Ramusio, in 1545.[33] The first recorded shipment of tea by a European nation was in 1607 when the Dutch East India Company moved a cargo of tea from Macao to Java, then two years later, the Dutch bought the first assignment of tea which was from Hirado in Japan to be shipped to Europe.[34] Tea became a fashionable drink in The Hague in the Netherlands, and the Dutch introduced the drink to Germany, France and across the Atlantic to New Amsterdam (New York).[35]

The first record of tea in English came from a letter written by Richard Wickham, who ran an East India Company office in Japan, writing to a merchant in Macao requesting "the best sort of chaw" in 1615. Peter Mundy, a traveller and merchant who came across tea in Fujian in 1637, wrote, "chaa — only water with a kind of herb boyled in it ".[36][37] Tea was sold in a coffee house in London in 1657, Samuel Pepys tasted tea in 1660, and Catherine of Braganza took the tea-drinking habit to the British court when she married Charles II in 1662. Tea, however, was not widely consumed in Britain until the 18th century, and remained expensive until the latter part of that period. British drinkers preferred to add sugar and milk to black tea, and black tea overtook green tea in popularity in the 1720s.[38] Tea smuggling during the 18th century led to the general public being able to afford and consume tea. The British government removed the tax on tea, thereby eliminating the smuggling trade by 1785.[39] In Britain and Ireland, tea was initially consumed as a luxury item on special occasions, such as religious festivals, wakes, and domestic work gatherings. The price of tea in Europe fell steadily during the 19th century, especially after Indian tea began to arrive in large quantities; by the late 19th century tea had become an everyday beverage for all levels of society.[40] The popularity of tea also informed a number of historical events – the Tea Act of 1773 provoked the Boston Tea Party that escalated into the American Revolution, and the need to address the issue of British trade deficit caused by the demand for Chinese tea eventually resulted in the Opium Wars.

Tea was introduced into India by the British in an attempt to break the Chinese monopoly on tea.[41] In 1841, Arthur Campbell brought seeds of Chinese tea from the Kumaun region and experimented with planting tea in Darjeeling. The Alubari tea garden was opened in 1856 and Darjeeling tea began to be produced.[42] In 1848, 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 Anglo-Chinese First Opium War (1839–1842) and Second Opium War (1856–1860).[43] The Chinese tea plants he brought back were introduced to the Himalayas, though most did not survive. The British had discovered that a different variety of tea was endemic to Assam and the northeast region of India and that it was used by the local Singpho people, and these were then grown instead of the Chinese tea plant. Using the Chinese planting and cultivation techniques, the British launched a tea industry by offering land in Assam to any European who agreed to cultivate it for export.[41] Tea was originally consumed only by anglicized Indians; however, it became widely popular in India in the 1950s because of a successful advertising campaign by the India Tea Board.[41]

Cultivation and harvesting

Tea plantation workers in Sri Lanka, 2009

Camellia sinensis is an evergreen plant that grows mainly in tropical and subtropical climates.[44] Some varieties can also tolerate marine climates and are cultivated as far north as Cornwall in the United Kingdom,[45] Perthshire in Scotland,[46][47][48] Washington state in the United States,[49] Vancouver Island in Canada,.[50] In the Southern Hemisphere, tea is grown as far south as Hobart on the Australian island of Tasmania[51][52] and Waikato in New Zealand.[53]

Tea plants are propagated from seed and cuttings; about 4 to 12 years are needed for a plant to bear seed and about three years before a new plant is ready for harvesting.[44] In addition to a zone 8 climate or warmer, tea plants require at least 127 cm (50 in) of rainfall a year and prefer acidic soils.[54] Many high-quality tea plants are cultivated at elevations of up to 1,500 m (4,900 ft) above sea level. Though at these heights the plants grow more slowly, they acquire a better flavour.[55]

Two principal varieties are used: Camellia sinensis var. sinensis, which is used for most Chinese, Formosan and Japanese teas, and C. s. var. assamica, used in Pu-erh and most Indian teas (but not Darjeeling). Within these botanical varieties, many strains and modern clonal varieties are known. Leaf size is the chief criterion for the classification of tea plants, with three primary classifications being,[56] Assam type, characterised by the largest leaves; China type, characterised by the smallest leaves; and Cambodian type, characterised by leaves of intermediate size.

A tea plant will grow into a tree of up to 16 m (52 ft) if left undisturbed,[44] but cultivated plants are generally pruned to waist height for ease of plucking. Also, the short plants bear more new shoots which provide new and tender leaves and increase the quality of the tea.[57]

Only the top 1–2 inches of the mature plant are picked. These buds and leaves are called 'flushes'.[58] A plant will grow a new flush every seven to 15 days during the growing season. Leaves that are slow in development tend to produce better-flavoured teas.[44] Pests of tea include mosquito bugs of the genus Helopeltis (which are true bugs that must not be confused with the dipteran) that can tatter leaves, so they may be sprayed with insecticides.

