出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2015/08/10 20:08:53」(JST)
Oolong tea being infused in a gaiwan
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Type | Hot or cold beverage |
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Country of origin | China[1] |
Introduced | Approx. 10th century BC (earliest written records)[2] |
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] 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 China, possibly as a medicinal drink.[6] It came to the West via Portuguese priests and merchants, who introduced it during the 16th century.[7] Drinking tea became fashionable among Britons during the 17th century, 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.
The Chinese character for tea is 茶, originally written with an extra stroke as 荼 (pronounced tu, used as a word for a bitter herb), and acquired its current form during the Tang Dynasty as used in the eighth-century treatise on tea, The Classic of Tea.[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 tu (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 (dr- represents a single consonant for a retroflex d), which changed due to sound shift through the centuries.[14] Other ancient words for tea include jia (檟, defined as "bitter tu" during the Han Dynasty), she (蔎), ming (茗) and chuan (荈), with chuan the only other word still in use for tea.[14][15] Most, 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:[16]
The widespread form chai came from Persian چای chay. Both the châ and chây forms are found in Persian dictionaries.[17] They derive from Northern Chinese pronunciation of chá,[18] which passed overland to Central Asia and Persia, where it picked up the Persian grammatical suffix -yi before passing on to Russian, Arabic, Urdu, Turkish, etc.[19]
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.
Languages in more intense contact with Chinese, Sinospheric languages such as 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. Although normally pronounced as cha, Korean and Japanese also retain the early but now less common pronunciations of ta and da. Japanese has different pronunciations for the word tea depending on when the pronunciations were first borrowed into the language: Ta comes from the Tang Dynasty court at Chang'an--that is, from Middle Chinese; da, however, comes from the earlier Southern Dynasties court at Nanjing, a place where the consonant was still voiced, as it is today in neighbouring Shanghainese zo.[citation needed] Vietnamese and Zhuang have southern cha-type pronunciations.
Tea plants are native to East and South Asia, and probably originated around the meeting points of the lands of eastern India, north Burma and southwest China.[21] 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 Assam province of India, northern part of Burma, and Yunnan and Sichuan provinces of China.[21] Tea drinking likely began during the Shang Dynasty in China, when it was used for medicinal purposes.[6] It is believed that, soon after, "for the first time, 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.[20] A Chinese inventor was the first person to invent a tea shredder.[22] The first recorded drinking of tea is in China, with the earliest records of tea consumption dating to the 10th century BC.[2][23] Another 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." Another early reference to tea is found in a letter written by the Qin Dynasty general Liu Kun.[24] 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 Vietnam. In India, it has been drunk for medicinal purposes for a long but uncertain period, but apart from the Himalayan region seems not to have been used as a beverage until the British introduced Chinese tea there.
Tea was first introduced to Portuguese priests and merchants in China during the 16th century, at which time it was termed chá.[7] The first record in English is from Peter Mundy an East India Company agent writing to Macao requesting "the best sort of chaw" in 1615.[25] In 1750, tea experts travelled from China to the Azores, and planted tea, along with jasmine and mallow, to give it aroma and distinction. Both green and black tea continue to grow on the islands, which are the main suppliers to continental Portugal. Catherine of Braganza, wife of King Charles II of England, took the tea habit to Great Britain around 1660 when it was tasted by Samuel Pepys, but tea was not widely consumed in Britain until the 18th century, and remained expensive until the latter part of that period. Tea smuggling during the 18th century led to Britain’s masses being able to afford and consume tea, and its importance eventually influenced the Boston Tea Party. The British government eventually eradicated the tax on tea, thereby eliminating the smuggling trade by 1785.[26] In Britain and Ireland, tea had become an everyday beverage for all levels of society by the late 19th century, but at first it was consumed as a luxury item on special occasions, such as religious festivals, wakes, and domestic work gatherings such as quiltings.[27] The price in Europe fell steadily during the 19th century, especially after Indian tea began to arrive in large quantities.
The first European to successfully transplant tea to the Himalayas, Robert Fortune, was sent by the East India Company on a mission to China in 1848 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), at a time when westerners were not held in high regard.[28]
Tea was introduced into India by the British, in an attempt to break the Chinese monopoly on it.[29] The British brought Chinese seeds into Northeast India, but the plants failed; they later discovered that a different variety of tea was endemic to Assam and the northeast region of India and that it was used by a local tribe Siphung. 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.[29] Tea was originally consumed only by anglicized Indians; it became widely popular in India in the 1950s because of a successful advertising campaign by the India Tea Board.[29]
Camellia sinensis is an evergreen plant that grows mainly in tropical and subtropical climates.[30] Some varieties can also tolerate marine climates and are cultivated as far north as Cornwall in the United Kingdom,[31] Perthshire in Scotland,[32][33][34] Washington state in the United States,[35] Vancouver Island in Canada,[36] and experimentally in Pembrokeshire, Wales[37] in the Northern Hemisphere. In the Southern Hemisphere, tea is grown as far south as Hobart on the Australian island of Tasmania[38][39] and Waikato in New Zealand.[40]
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.[30] 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.[41] Many high-quality tea plants are cultivated at elevations of up to 1,500 m (4,900 ft) above sea level. While at these heights the plants grow more slowly, they acquire a better flavour.[42]
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,[43] 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,[30] 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.[44]
Only the top 1–2 in of the mature plant are picked. These buds and leaves are called 'flushes'.[45] 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.[30] 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.
