Friday, July 10, 2009

Tea


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For other uses, see Tea (disambiguation).
Green Tea leaves in a Chinese gaiwan.
A tea bush.
Plantation workers picking tea in Tanzania.
Tea plant (Camellia sinensis) from Köhler's Medicinal Plants.
Loose dried tea leaves

Tea refers to the agricultural products of the leaves, leaf buds, and internodes of the Camellia sinensis plant, prepared and cured by various methods. "Tea" also refers to the aromatic beverage prepared from the cured leaves by combination with hot or boiling water[1], and is the colloquial name for the Camellia sinensis plant itself.

After water, tea is the most widely-consumed beverage in the world.[2] It has a cooling, slightly bitter, astringent flavour.[3]

The four types of tea most commonly found on the market are black tea, oolong tea, green tea and white tea,[4] all of which can be made from the same bushes, processed differently, and in the case of fine white tea grown differently. Pu-erh tea, a double-fermented black tea, is also often classified as amongst the most popular types of tea.[5]

The term "herbal tea" usually refers to an infusion or tisane of leaves, flowers, fruit, herbs or other plant material that contains no Camellia sinensis.[6] The term "red tea" either refers to an infusion made from the South African rooibos plant, also containing no Camellia sinensis, or, in Chinese, Korean, Japanese and other East Asian languages, refers to black tea.

Contents

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[edit] Cultivation

Camellia sinensis is an evergreen plant that grows mainly in tropical and sub-tropical climates. Nevertheless, some varieties can also tolerate marine climates and are cultivated as far north as Cornwall on the UK mainland[7] and Seattle in the United States.

In addition to a zone 8 climate or warmer, tea plants require at least 50 inches of rainfall a year and prefer acidic soils.[8] Many high-quality tea plants are cultivated at elevations of up to 1500 meters (5,000 ft): at these heights, the plants grow more slowly and acquire a better flavour.[9]

Only the top 1-2 inches of the mature plant are picked. These buds and leaves are called flushes.[10] A plant will grow a new flush every seven to ten days during the growing season.

A tea plant will grow into a tree if left undisturbed, but cultivated plants are pruned to waist height for ease of plucking.[11]

Two principal varieties are used: the small-leaved China plant (C. sinensis sinensis), used for most Chinese, Formosan and Japanese teas, for thousands of years , (but not Pu-erh); and the large-leaved Assam plant (C. sinensis assamica), likely to have been started to be cultivated since the 18th Century , used in most Indian and other teas (but not Darjeeling). Within these botanical varieties, especially the small-leaved China plant, there are many traditional strains and modern Indian clonal varieties. Leaf size is the chief criterion for the classification of tea plants:[12] tea is classified into (1) Assam type, characterized by the largest leaves, possibly because of the Indian clonal varieties with the China plant ; (2) China type, characterized by the smallest leaves; and (3) Cambod, characterized by leaves of intermediate size.[12]

[edit] Processing and classification

Main article: Tea processing

A tea's type is determined by the processing which it undergoes. The traditional Chinese tea processing methodical technology and records says :Leaves of Camellia sinensis soon begin to wilt and oxidize if not dried quickly after picking. The leaves turn progressively darker as their chlorophyll breaks down and tannins are released. This process, enzymatic oxidation, is called fermentation in the tea industry, although it is not a true fermentation: it is not caused by micro-organisms, and is not an anaerobic process. The next step in processing is to stop the oxidation process at a predetermined stage by heating, which deactivates the enzymes responsible. With black tea this is done simultaneously with drying.

Without careful moisture and temperature control during manufacture and packaging, the tea will grow fungi. The fungus causes real fermentation that will contaminate the tea with toxic and sometimes carcinogenic substances, as well as off-flavors, rendering the tea unfit for consumption.