Chemical composition

Caffeine constitutes about 3% of tea's dry weight, translating to between 30 mg and 90 mg per 8-oz (250-ml) cup depending on type, brand,[59] and brewing method.[60] A study found that the caffeine content of 1 g of black tea ranged from 22 to 28 mg, while the caffeine content of 1 g of green tea ranged from 11 to 20 mg, reflecting a significant difference.[61]

Tea also contains small amounts of theobromine and theophylline, which are stimulants and xanthines similar to caffeine.[62]

Because of modern environmental pollution, fluoride and aluminium also sometimes occur in tea. Certain types of brick tea made from old leaves and stems have the highest levels.[63][64]

Black and green teas contain no essential nutrients in significant content, with the exception of the dietary mineral, manganese at 0.5 mg per cup or 26% of the Daily Value.[65] Tea leaves contain diverse polyphenols, including flavonoids, epigallocatechin gallate (commonly noted as EGCG) and other catechins.[66][67]

It has been suggested that green and black tea may protect against cancer[68] or other diseases such as obesity[69] or Alzheimer's disease,[70] but the compounds found in green tea have not been conclusively demonstrated to have any effect on human diseases.[71][72] One human study demonstrated that regular consumption of black tea over four weeks had no beneficial effect in lowering blood cholesterol levels.[73]

Processing and classification

Main article: Tea processing
Common processing methods of tea leaves
Fresh tea leaves in various stages of growth; the smaller the leaf, the more expensive the tea

Tea is generally divided into categories based on how it is processed.[74] At least six different types are produced:

The most common are white, green, oolong, and black.

After picking, the leaves of C. sinensis soon begin to wilt and oxidize unless immediately dried. An enzymatic oxidation process triggered by the plant's intracellular enzymes causes the leaves to turn progressively darker as their chlorophyll breaks down and tannins are released. This darkening is stopped at a predetermined stage by heating, which deactivates the enzymes responsible. In the production of black teas, halting by heating is carried out simultaneously with drying. Without careful moisture and temperature control during manufacture and packaging, growth of undesired molds and bacteria may make tea unfit for consumption.

Although single-estate teas are available, almost all tea in bags and most loose tea sold in the West is blended. Such teas may combine others from the same cultivation area or several different ones. The aim is to obtain consistency, better taste, higher price, or some combination of the three.

Tea easily retains odors, which can cause problems in processing, transportation, and storage. This same sensitivity also allows for special processing (such as tea infused with smoke during drying) and a wide range of scented and flavoured variants, such as bergamot (found in Earl Grey), vanilla, and spearmint.

Additions

Further information: Tea blending and additives
Black tea is often taken with milk

Tea is often drunk with additions to the basic tea leaf and water. These can be grouped into flavourings added to the tea in processing before sale and those added during preparation or drinking. The former are often floral, herbal or spice flavourings and the latter include milk, sugar, lemon, among other things.

Milk

The addition of milk to tea in Europe was first mentioned in 1680 by the epistolist Madame de Sévigné.[75] 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 neutralise remaining tannins and reduce acidity.[76][77] The Han Chinese do not usually drink milk with tea 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. In Australia, tea with milk is white tea.

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.[78] Others insist it is better to add the milk after brewing the tea, as black tea is often 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 flavour 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 colour 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.[79] Higher temperature difference means faster heat transfer so the earlier you add milk the slower the drink cools. A 2007 study published in the European Heart Journal found certain beneficial effects of tea may be lost through the addition of milk.[80]

Others

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. 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 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, a butter made from yak milk, which is churned vigorously in a cylindrical vessel closely resembling a butter churn. The same may be said for salt tea, which is popular in the Hindu Kush region of northern Pakistan.

Pouring from height

The flavour 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, Libya and Western Sahara), but also in West Africa (e.g. Guinea, Mali, Senegal) and can positively alter the flavour 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 oxidisation 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 Singapore and 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" (which has its origin as a hot Indian tea beverage), 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.

Preparation

Teas of different levels of oxidation (L to R): green, yellow, oolong, and black

Black tea

Popular varieties of black tea include Assam, Nepal, Darjeeling, Nilgiri, Turkish, Keemun, and Ceylon teas.

Many of the active substances in black tea do not develop at temperatures lower than 90 °C (194 °F).[81] As a result, black tea in the West is usually steeped in water near its boiling point, at around 99 °C (210 °F). 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. Warming the tea pot before steeping is critical at any elevation.

Western 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, actively boiling water is used and the tea is often stewed. In India, black tea is often boiled for fifteen minutes or longer to make Masala chai, as a strong brew is preferred. Tea should be strained while serving.

A food safety management group of the International Organization for Standardization (ISO) has published a standard for preparing a cup of tea (ISO 3103: Tea — Preparation of liquor for use in sensory tests), primarily intended for standardizing preparation for comparison and rating purposes.

Green tea

In regions of the world that prefer mild beverages, such as the West and Far East, green tea should be steeped in water around 80 to 85 °C (176 to 185 °F), the higher the quality of the leaves the lower the temperature. Regions such as North Africa or Central Asia prefer a bitter tea, and hotter water is used. In Morocco, green tea is steeped in boiling water for 15 minutes.

The container in which green tea is steeped is often warmed beforehand to prevent premature cooling. 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.

Flowering tea

Flowering tea or blooming tea should be brewed at 100 °C (212 °F) in clear glass tea wares for up to three minutes. First pull 1/3 water to make the tea ball wet and after 30 seconds add the boiling water up to 4/5 of the capacity of the tea ware. The boiling water can help the tea ball bloom quickly and with a strong aroma of the tea. The height of glass tea ware should be 8–10 cm, which can help the tea and flowers bloom completely. One tea ball can be brewed 4–5 times.