Tea is generally divided into categories based on how it is processed.[46] 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.
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,[47] and brewing method.[48] 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.[49]
Tea also contains small amounts of theobromine and theophylline, which are stimulants and xanthines similar to caffeine.[50]
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.[51][52]
Nutritional value per 100 g (3.5 oz) | |
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Energy | 4.2 kJ (1.0 kcal) |
Carbohydrates
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0.3
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Fat
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0
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Protein
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0
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Trace minerals | |
Manganese |
(10%)
0.2 mg |
Other constituents | |
Water | 99.7 g |
Theobromine | 2 mg |
Caffeine | 20 mg |
Fluoride | 373 ug |
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Percentages are roughly approximated using US recommendations for adults. |
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.[53] Tea leaves contain diverse polyphenols, including flavonoids, epigallocatechin gallate (commonly noted as EGCG) and other catechins.[54][55]
It has been suggested that green and black tea may protect against cancer[56] or other diseases such as obesity[57] or Alzheimer's disease,[58] but the compounds found in green tea have not been conclusively demonstrated to have any effect on human diseases.[59][60] One human study demonstrated that regular consumption of black tea over four weeks had no beneficial effect in lowering blood cholesterol levels.[61]
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,[62] with 120,000 tons being consumed in Turkey, and the rest being exported.[63] In 2010 Turkey had the highest per capita consumption in the world at 2.7 kg.[64] As of 2013, the per-capita consumption of Turkish tea exceeds 10 cups per day and 13.8 kg per year.[65] Tea is grown mostly in Rize Province on the Black Sea coast.[66]
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 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, 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.[67]
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.[68][69] 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.[70]
In the United States, 80% of tea is consumed as iced tea.[71] Sweet tea is native to the southeastern US, and is iconic in its cuisine.
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 are also added to the concoction. Apart from classic flavours like lemon and peach, exotic flavours like jasmine and lemongrass are also very popular.
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 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 the UK, '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.
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The traditional method of preparing tea is to place loose tea leaves directly (or in a tea infuser) into a tea pot or teacup, pour freshly boiled water over the leaves, and allow the infused liquid to steep (or "brew"). After a few minutes, the infuser is removed, or the tea is poured through a strainer while serving. Strength should be varied by the amount of tea leaves used, not changing the steeping time.
Most green teas should be allowed two or three minutes, although other types may vary between thirty seconds and ten minutes.
Quantity also varies by tea type, with a basic recipe calling for one slightly heaped teaspoon (about 5 ml) for each teacup of water (200–240 ml) (7–8 oz). Stronger teas to be drunk with milk (such as Assam) are often prepared more heavily, while more delicate high-grown varieties (such as a Darjeeling) more lightly.
Optimum brewing temperature depends on tea type. Camellia sinensis naturally contains tannins having bitter properties accentuated by both temperature and steeping time. These tannins are enhanced by oxidation during processing. Teas with little or no oxidation, such as a green or white, are best at lower temperatures between 65 and 85 °C (149 and 185 °F), while more oxidized teas require 100 °C (212 °F) to extract their large, complex, flavourful phenolic molecules.
In addition, boiling reduces the dissolved oxygen content of water, which would otherwise react with phenolic molecules to degrade them.
Type | Water temp. | Steep time | Infusions |
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White tea | 65 to 70 °C (149 to 158 °F) | 1–2 minutes | 3 |
Yellow tea | 70 to 75 °C (158 to 167 °F) | 1–2 minutes | 3 |
Green tea | 75 to 80 °C (167 to 176 °F) | 1–2 minutes | 4–6 |
Oolong tea | 80 to 85 °C (176 to 185 °F) | 2–3 minutes | 4–6 |
Black tea | 99 °C (210 °F) | 2–3 minutes | 2–3 |
Flowering tea | 100 °C (212 °F) | 2–3 minutes | 4–5 |
Pu'er tea | 95 to 100 °C (203 to 212 °F) | Limitless | Several |
Tisanes | 99 °C (210 °F) | 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 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, although different teas open up differently and may require more infusions to produce the best flavour.[72]
One way to taste a tea throughout its entire process is to add hot water to a cup containing the leaves and sample it every 30 seconds. As the tea leaves unfold (known as "The Agony of the Leaves") the taste evolves.[73]
A tea cosy or a teapot warmer are often used to keep the temperature of the tea in a teapot constant over periods of 20–60 minutes.