Tea leaf processing methods (Simplified)

Tea is traditionally classified based on the techniques with which it is produced and processed.[13]

[edit] Blending and additives

Tea weighing station north of Batumi, Russian Empire before 1915
Main article: Tea blending and additives

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

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

[edit] Content

Tea contains catechins, a type of antioxidant. In a fresh tea leaf, catechins can compose up to 30% of the dry weight. Catechins are highest in concentration in white and green teas, while black tea has substantially fewer due to its oxidative preparation[14][15]. Research by the U.S. Department of Agriculture has suggested that levels of antioxidants in green and black tea do not differ greatly, with green tea having an Oxygen Radical Absorbance Capacity (ORAC) of 1253 and black tea an ORAC of 1128 (measured in μmolTE/100g).[16] Tea also contains theanine and the stimulant caffeine at about 3% of its dry weight, translating to between 30 mg and 90 mg per 8 oz (250 ml) cup depending on type, brand[17] and brewing method.[18] Tea also contains small amounts of theobromine and theophylline,[19] as well as fluoride, with certain types of brick tea made from old leaves and stems having the highest levels.[20]

Dry tea has more caffeine by weight than coffee; nevertheless, more dried coffee is used than dry tea in preparing the beverage,[21] which mean that a cup of brewed tea contains significantly less caffeine than a cup of coffee of the same size.

Tea has no carbohydrates, fat, or protein.

[edit] Origin and history

According to Mondal (2007, p. 519): "Camellia sinensis originated in southeast Asia, specifically around the intersection of latitude 29°N and longitude 98°E, the point of confluence of the lands of northeast India, north Burma, southwest China and Tibet. The plant was introduced to more than 52 countries, from this ‘centre of origin’." But, in the tea natural history, Camellia sinensis sinensis originated in south/southeast China, specifically between 23th-30th parallel north/latitude 23'N-30'N and 100th-121th meridian east/longitude 100'E-121'E, the regions of lands of east China, southeast China, south China and a few regions of the states of TibetChina and YunnanChina in the southwest China .

Based on morphological differences between the Assamese and Chinese varieties, botanists have long asserted a dual botanical origin for tea; however, statistical cluster analysis, the same chromosome number (2n=30), easy hybridization, and various types of intermediate hybrids and spontaneous polyploids all appear to demonstrate a single place of origin for Camellia sinensis — the area including the northern part of Burma, and Yunnan and Sichuan provinces of China.[22] With the hybridizing techniques used, trying to achieve the same hours of labour for bigger harvests of tea, since the 19th Century, the Camellia sinensis assamica hybrids plants, with the 18th Century initial thousands of stolen Chinese tea plants, in the southeast Asia regions may have been the products of the 19th Century and 20th Century clonal/hybridizing experiments .

Yunnan Province has also been identified as "the birthplace of tea...the first area where humans figured out that eating tea leaves or brewing a cup could be pleasant".[23] Fengqing County in the Lincang City Prefecture of Yunnan Province is said to be home to the world's oldest cultivated tea tree, some 3,200 years old.[24]

[edit] Origin myths

In one popular Chinese legend, Shennong, the legendary Emperor of China and inventor of agriculture and Chinese medicine was drinking a bowl of boiling water some time around 2737 BC when a few leaves were blown from a nearby tree into his water, changing the color. The emperor took a sip of the brew and was pleasantly surprised by its flavor and restorative properties. A variant of the legend tells that the emperor tested the medical properties of various herbs on himself, some of them poisonous, and found tea to work as an antidote.[25] Shennong is also mentioned in Lu Yu's famous early work on the subject, Cha Jing.[26] A similar Chinese legend goes that the god of agriculture would chew the leaves, stems, and roots of various plants to discover medicinal herbs. If he consumed a poisonous plant, he would chew tea leaves to counteract the poison.[27]

A rather gruesome legend dates back to the Tang Dynasty. In the legend, Bodhidharma, the founder of Chan Buddhism, accidentally fell asleep after meditating in front of a wall for nine years. He woke up in such disgust at his weakness that he cut off his own eyelids. They fell to the ground and took root, growing into tea bushes.[28] Sometimes, another version of the story is told with Gautama Buddha in place of Bodhidharma[29].

Whether or not these legends have any basis in fact, tea has played a significant role in Asian culture for centuries as a staple beverage, a curative, and a status symbol. It is not surprising, therefore, that theories of its origin are often religious or royal in nature.

A Ming Dynasty painting by artist Wen Zhengming illustrating scholars greeting in a tea ceremony
Lu Yu's statue in Xi'an
Illustration of the legend of monkeys harvesting tea.