Oolong tea

Oolong tea should be brewed around 82 to 96 °C (185 to 205 °F), with the brewing vessel warmed before pouring the water. Yixing purple clay teapots are the traditional brewing-vessel for oolong tea which can be brewed multiple times from the same leaves, unlike green tea, seeming to improve with reuse. In the Chinese and Taiwanese Gongfu tea ceremony, the first brew is discarded, as it is considered a rinse of leaves rather than a proper brew.

Premium or delicate tea

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 ageing process, then infuse it at the boiling point (100 °C or 212 °F), and allow it to steep from 30 seconds to five minutes.

Cold brew and sun tea

See also: Cold brew tea and Iced tea

While most tea is prepared using hot water, it is also possible to brew a beverage from tea using room temperature or cooled water. This requires longer steeping time to extract the key components, and produces a different flavor profile. For best results, it is best to use about 1.5 times the tea leaves that would be used for hot steeping, and to refrigerate for 4–10 hours. The process of making cold brew tea is much simpler than that for cold brew coffee.

Cold brewing has some disadvantages compared to hot steeping. Firstly, if the leaves or source water contain unwanted bacteria, they may flourish, whereas using hot water has the benefit of killing most bacteria. This is less of a concern in modern times and developed regions. Secondly, cold brewing may allow for less caffeine to be extracted, which may or may not be desired.

Sun Tea is made by steeping the tea leaves in a jar of unheated tap water left in the sun. It does not get hot enough to kill bacteria present on the tea leaves or in the water, such as Alcaligenes viscolactis.[82]

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.

Tea culture

Main article: Tea culture
Masala chai from India with garnishes
Turkish tea served in typical small glass and corresponding plate
Iced tea with a slice of lemon

Tea may be consumed early in the day to heighten calm alertness; it contains L-theanine, theophylline, and bound caffeine[5] (sometimes called theine). Decaffeinated brands are also sold. While herbal teas are also referred to as tea, most of them do not contain leaves from the tea plant.

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 ceremonies have arisen in different cultures, such as the Chinese and Japanese tea ceremonies, each of which employs traditional techniques and ritualised 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 teapots and oolong tea.

Turkish tea is an important part of Turkish cuisine, and is the most commonly consumed hot drink, despite the country's long history of coffee consumption. In 2004 Turkey produced 205,500 tonnes of tea (6.4% of the world's total tea production), which made it one of the largest tea markets in the world,[83] with 120,000 tons being consumed in Turkey, and the rest being exported.[84] In 2010 Turkey had the highest per capita consumption in the world at 2.7 kg.[85] As of 2013, the per-capita consumption of Turkish tea exceeds 10 cups per day and 13.8 kg per year.[86] Tea is grown mostly in Rize Province on the Black Sea coast.[87]

In the United Kingdom, 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 for a host to offer tea to guests soon after their arrival. Tea is consumed both at home and outside the home, often in cafés. Afternoon tea with cakes on fine porcelain is a cultural stereotype, sometimes available in quaint tea-houses. In southwest England, many cafés serve a 'cream tea', consisting of scones, clotted cream, and jam alongside a pot of tea. Throughout the UK, 'tea' may also refer to the evening meal.

Ireland has long 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 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.

Russia has a long, rich tea history dating to 1638 when tea was introduced to Tsar Michael I of Russia. Social gatherings were considered incomplete without tea, which was traditionally brewed in a samovar, and today 82% of Russians consume tea daily.

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

In Pakistan, tea is called chai (written as چائے). 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 transnational Kashmir region, which straddles the border between India and Pakistan, Kashmiri chai or noon chai, a pink, creamy tea with pistachios, almonds, cardamom, and sometimes cinnamon, is consumed primarily at special occasions, weddings, and during the winter months when it is sold in many kiosks.

In central and southern Punjab and the metropolitan Sindh region of Pakistan, tea with milk and sugar (sometimes with pistachios, cardamom, etc.), commonly referred to as chai, is widely consumed. It is the most common beverage of households in the region. 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.[88]

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 21 April 2012, the Deputy Chairman of Planning Commission (India), Montek Singh Ahluwalia, said tea would be declared as national drink by April 2013.[89][90] 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.[91]

In the United States, 80% of tea is consumed as iced tea.[92] Sweet tea is native to the southeastern US, and is iconic in its cuisine.

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.

Economics

Tea factory in Taiwan

Tea is the most popular manufactured drink consumed in the world, equaling all others – including coffee, chocolate, soft drinks, and alcohol – combined.[4] 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,[93] although the per capita consumption of tea remains a modest 750 grams per person every year. Turkey, with 2.5 kg of tea consumed per person per year, is the world's greatest per capita consumer.[94]

Production

In 2003, world tea production was 3.21 million tonnes annually.[95] In 2010, world tea production reached over 4.52 million tonnes after having increased by 5.7% between 2009 and 2010.[96] Production rose by 3.1% between 2010. In 2013, world tea production reached over 5.34 million tonnes after having increased by 6.17% between 2012 and 2013 . The largest producers of tea are the People's Republic of China, India, Kenya, Sri Lanka, and Turkey.