Popular varieties of black tea include Assam, Iran,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).[74] 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.
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 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 should be brewed around 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.
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 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.
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.
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.[citation needed] 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]
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.
Alcohol, such as whisky or brandy, may also be added to tea.
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.
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,[81] 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.[82]
In 2003, world tea production was 3.21 million tonnes annually.[83] In 2010, world tea production reached over 4.52 million tonnes after having increased by 5.7% between 2009 and 2010.[84] Production rose by 3.1% between 2010 and 2011. The largest producers of tea are the People's Republic of China, India, Kenya, Sri Lanka, and Turkey.
The following table shows the amount of tea production (in tonnes) by leading countries in recent years. Data are generated by the Food and Agriculture Organization of the United Nations as of February 2012.[83]
Rank | Country[83] | 2008 | 2009 | 2010 | 2011 |
---|---|---|---|---|---|
1 | China | 1,257,600 | 1,359,000 | 1,450,000 | 1,623,000 |
2 | India | 987,000 | 972,700 | 991,180 | 1,063,500 |
3 | Kenya | 345,800 | 314,100 | 399,000 | 377,912 |
4 | Sri Lanka | 318,700 | 290,000 | 282,300 | 327,500 |
5 | Turkey | 198,046 | 198,601 | 235,000 | 221,600 |
6 | Vietnam | 173,500 | 185,700 | 198,466 | 206,600 |
7 | Iran | 165,717 | 165,717 | 165,717 | 162,517 |
8 | Indonesia | 150,851 | 146,440 | 150,000 | 142,400 |
9 | Argentina | 80,142 | 71,715 | 88,574 | 96,572 |
10 | Japan | 96,500 | 86,000 | 85,000 | 82,100 |
Total | World | 4,211,397 | 4,242,280 | 4,518,060 | 4,321,011 |
Multiple recent reports have found that most Chinese and Indian teas contain residues of banned toxic pesticides.[85][86][87][88]
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[89] (a report on the worst forms of child labor).
Workers who pick and pack tea on plantations in developing countries can face harsh working conditions and may earn below the living wage.[90]
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,[citation needed] 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.[91] 6,000 tons of organic tea were sold in 1999.[92] About 75% of organic tea production is sold in France, Germany, Japan, the United Kingdom, and the United States.[citation needed]
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.[93] Kenya, China, India and Sri Lanka were the largest exporters of tea in 2007 (with exports of: 374229, 292199, 193459 and 190203 tonnes respectively).[93][94] The largest exporter of black tea is Kenya, largest producer (and consumer) India.[94][95]
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[96] and PG Tips/Scottish Blend in 1996,[97] 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.[citation needed] 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.[98]
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 (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.[99] 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.[100]
Compressed tea was the most popular form of tea in China during the Tang dynasty.[101] By the beginning of the Ming dynasty, it had been displaced by loose leaf tea.[102] 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.[103]
"Instant tea", both hot and cold, is an alternative to the brewed products. Similar to freeze-dried instant coffee, but not requiring boiling water, instant tea was developed in the 1930s. Nestlé introduced 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...[104]
Canned tea is sold prepared and ready to drink. It was introduced in 1981 in Japan.
In 1983, Swiss-based Bischofszell Food Ltd., was the first company to bottle ice tea on an industrial scale.[105]
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).[106]
Da Hong Pao tea, an oolong tea
Fuding Bai Hao Yinzhen tea, a white tea
Green pu-erh tuo cha, a type of compressed raw pu-erh
Huoshan Huangya tea, a yellow tea
Loose dried tea leaves
Taiwanese High Mountain oolong
A spicy Thai salad made with young, fresh tea leaves
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By the time of the Shang dynasty (1766–1050 BC), tea was being consumed in Yunnan Province for its medicinal properties
The Portuguese traders and the Portuguese Jesuit priests, who like Jesuits of every nation busied themselves with the affairs of caffeine, wrote frequently and favorably to compatriots in Europe about tea.
Chai: A beverage made from spiced black tea, honey, and milk. ETYMOLOGY: Ultimately from Chinese (Mandarin) chá.
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.
year 1996–2012
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.
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.
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リンク元 | 「茶」「Camellia sinensis」 |
拡張検索 | 「tear gas」 |
関連記事 | 「TEA」 |
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