[edit] China

Main article: History of tea in China

The Chinese have consumed tea for thousands of years. People of the Han Dynasty used tea as medicine (though the first use of tea as a stimulant is unknown). China is considered to have the earliest records of tea consumption[30][31], with records dating back to the 10th century BC.[30]

Laozi (ca. 600-517 BC), the classical Chinese philosopher, described tea as "the froth of the liquid jade" and named it an indispensable ingredient to the elixir of life. Legend has it that master Lao was saddened by society's moral decay and, sensing that the end of the dynasty was near, he journeyed westward to the unsettled territories, never to be seen again. While passing along the nation's border, he encountered and was offered tea by a customs inspector named Yin Hsi. Yin Hsi encouraged him to compile his teachings into a single book so that future generations might benefit from his wisdom. This then became known as the Dao De Jing, a collection of Laozi's sayings. To honor Yin's generosity and its effect on the book's creation, a national custom of offering tea to guests began in China.[citation needed]

In 59 BC, Wang Bao wrote the first known book with instructions on buying and preparing tea, establishing that, at this time, tea was not only a medicine but an important part of diet.[citation needed]

In 220 , famed physician and surgeon Hua Tuo wrote Shin Lun, in which he describes tea's ability to improve mental functions: "to drink k'u t'u [bitter tea] constantly makes one think better..."[citation needed]

During the Sui Dynasty (589-618 AD) tea was introduced to Japan by Buddhist monks.[citation needed]

The Tang Dynasty writer Lu Yu's (simplified Chinese: 陆羽; traditional Chinese: 陸羽; pinyin: lùyǔ) Cha Jing (The Classic of Tea) （simplified Chinese: 茶经; traditional Chinese: 茶經; pinyin: chá jīng) is an early work on the subject. (See also Tea Classics) According to Cha Jing tea drinking was widespread. The book describes how tea plants were grown, the leaves processed, and tea prepared as a beverage. It also describes how tea was evaluated. The book also discusses where the best tea leaves were produced. Teas produced in this period were mainly tea bricks which were often used as currency, especially further from the center of the empire where coins lost their value.

During the Song Dynasty (960-1279), production and preparation of all tea changed. The tea of Song included many loose-leaf styles (to preserve the delicate character favored by court society), but a new powdered form of tea emerged. Steaming tea leaves was the primary process used for centuries in the preparation of tea. After the transition from compressed tea to the powdered form, the production of tea for trade and distribution changed once again. The Chinese learned to process tea in a different way in the mid-13th century. Tea leaves were roasted and then crumbled rather than steamed. This is the origin of today's loose teas and the practice of brewed tea.

Tea production in China, historically, was a laborious process, conducted in distant and often poorly accessible regions. This led to the rise of many apocryphal stories and legends surrounding the harvesting process. For example, one story that has been told for many years is that of a village where monkeys pick tea. According to this legend, the villagers stand below the monkeys and taunt them. The monkeys, in turn, become angry, and grab handfuls of tea leaves and throw them at the villagers.[32] There are products sold today that claim to be harvested in this manner, but no reliable commentators have observed this firsthand, and most doubt that it happened at all.[33] For many hundreds of years the commercially-used tea tree has been, in shape, more of a bush than a tree.[34] "Monkey picked tea" is more likely a name of certain varieties than a description of how it was obtained.[35]

In 1391, the Ming court issued a decree that only loose tea would be accepted as a "tribute." As a result, loose tea production increased and processing techniques advanced. Soon, most tea was distributed in full-leaf, loose form and steeped in earthenware vessels.

[edit] Japan

Ancient Tea Urns used by merchants to store tea.
Japanese tea ceremony
Main article: History of tea in Japan

Tea use spread to Japan about the sixth century.[36] Tea became a drink of the religious classes in Japan when Japanese priests and envoys, sent to China to learn about its culture, brought tea to Japan. Ancient recordings indicate the first batch of tea seeds were brought by a priest named Saichō (最澄?, 767-822) in 805 and then by another named Kūkai (空海?, 774-835) in 806. It became a drink of the royal classes when Emperor Saga (嵯峨天皇?), the Japanese emperor, encouraged the growth of tea plants. Seeds were imported from China, and cultivation in Japan began.