Percentage of total tea production in 2008
   Less than 0.5% or insignificant quantities
   From 0.5 to 1%.
   From 1 to 5%.
   From 5 to 10%.
   From 10 to 20%.
   More than 20%
Percentage of total global tea production by country in 2013

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 2014.[95]

RankCountry[95] 2008200920102011 2012 2013
1  China1,257,6001,359,0001,450,0001,623,0001,804,6551,939,457
2  India987,000972,700991,1801,063,5001,135,0701,208,780
3  Kenya345,800314,100399,000377,912369,400432,400
4  Sri Lanka318,700290,000282,300327,500330,000340,230
5  Vietnam173,500185,700198,466206,600216,900214,300
6 Turkey198,046198,601235,000221,600225,000212,400
7  Iran165,717165,717165,717162,517158,000160,000
8  Indonesia150,851146,440150,000142,400143,400148,100
9  Argentina80,14271,71588,57496,57282,813105,000
10  Japan96,50086,00085,00082,10085,90084,800
TotalWorld4,211,3974,242,2804,518,0604,321,0115,034,9685,345,523

Labor and consumer safety problems

Multiple recent reports have found that most Chinese and Indian teas contain residues of banned toxic pesticides.[97][98][99][100]

Tea production in Kenya, Malawi, Rwanda, Tanzania, and Uganda has been reported to make use of child labor according to the U.S. Department of Labor's List of Goods Produced by Child Labor or Forced Labor[101] (a report on the worst forms of child labor).

Certification

Workers who pick and pack tea on plantations in developing countries can face harsh working conditions and may earn below the living wage.[102]

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, which also certify other crops such as coffee, cocoa and fruit. 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 has risen since its introduction in 1990 at Rembeng, Kondoli Tea Estate, Assam.[103] 6,000 tons of organic tea were sold in 1999.[104] About 75% of organic tea production 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.[105] Kenya, China, India and Sri Lanka were the largest exporters of tea in 2007 (with exports of: 374229, 292199, 193459 and 190203 tonnes respectively).[105][106] The largest exporter of black tea is Kenya, with the largest producer, (and consumer) being India.[106][107]

Packaging

Tea bags

Tea bags
Main article: Tea bag

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 realised until later on. During World War II, tea was rationed in the United Kingdom. In 1953 (after rationing in the UK ended), Tetley launched the tea bag to the UK and it was an immediate success.

The "pyramid tea bag" (or sachet) introduced by Lipton[108] and PG Tips/Scottish Blend in 1996,[109] 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 criticised as being environmentally unfriendly, since their synthetic material is not as biodegradable as loose tea leaves and paper tea bags.[110]

Loose tea

A blend of loose-leaf black teas

The tea leaves are packaged loosely in a canister, paper bag, or other container such as a tea chest. Some whole teas, such as rolled gunpowder tea leaves, which resist crumbling, are sometimes vacuum packed for freshness in aluminised packaging for storage and retail. The loose tea must be individually measured for use, allowing for flexibility and flavor control at the expense of convenience. Strainers, tea balls, tea presses, filtered teapots, and infusion bags prevent loose leaves from floating in the tea and over-brewing. A traditional method uses a three-piece lidded teacup called a gaiwan, the lid of which is tilted to decant the tea into a different cup for consumption.

Compressed tea

Compressed tea (such as Pu-erh) is produced for convenience in transport, storage, and ageing. It can usually be stored longer without spoilage than loose leaf tea.

Compressed tea is prepared by loosening leaves from the cake using a small knife, and steeping the extracted pieces in water. During the Tang dynasty, as described by Lu Yu, compressed tea was ground into a powder, combined with hot water, and ladled into bowls, resulting in a "frothy" mixture.[111] In the Song dynasty, the tea powder would instead be whisked with hot water in the bowl. Although no longer practiced in China today, the whisking method of preparing powdered tea was transmitted to Japan by Zen Buddhist monks, and is still used to prepare matcha in the Japanese tea ceremony.[112]

Compressed tea was the most popular form of tea in China during the Tang dynasty.[113] By the beginning of the Ming dynasty, it had been displaced by loose leaf tea.[114] It remains popular, however, in the Himalayan countries and Mongolian steppes. In Mongolia, tea bricks were ubiquitous enough to be used as a form of currency. Among Himalayan peoples, compressed tea is consumed by combining it with yak butter and salt to produce butter tea.[115]

Instant tea

"Instant tea", similar to freeze-dried instant coffee and an alternative to brewed tea, can be consumed either hot or cold. Instant tea was developed in the 1930s, with Nestlé introducing the first commercial product in 1946, while Redi-Tea debuted instant iced tea in 1953.

Delicacy of flavour is sacrificed for convenience. Additives such as chai, vanilla, honey or fruit, are popular, as is powdered milk.

During the Second World War British and Canadian soldiers were issued an instant tea known as 'Compo' in their Composite Ration Packs. These blocks of instant tea, powdered milk, and sugar were not always well received. As Royal Canadian Artillery Gunner, George C Blackburn observed:

But, unquestionably, the feature of Compo rations destined to be remembered beyond all others is Compo tea...Directions say to "sprinkle powder on heated water and bring to the boil, stirring well, three heaped teaspoons to one pint of water."