In 1191, the famous Zen priest Eisai (栄西?, 1141-1215) brought back tea seeds to Kyoto. Some of the tea seeds were given to the priest Myoe Shonin, and became the basis for Uji tea. The oldest tea specialty book in Japan, Kissa Yōjōki (喫茶養生記?, How to Stay Healthy by Drinking Tea), was written by Eisai. The two-volume book was written in 1211 after his second and last visit to China. The first sentence states, “Tea is the ultimate mental and medical remedy and has the ability to make one’s life more full and complete." Eisai was also instrumental in introducing tea consumption to the warrior class, which rose to political prominence after the Heian Period.

Green tea became a staple among cultured people in Japan—a brew for the gentry and the Buddhist priesthood alike. Production grew and tea became increasingly accessible, though still a privilege enjoyed mostly by the upper classes. The tea ceremony of Japan was introduced from China in the 15th century by Buddhists as a semi-religious social custom. The modern tea ceremony developed over several centuries by Zen Buddhist monks under the original guidance of the monk Sen no Rikyū (千 利休?, 1522-1591). In fact, both the beverage and the ceremony surrounding it played a prominent role in feudal diplomacy.

In 1738, Soen Nagatani developed Japanese sencha (煎茶?), literally roasted tea, which is an unfermented form of green tea. It is the most popular form of tea in Japan today. In 1835, Kahei Yamamoto developed gyokuro (玉露?), literally jewel dew, by shading tea trees during the weeks leading up to harvesting. At the end of the Meiji period (1868-1912), machine manufacturing of green tea was introduced and began replacing handmade tea.

[edit] Vietnam

Vietnamese green teas have been largely unknown outside of mainland Asia until the present day. Recent free-enterprise initiatives are introducing these green teas to outside countries through new export activities.

Types:

  • Lotus tea is a specialty product of the Vietnamese tea industry. Generally, high-quality green tea leaves are placed within lotus flowers for a day to acquire the scent, then are removed and packaged. A higher grade of lotus tea is made with lotus petals mixed in with high quality green tea leaves. Green tea style of Vietnam is to roll the leaves gently into crescents, and minimal handling. Vietnamese green teas are typically very potent. They are best brewed for most tastes for under 2 minutes using water temperature of 160°F. Beyond this time the tea will acquire a bitter taste that is nevertheless fancied by many tea lovers, as it reflects the potency of the tea leaves. Some fanciers will brew 3-4 times from one set of leaves, preferring the narrower flavor range of the later brewings.
  • Jasmine tea is produced in two grades similar to lotus tea. Lotus tea is considered a specialty and is reserved for events or special meals. Jasmine tea is popular as a "chaser" for Vietnamese iced coffee, and is poured into the glass after the coffee is consumed, allowed to chill, and then enjoyed as a follow-up to the iced coffee in coffee shop cafes, particularly in the night life of major cities, where coffee shops are a popular social rendezvous on hot evenings.
  • Artichoke Tea

Vietnamese teas are produced in many areas that have been known for tea-house "retreats". For example some are, located amidst immense tea forests of the Lamdong highlands, where there is a community of ancient Ruong houses built at the end of the 18th century.

[edit] Korea

See also: Korean tea ceremony and Korean tea
Darye, Korean tea ceremony

The first historical record documenting the offering of tea to an ancestral god describes a rite in the year 661 in which a tea offering was made to the spirit of King Suro, the founder of the Geumgwan Gaya Kingdom (42-562). Records from the Goryeo Dynasty (918-1392) show that tea offerings were made in Buddhist temples to the spirits of revered monks.

During the Joseon Dynasty (1392-1910), the royal Yi family and the aristocracy used tea for simple rites. The "Day Tea Rite" was a common daytime ceremony, whereas the "Special Tea Rite" was reserved for specific occasions. Toward the end of the Joseon Dynasty, commoners joined the trend and used tea for ancestral rites, following the Chinese example based on Zhu Xi's text formalities of Family.

Stoneware was common, ceramic more frequent, mostly made in provincial kilns, with porcelain rare, imperial porcelain with dragons the rarest. The earliest kinds of tea used in tea ceremonies were heavily pressed cakes of black tea, the equivalent of aged pu-erh tea still popular in China. However, importation of tea plants by Buddhist monks brought a more delicate series of teas into Korea, and the tea ceremony. Green tea, "chaksol" or "chugno," is most often served. However other teas such as "Byeoksoryung" Chunhachoon, Woojeon, Jakseol, Jookro, Okcheon, as well as native chrysanthemum tea, persimmon leaf tea, or mugwort tea may be served at different times of the year.

[edit] Taiwan

Taiwan is famous for the making of Oolong tea and green tea, as well as many western-styled teas. Bubble Tea or "Zhen Zhu Nai Cha" is black tea mixed with sweetened condensed milk and tapioca. Since the island was known to Westerners for many centuries as Formosa — short for the Portuguese Ilha Formosa, or "beautiful island" — tea grown in Taiwan is often identified by that name.

Middle Eastern tea

[edit] Tea spreads to the world

A conical urn-shaped silver-plated samovar used for boiling water for tea in Russia and some Middle eastern countries

The earliest record of tea in a more occidental writing is said to be found in the statement of an Arabian traveler, that after the year 879 the main sources of revenue in Canton were the duties on salt and tea. Marco Polo records the deposition of a Chinese minister of finance in 1285 for his arbitrary augmentation of the tea taxes. The travelers Giovanni Batista Ramusio (1559), L. Almeida (1576), Maffei (1588), and Teixeira (1610) also mentioned tea. In 1557, Portugal established a trading port in Macau and word of the Chinese drink "chá" spread quickly, but there is no mention of them bringing any samples home. In the early 17th century, a ship of the Dutch East India Company brought the first green tea leaves to Amsterdam from China. Tea was known in France by 1636. It enjoyed a brief period of popularity in Paris around 1648. The history of tea in Russia can also be traced back to the seventeenth century. Tea was first offered by China as a gift to Czar Michael I in 1618. The Russian ambassador tried the drink; he did not care for it and rejected the offer, delaying tea's Russian introduction by fifty years. In 1689, tea was regularly imported from China to Russia via a caravan of hundreds of camels traveling the year-long journey, making it a precious commodity at the time. Tea was appearing in German apothecaries by 1657 but never gained much esteem except in coastal areas such as Ostfriesland.[37] Tea first appeared publicly in England during the 1650s, where it was introduced through coffee houses. From there it was introduced to British colonies in America and elsewhere.

[edit] United Kingdom

Tea plantation in the Cameron Highlands, Malaysia.

The importing of tea into Britain began in the 1660s with the marriage of King Charles II with the Portuguese princess Catherine of Braganza where she brought to the court the habit of drinking tea.[38] On 25 September of the same year Samuel Pepys recorded in his diary: "I did send for a cup of tee (a China drink) of which I never had drank before".[39] It is probable that early imports came via Amsterdam or through sailors on eastern boats.[38]

Regular trade began in Guangzhou (Canton).[38] Trade was controlled by two monopolies: the Chinese Hongs (trading companies) and the British East India Company.[38] The Hongs acquired tea from 'the tea men' who had an elaborate supply chain into the mountains and provinces where the tea was grown.[38]

The East India Company brought back many products, of which tea was just one, but it was to prove one of the most successful.[38] It was initially promoted as a medicinal beverage or tonic.[38] By the end of the seventeenth century tea was taken as a drink, albeit mainly by the aristocracy.[38] In 1690 nobody would have predicted that by 1750 tea would be the national drink.[38] The origin of large trade in tea was the need for a return cargo from the East Indies. Merchantmen ships delivered fabrics manufactured in Britain to India and China but would return empty or partially full. To solve this problem the East India Company began a vigorous public relations campaign to popularise tea among the common people in Britain and develop it as a viable return cargo.

The escalation of tea importation and sales over the period 1690 to 1750 is mirrored closely by the increase in importation and sales of cane sugar: the British were not drinking just tea but sweet tea.[38] Thus, two of Britain's trading triangles were to meet within the cup: the sugar sourced from Britain's trading triangle encompassing Britain, Africa and the West Indies and the tea from the triangle encompassing Britain, India and China.[38]

So by 1830's, The East India Company and their accomplices, with the greed of the then Indians, shipped tens of thousands of illegally dug-up whole Chinese Tea Plants and Chinese Tea Plant cuttings to the now east India, Meghalaya, Assam, and later to the Manipur, Mizoram, Sri Lanka and small parts of the west Burma regions .