Every possible variation in the preparation of this tea was tried, but...it always ended up the same way. While still too hot to drink, it is a good-looking cup of strong tea. Even when it becomes just cool enough to be sipped gingerly, it is still a good-tasting cup of tea, if you like your tea strong and sweet. But let it cool enough to be quaffed and enjoyed, and your lips will be coated with a sticky scum that forms across the surface, which if left undisturbed will become a leathery membrane that can be wound around your finger and flipped away...[116]

Bottled and canned tea

Main article: Canned tea

Canned tea is sold prepared and ready to drink. It was introduced in 1981 in Japan.

The first bottled tea introduced by Indonesian tea company PT. Sinar Sosro in 1969 with brand name Teh Botol Sosro (or Sosro bottled tea).[117]

In 1983, Swiss-based Bischofszell Food Ltd., was the first company to bottle ice tea on an industrial scale.[118]

Storage

Storage conditions and type determine the shelf life of tea. Black tea's is greater than green's. Some, such as flower teas, may last only a month or so. Others, such as pu-erh, improve with age.

To remain fresh and prevent mold, tea needs to be stored away from heat, light, air, and moisture. Tea must be kept at room temperature in an air-tight container. Black tea in a bag within a sealed opaque canister may keep for two years. Green tea deteriorates more rapidly, usually in less than a year. Tightly rolled gunpowder tea leaves keep longer than the more open-leafed Chun Mee tea.

Storage life for all teas can be extended by using desiccant or oxygen-absorbing packets, vacuum sealing, or refrigeration in air-tight containers (except green tea, where discrete use of refrigeration or freezing is recommended and temperature variation kept to a minimum).[119]