Britain had to pay China for its tea, but China had little need of British goods, so much of it was paid for with silver bullion. Although the then China did not need the silver, China Government eventually accepted the silver as the payments for the first few Good Chinese Tea Shipments . A few years on, the greedy Indian influenced the then East India Company, Britain to pay gold and silver for their addiction of the Indian opium, and forced the Chinese Tea Growers to accept the illegal Indian opium for the exchange of shipments of the Good Chinese Tea . Critics of tea at this time would point to the damage caused to Britain's wealth by this loss of bullion.[38] As an alternative, Britain began producing opium in India and forced China to trade tea for opium as part of several treaties after the Opium wars. Tea became an important lubricant of Britain's global trade, contributing to Britain's global dominance by the end of the eighteenth century. To this day tea is seen as a symbol of 'Britishness', but also, to some, as a symbol of British Colonialism.[38] The London 2012 section of the paralympic handover in Beijing included tea as part of the routine[clarification needed], such is the strong connection made between Britain and tea. Tea is widely drunk throughout the nation.

[edit] United States of America

While coffee is by far more popular, hot brewed black tea is enjoyed both with meals and as a refreshment by much of the population. Similarly, iced tea is consumed throughout. In the Southern states sweet tea, sweetened with large amounts of sugar or an artificial sweetener and chilled, is the fashion. Outside the South, sweet tea is sometimes found, but primarily because of cultural migration and commercialization.[citation needed]

The American specialty tea market has quadrupled in the years from 1993-2008, now being worth $6.8 billion a year.[40] Similar to the trend of better coffee and better wines, this tremendous increase was partly due to consumers who choose to trade up. Specialty tea houses and retailers also started to pop up during this period.[41]

The Boston Tea Party was an act of protest by the American colonists against the British Government in which they destroyed many crates of tea belonging to the British East India Company on ships in Boston Harbor. The incident, which took place on Thursday, December 16, 1773, has been seen as helping to spark the American Revolution.[citation needed]

Tea Garden in Assam, India

[edit] India

See also: Assam tea, Darjeeling tea, Masala chai, and Nilgiri tea

Tea had been known for millennia in India as a medicinal plant, but was not drunk for pleasure until the British began to establish plantations in the 19th century. The Chinese variety is used for Darjeeling tea, and the Assamese variety, native to the Indian state of Assam, everywhere else. The British introduced tea-growing into India in 1836 and into Ceylon (Sri Lanka) in 1867. At first they used seeds from China, but later seeds from the Assam plant were used."[42] Only black tea was produced until recent decades.

India was the top producer of tea for nearly a century, but was displaced by China as the top tea producer in the 21st century.[43] Indian tea companies have acquired a number of iconic foreign tea enterprises including British brands Tetley and Typhoo.[43] The per capita consumption of tea in India remains a modest 750 grams per person every year due to the large population base.[43] A lot of huge companies have emerged including 'Golden Tips Tea Co', and many other major brands that specialise and emphasize on Darjeeling tea and tourism in Darjeeling, one of the prime beautiful locations famous for tea.

[edit] Sri Lanka/Ceylon

Tea Garden in Sri Lanka
Main article: Tea production in Sri Lanka

Sri Lanka is renowned for its high quality tea and as the fourth biggest tea producing country globally, after China, India and Kenya (See the chart below) and has a production share of 9% in the international sphere, and one of the world's leading exporters with a share of around 19% of the global demand. The total extent of land under tea cultivation has been assessed at approximately 187,309 hectares.

The plantations started by the British were initially taken over by the government in the 1960s, but have been privatized and are now run by 'plantation companies' which own a few 'estates' or tea plantations each.

Ceylon tea is divided into 3 groups as Upcountry, Mid country and Low country tea based on the geography of the land on which it is grown. [44]

[edit] Africa and South America

Africa and South America have seen greatly increased tea production in recent decades, the great majority for export to Europe and North America respectively, produced on large estates, often owned by tea companies from the export markets. Almost all production is of basic mass-market teas, processed by the Crush, Tear, Curl method. Kenya is now the fourth largest global producer (figures below), after China and India, and is now the largest exporter of tea to the United Kingdom. There is also a great consumption of tea in Chile[citation needed]. In South Africa, the non-Camellia sinensis beverage rooibos is popular. In South America, yerba mate, a tisane, is popular.

[edit] Tea and health

Main article: Tea and health

The health benefits of tea is a controversial topic with many proponents and detractors. An article from the Nutrition (1999, pp. 946–949) journal as related on PubMed states:

The possible beneficial effects of tea consumption in the prevention of cancer and cardiovascular diseases have been demonstrated in animal models and suggested by studies in vitro. Similar beneficial effects, however, have not been convincingly demonstrated in humans: beneficial effects have been demonstrated in some studies but not in others. If such beneficial effects do exist in humans, they are likely to be mild, depending on many other lifestyle-related factors, and could be masked by confounding factors in certain populations. Another concern is that the amounts of tea consumed by humans are lower than the doses required for demonstrating the disease-prevention effects in animal models. Caution should be applied, however, in the use of high concentrations of tea for disease prevention. Ingestion of large amounts of tea may cause nutritional and other problems because of the caffeine content and the strong binding activities of tea polyphenols, although there are no solid data on the harmful effects of tea consumption. More research is needed to elucidate the biologic activities of green and black tea and to determine the optimal amount of tea consumption for possible health-beneficial effects.

In abstract, the health benefits of tea have been shown in animal studies, but at doses much higher than regularly consumed by humans, at which dosage levels may prove to be harmful to health.

Several of the potential health benefits proposed for tea are outlined in this excerpt from Mondal (2007, pp. 519–520) as following:

Tea leaves contain more than 700 chemicals, among which the compounds closely related to human health are flavanoides, amino acids, vitamins (C, E and K), caffeine and polysaccharides. Moreover, tea drinking has recently proven to be associated with cell-mediated immune function of the human body. Tea plays an important role in improving beneficial intestinal microflora, as well as providing immunity against intestinal disorders and in protecting cell membranes from oxidative damage. Tea also prevents dental caries due to the presence of fluorine. The role of tea is well established in normalizing blood pressure, lipid depressing activity, prevention of coronary heart diseases and diabetes by reducing the blood-glucose activity. Tea also possesses germicidal and germistatic activities against various gram-positive and gram negative human pathogenic bacteria. Both green and black tea infusions contain a number of antioxidants, mainly catechins that have anti-carcinogenic, anti-mutagenic and anti-tumoric properties.

In a large study of over 11,000 men and women completed in 1993 and published in the 1999 Journal of Epidemiology and Community Health (1999, pp. 481-487), there was actually shown an increase in the risk of coronary disease with the regular consumption of tea.

[edit] Etymology and cognates in other languages

The Chinese character for tea is 茶, but it is pronounced differently in the various Chinese dialects. Two pronunciations have made their way into other languages around the world[45]. One is tê, which comes from the Amoy Min Nan dialect, spoken around the port of Xiamen (Amoy). This pronunciation is believed to come from the old words for tea 梌 (tú) or 荼 (tú). The other is chá, used by the Cantonese dialect spoken around the ports of Guangzhou (Canton), Hong Kong, Macau, and in overseas Chinese communities, as well as in the Mandarin dialect of northern China. This term was used in ancient times to describe the first flush harvest of tea. Yet another different pronunciation is zu, used in the Wu dialect spoken around Shanghai. The words for tea in Korea and Japan are 차 and 茶 (ちゃ), respectively. Both are transliterated as cha. (In Japanese, it is sometimes 御茶 (おちゃ) or ocha, which is more polite.)

[edit] The derivatives from tê

Language Name Language Name Language Name Language Name Language Name
Afrikaans tee Armenian, Catalan te Czech té or thé (1) Danish te Dutch thee
English tea Esperanto teo Estonian tee Faroese te Finnish tee
French thé West Frisian tee Galician té German Tee Hebrew תה, te
Hungarian tea Icelandic te Indonesian teh Irish tae Italian tè or thè
Javanese tèh Korean 茶,다 da [ta](2) scientific Latin thea Latvian tēja Leonese té
Limburgish tiè Low Saxon Tee [tʰɛˑɪ] or Tei [tʰaˑɪ] Malay teh Norwegian te Occitan tè
Sesotho tea,chá Scots Gaelic tì, teatha Singhalese thé Spanish té Scots tea [tiː] ~ [teː]
Sundanese entèh Swedish te Tamil தேநீர் thenīr (nīr = water) "theyilai" means "tea leaf" (ilai=leaf) Telugu తేనీళ్ళు tēnīru Welsh te
  • Note: (1) té or thé, but this term is considered archaic and literary expression. Since roughly second half of 20th century, čaj is used for "tea" in Czech language, see the following tabletable (3).