Gallery

See also

References

  1. ↑ Fuller, Thomas (21 April 2008). "A Tea From the Jungle Enriches a Placid Village". The New York Times (New York). p. A8.
  2. 1 2 3 Mair & Hoh 2009, pp. 29–30.
  3. ↑ Martin, p. 8
  4. 1 2 Alan Macfarlane; Iris Macfarlane (2004). The Empire of Tea. The Overlook Press. p. 32. ISBN 1-58567-493-1.
  5. 1 2 Penelope Ody, (2000). Complete Guide to Medicinal Herbs. New York, NY: Dorling Kindersley Publishing. p. 48. ISBN 0-7894-6785-2.
  6. 1 2 3 Mary Lou Heiss; Robert J. Heiss (23 March 2011). The Story of Tea: A Cultural History and Drinking Guide. Random House. p. 31. ISBN 978-1-60774-172-5. By the time of the Shang dynasty (1766–1050 BC), tea was being consumed in Yunnan Province for its medicinal properties
  7. 1 2 Bennett Alan Weinberg; Bonnie K. Bealer (2001). The World of Caffeine: The Science and Culture of the World's Most Popular Drug. Psychology Press. p. 63. ISBN 978-0-415-92722-2.
  8. ↑ http://www.teamuse.com/article_000803.html
  9. ↑ Albert E. Dien (2007). Six Dynasties Civilization. Yale University Press. p. 362. ISBN 978-0-300-07404-8.
  10. ↑ Bret Hinsch (2011). The ultimate guide to Chinese tea. ISBN 9789744801296.
  11. ↑ Nicola Salter (2013). Hot Water for Tea. ArchwayPublishing. p. 4. ISBN 978-1-60693-247-6.
  12. ↑ Peter T. Daniels, ed. (1996). The World's Writing Systems. Oxford University Press. p. 203. ISBN 978-0-19-507993-7.
  13. ↑ Keekok Lee (2008). Warp and Weft, Chinese Language and Culture. Eloquent Books. p. 97. ISBN 978-1-60693-247-6.
  14. 1 2 3 4 Mair & Hoh 2009, pp. 264–265.
  15. ↑ "Why we call tea "cha" and "te"?", Hong Kong Museum of Tea Ware
  16. ↑ Mair & Hoh 2009, pp. 265–267.
  17. ↑ Dahl, Östen. "Feature/Chapter 138: Tea". The World Atlas of Language Structures Online. Max Planck Digital Library. Retrieved 4 June 2008.
  18. ↑ Mair & Hoh 2009, pp. 262.
  19. ↑ Mair & Hoh 2009, p. 263.
  20. ↑ "Chai". American Heritage Dictionary. Chai: A beverage made from spiced black tea, honey, and milk. ETYMOLOGY: Ultimately from Chinese (Mandarin) chá.
  21. ↑ "tea". Online Etymology Dictionary. The Portuguese word (attested from 1550s) came via Macao; and Rus. chai, Pers. cha, Gk. tsai, Arabic shay, and Turk. çay all came overland from the Mandarin form.
  22. ↑ "Definition of CHAI". www.merriam-webster.com. Retrieved 2016-04-07.
  23. 1 2 Yee, L. K., Tea’s Wonderful History, The Chinese Historical and Cultural Project, archived from the original on 13 August 2002, retrieved 17 June 2013, year 1996–2012
  24. 1 2 Yamamoto, T; Kim, M; Juneja, L R (1997). Chemistry and Applications of Green Tea. CRC Press. p. 4. ISBN 0-8493-4006-3. For a long time, botanists have asserted the dualism of tea origin from their observations that there exist distinct differences in the morphological characteristics between Assamese varieties and Chinese varieties... Hashimoto and Shimura reported that the differences in the morphological characteristics in tea plants are not necessarily the evidence of the dualism hypothesis from the researches using the statistical cluster analysis method. In recent investigations, it has also been made clear that both varieties have the same chromosome number (n=15) and can be easily hybridised with each other. In addition, various types of intermediate hybrids or spontaneous polyploids of tea plants have been found in a wide area extending over the regions mentioned above. These facts may prove that the place of origin of Camellia sinensis is in the area including the northern part of the Burma, Yunnan, and Sichuan districts of China.
  25. ↑ Houyuan Lu et al. (7 January 2016). "Earliest tea as evidence for one branch of the Silk Road across the Tibetan Plateau". Nature. doi:10.1038/srep18955. Retrieved 11 January 2016.
  26. ↑ James A. Benn (2015-04-23). Tea in China: A Religious and Cultural History. Hong Kong University Press. p. 22. ISBN 9789888208739.
  27. ↑ Mair & Hoh 2009, pp. 30–31.
  28. ↑ Bennett Alan Weinberg, Bonnie K. Bealer (2001). The World of Caffeine: The Science and Culture of the World's Most Popular Drug. Routledge. p. 28. ISBN 978-0415927222.
  29. ↑ James A. Benn (2015-04-23). Tea in China: A Religious and Cultural History. Hong Kong University Press. p. 42. ISBN 9789888208739.
  30. ↑ Mair & Hoh 2009, pp. 39–41.
  31. ↑ James A. Benn (2015-04-23). Tea in China: A Religious and Cultural History. Hong Kong University Press. p. 42. ISBN 9789888208739.
  32. ↑ Mair & Hoh 2009, p. 118.
  33. ↑ Mair & Hoh 2009, p. 165.
  34. ↑ Mair & Hoh 2009, p. 106.
  35. ↑ Mair & Hoh 2009, p. 169.
  36. ↑ Paul Chrystal (October 17, 2014). Tea: A Very British Beverage. Amberley Publishing Limited.
  37. ↑ Peter Mundy Merchant Adventurer, 2011, ed. R E Pritchard, Bodleain Library, Oxford
  38. ↑ "Tea". In Our Time. 29 April 2004. BBC Radio 4.
  39. ↑ "A Social History of the Nation's Favourite Drink". United Kingdom Tea Council. Archived from the original on 30 July 2009.
  40. ↑ Lysaght, Patricia (1987). "When I makes Tea, I makes Tea: the case of Tea in Ireland". Ulster Folklife 33: 48–49.
  41. 1 2 3 Colleen Taylor Sen (2004). Food Culture in India. Greenwood Publishing Group. p. 26. ISBN 978-0-313-32487-1. Ironically, it was the British who introduced tea drinking to India, initially to anglicized Indians. Tea did not become a mass drink there until the 1950s when the India Tea Board, faced with a surplus of low-grade tea, launched an advertising campaign to popularize it in the north, where the drink of choice was milk.
  42. ↑ Mair & Hoh 2009, p. 214.
  43. ↑ Sarah Rose (2010). For All the Tea in China: How England Stole the World's Favorite Drink and Changed History. Penguin Books. pp. 1–5, 89, 122, 197.
  44. 1 2 3 4 "Camellia Sinensis". Purdue University Center for New Crops and Plants Products. 3 July 1996. Retrieved 26 October 2010.
  45. ↑ Levin, Angela (20 May 2013). "Welcome to Tregothnan, England's only tea estate". The Telegraph. Retrieved 5 December 2013.
  46. ↑ Hilpern, Kate (17 November 2014). "The world's first Scottish tea (at £10 a cup)". The Independent.
  47. ↑ Winter, Katy (17 April 2014). "For all the tea in.... Scotland? Leaf experts behind a plantation in the Highlands say they've come up with the PERFECT brew". Daily Mail.
  48. ↑ "Wee Tea Company brewing success at Perthshire plantation". BBC News. 9 April 2014.
  49. ↑ "Tea" (PDF). The Compendium of Washington Agriculture. Washington State Commission on Pesticide Registration. 2010. Retrieved 26 April 2011.
  50. ↑ "Tea farm on Vancouver Island, a Canadian first". Vancouver Sun. 5 May 2013. Retrieved 26 May 2014.
  51. ↑ Crawley, Jennifer (13 August 2013). "Tassie tea crop brewing". The Mercury (Hobart). Archived from the original on 2014-03-11.
  52. ↑ "Episode 36 – Produce of Two Islands". The Cook and the Chef. Episode 36. 29 October 2008. ABC Australia.
  53. ↑ "Tea growing is tough going". New Zealand Herald. 17 August 2013.
  54. ↑ Rolfe, Jim & Cave, Yvonne (2003). Camellias: A Practical Gardening Guide. Timber Press. ISBN 0-88192-577-2.
  55. ↑ Pruess, Joanna (2006). Tea Cuisine: A New Approach to Flavoring Contemporary and Traditional Dishes. Globe Pequot. ISBN 1-59228-741-7.
  56. ↑ Mondal, T.K. (2007). "Tea". In Pua, E.C.; Davey, M.R. Biotechnology in Agriculture and Forestry. 60: Transgenic Crops V. Berlin: Springer. pp. 519–520. ISBN 3-540-49160-0.
  57. ↑ Harler, Campbell Ronald (2014-08-26). "Tea production". Encyclopædia Britannica. Retrieved June 2007.
  58. ↑ Hayes, Elizabeth S. (1980). Spices and Herbs: Lore and Cookery. Courier Dover Publications. p. 74. ISBN 0-486-24026-6.
  59. ↑ Weinberg, Bennett Alan and Bealer, Bonnie K. (2001). The World of Caffeine: The Science and Culture of the World's Most Popular Drug. Routledge. p. 228. ISBN 0-415-92722-6.
  60. ↑ Hicks, M. B.; Hsieh, Y-H. P. and Bell, L. N. (1996). "Tea preparation and its influence on methylxanthine concentration" (PDF). Food Research International 29 (3–4): 325–330. doi:10.1016/0963-9969(96)00038-5.
  61. ↑ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3459493/
  62. ↑ Graham, HN (1992). "Green tea composition, consumption, and polyphenol chemistry". Preventive medicine 21 (3): 334–50. doi:10.1016/0091-7435(92)90041-f. PMID 1614995.
  63. ↑ "Fluoride in Tea". I-sis.org.uk. Retrieved 24 January 2011.
  64. ↑ Fung, K. F.; Zhang, Z. Q.; Wong, J. W. C.; Wong, M. H. (1999). "Fluoride contents in tea and soil from tea plantations and the release of fluoride into tea liquor during infusion". Environmental Pollution 104 (2): 197. doi:10.1016/S0269-7491(98)00187-0.
  65. ↑ "Tea, brewed, prepared with tap water [black tea], one cup, USDA Nutrient Tables, SR-21". Conde Nast. 2014. Retrieved 25 October 2014.
  66. ↑ Ferruzzi, MG (2010). "The influence of beverage composition on delivery of phenolic compounds from coffee and tea". Physiol Behav 100 (1): 33–41. doi:10.1016/j.physbeh.2010.01.035. PMID 20138903.
  67. ↑ Williamson, G; Dionisi, F; Renouf, M (2011). "Flavanols from green tea and phenolic acids from coffee: critical quantitative evaluation of the pharmacokinetic data in humans after consumption of single doses of beverages". Mol Nutr Food Res 55 (6): 864–73. doi:10.1002/mnfr.201000631. PMID 21538847.
  68. ↑ Yang, CS; Chen, G; Wu, Q (2014). "Recent scientific studies of a traditional Chinese medicine, tea, on prevention of chronic diseases". J Tradit Complement Med 4 (1): 17–23. doi:10.4103/2225-4110.124326. PMID 24872929.
  69. ↑ Meydani, M; Hasan, ST (2010). "Dietary polyphenols and obesity". Nutrients 2 (7): 737–51. doi:10.3390/nu2070737.
  70. ↑ Darvesh, AS; et al. (2010). "Oxidative stress and Alzheimer's disease: dietary polyphenols as potential therapeutic agents". Expert Rev Neurother 10 (5): 729–45. doi:10.1586/ern.10.42.
  71. ↑ "Green Tea". National Center for Complementary and Integrative Health, US National Institutes of Health, Bethesda, MD. 2014. Retrieved 25 October 2014.
  72. ↑ "Summary of Qualified Health Claims Subject to Enforcement Discretion:Green Tea and Cancer". Food and Drug Administration, US Department of Health and Human Services. October 2014. Retrieved 25 October 2014.
  73. ↑ Troup R, Hayes JH, Raatz SK, Thyagarajan B, Khaliq W, Jacobs DR, Key NS, Morawski BM, Kaiser D, Bank AJ (2015). "Effects of black tea on blood cholesterol concentrations in individuals with mild hypercholeserolemia: A diet-controlled randomized trial". J Acad Nutr Diet 115 (2): 264–271. doi:10.1016/j.jand.2014.07.021. PMID 25266246.
  74. ↑ Liu Tong (2005). Chinese tea. Beijing: China Intercontinental Press. p. 137. ISBN 7-5085-0835-1.
  75. ↑ "Brief Guide to Tea". BriefGuides. 2006. Archived from the original on 22 August 2006. Retrieved 7 November 2006.
  76. ↑ "Some tea and wine may cause cancer – tannin, found in tea and red wine, linked to esophageal cancer", Nutrition Health Review, 22 September 1990.
  77. ↑ Tierra, Michael (1990). The Way of Herbs. Pocket Books. ISBN 0-671-72403-7.
  78. ↑ "How to make a perfect cuppa". BBC News. 25 June 2003. Retrieved 28 July 2006.
  79. ↑ Dubrin, Beverly (1 October 2010). Tea Culture: History, Traditions, Celebrations, Recipes & More. Charlesbridge Publishing. p. 24. ISBN 978-1-60734-363-9.
  80. ↑ Lorenz, M.; Jochmann, N.; Von Krosigk, A.; Martus, P.; Baumann, G.; Stangl, K.; Stangl, V. (2006). "Addition of milk prevents vascular protective effects of tea". European Heart Journal 28 (2): 219–223. doi:10.1093/eurheartj/ehl442. PMID 17213230.
  81. ↑ Gulati, Ashu; Sharma, Vaishali (November 2005). "Extractability of tea catechins as a function of manufacture procedure and temperature of infusion". Food Chemistry 93 (1): 141–148. doi:10.1016/j.foodchem.2004.10.016. Retrieved 7 December 2014.
  82. ↑ Snopes.com: "Steep risk." Retrieved 9 September 2015
  83. ↑ World tea production reaches new highs
  84. ↑ About Turkey:Geography, Economics, Politics, Religion and Culture, Rashid and Resit Ergener, Pilgrims' Process, 2002, 0-9710609-6-7, p.g. 41
  85. ↑ "Capacity Building Program on International Trade" (PDF) (Press release). Ministry of Agriculture. Retrieved 2013-01-26.
  86. ↑ Turkish Statistical Institute (11 August 2013). "En çok çay ve karpuz tüketiyoruz (in Turkish)/ We consume a lot of tea and watermelon". CNN Turk. Retrieved 24 August 2013.
  87. ↑ "tea"
  88. ↑ Burke, Andrew; Elliott, Mark; Mohammadi, Kamin and Yale, Pat (2004). Iran. Lonely Planet. pp. 75–76. ISBN 1-74059-425-8.
  89. ↑ "Tea will be declared a national drink, says Montek". The Hindu. 21 April 2012.
  90. ↑ "Tea to get hotter with national drink tag?". The Times Of India. 30 April 2012.
  91. ↑ "Tea will be declared national drink: Montek Singh Ahluwalia – India – IBNLive". Ibnlive.in.com. 21 April 2012. Retrieved 13 November 2012.
  92. ↑ "Tea". Modern Marvels television (program). The History Channel. Broadcast 15 October 2010.
  93. ↑ Sanyal, Amitava (13 April 2008). "How India came to be the largest tea drinking nation". Hindustan Times (New Delhi). p. 12.
  94. ↑ Euromonitor International (13 May 2013). "Turkey: Second biggest tea market in the world". Market Research World. Retrieved 25 November 2012.
  95. 1 2 3 Food and Agriculture Organization of the United Nations—Production FAOSTAT. Retrieved 30 April 2010.
  96. ↑ Agritrade Executive Brief on Tea, 2013 Retrieved 21 Feb 2014
  97. ↑ Blanchard, Ben (24 April 2012). "Greenpeace says finds tainted Lipton tea bags in China". Beijing: Reuters. Retrieved 26 March 2015.
  98. ↑ Griffith-Greene, Megar (8 March 2014). "Pesticide traces in some tea exceed allowable limits". CBC News. Retrieved 26 March 2015.
  99. ↑ Borreli, Lizette (22 August 2013). "Could Tea Be Bad For You? 5 Tea Ingredients That Are Harming Your Health". Medical Daily. IBT Media. Retrieved 25 March 2015.
  100. ↑ "Tea contains harmful pesticide residues: Study". Mumbai: The Times of India. 12 August 2014. Retrieved 26 March 2015.
  101. ↑ List of Goods Produced by Child Labor or Forced Labor
  102. ↑ "A Bitter Cup". War on Want. Retrieved 27 July 2010.
  103. ↑ Tocklai Tea Research Station Report
  104. ↑ United Nations. Economic and Social Commission for Asia and the Pacific (2002). Organic Agriculture and Rural Poverty Alleviation: Potential and Best Practices in Asia. United Nations Publications. pp. 62–63. ISBN 9211201381
  105. 1 2 Food and Agriculture Organization of the United Nations—Trade FAOSTAT
  106. 1 2 "IMPORTS: Commodities by country". Faostat.fao.org. Retrieved 24 January 2011.
  107. ↑ Thompkins, Gwen (16 September 2009). "In Kenya, Tea Auction Steeped In Tradition, Gentility: NPR". npr.org. Retrieved 18 September 2009.
  108. ↑ "Lipton Institute of Tea – Interview of Steve, Tea technology manager, Chapter: A Culture of Innovation". Lipton. 2008. Archived from the original on 2011-04-30. Retrieved 26 June 2008.
  109. ↑ "PG Tips – About Us". pgtips.co.uk. Archived from the original on 2007-01-20. Retrieved 17 February 2009.
  110. ↑ Smithers, Rebecca (2 July 2010). "Most UK teabags not fully biodegradeable, research reveals". The Guardian. Retrieved 4 May 2012.
  111. ↑ Mair & Hoh 2009, p. 50.
  112. ↑ Mair & Hoh 2009, p. 62.
  113. ↑ Mair & Hoh 2009, p. 48.
  114. ↑ Mair & Hoh 2009, p. 110.
  115. ↑ Mair & Hoh 2009, pp. 124–136.
  116. ↑ Blackburn, George (2012). The Guns of Normandy: A Soldier's Eye View, France 1944. Random House Digital, Inc. ISBN 1-55199-462-3
  117. ↑ "PT. Sinar Sosro". Retrieved 29 January 2016.
  118. ↑ "Bischofszell Food Ltd". Bina.ch. Retrieved 25 November 2012.
  119. ↑ "Green Tea Storage" (PDF). Retrieved 15 July 2009.
Sources

External links

This article is issued from Wikipedia - version of the Wednesday, May 04, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.