(2)차(cha) is an alternative word for "tea" in Korean; see (4)

[edit] The derivatives from cha or chai

Language Name Language Name Language Name Language Name Language Name
Armenian tey Albanian çaj Amharic ሻይ shai Arabic شاي shāy Assamese saah Aramaic pronounced chai
Azerbaijani çay Bangla চা cha Bosnian čaj Bulgarian чай chai Capampangan cha
Cebuano tsa Croatian čaj Czech čaj (2) English char, slang Georgian ჩაი, chai
Greek τσάι tsái Gujarati ચા cha Hindi चाय chai Ilocano tsa-a, or i-tsa Japanese 茶, チャ, cha
Kannada ಚಹಾ Chaha Kazakh шай shai Kyrgyz чай, chai Khasi sha Konkani cha Korean 茶,차, cha(4)
Macedonian чај, čaj Malayalam "chaaya" Marathi चहा chahaa Mongolian цай, tsai Nepali chiya चिया
Oriya cha Pashto چای chai Persian چای chai Punjabi ਚਾਹ chah Portuguese chá
Romanian ceai Russian чай, chai Serbian чај, čaj Slovak čaj Slovene čaj
Somali shaah Swahili chai Sylheti saah Tagalog tsaa Thai ชา, cha
Tibetan ཇ་ ja Tlingit cháayu Turkish çay Turkmen çay Ukrainian чай chai
Urdu چا ٔےchai Uzbek choy Vietnamese *trà and chè Tamil *theyneer and tee

(5)


  • (5) They are both direct derivatives of the Chinese 茶; the latter term is used mainly in the north and describes a tea made with freshly-picked leaves.

The Polish word for a tea-kettle is czajnik, which could be derived directly from cha or from the cognate Russian word. However, tea in Polish is herbata, which, as well as Lithuanian arbata, was derived from the Latin herba thea, meaning "tea herb".

It is tempting to correlate these names with the route that was used to deliver tea to these cultures, although the relation is far from simple at times. As an example, the first tea to reach Britain was traded by the Dutch from Fujian, which uses te, and although later most British trade went through Canton, which uses cha, the Fujianese pronunciation continued to be the more popular.

In Ireland, or at least in Dublin, the term cha is sometimes used for "tea", as is pre-vowel-shift pronunciation "tay" (from which the Irish Gaelic word "tae" is derived). Char was a common slang term for tea throughout British Empire and Commonwealth military forces in the 19th and 20th centuries, crossing over into civilian usage.

The British English slang word "char" for "tea" arose from its Mandarin Chinese pronunciation "cha" with its spelling affected by British English arhotic dialect pronunciation.[46]

In North America, the word chai is used to refer almost exclusively to the Indian masala chai (spiced tea) beverage.

The original pronunciation "cha" in the Cantonese and Mandarin languages has no [j] ending. Therefore it is merely an adaptation of the Mandarin and Cantonese word "cha" in mainly Eurasian languages that do not usually tolerate a syllable that openly ends in "[a]".[citation needed] The different articulations of the word for tea into the two main groups: "teh-derived" (Min Chinese dialects) and "cha-derived" (Mandarin, Cantonese and other non-Min Chinese dialects) is an interesting one, as it reveals the particular Chinese local cultures where non-Chinese nations acquired their tea and "tea cultures". Not surprisingly, India and the Arab world most likely got their tea cultures from the Cantonese or the Southwestern Mandarin speakers, whereas the Russians got theirs from the northern Mandarin speakers. The Portuguese, the first Europeans to import the herb in large amounts, took the Cantonese form "chá", as used in their trading posts in the south of China, especially Macau. Conversely, other Western Europeans who copied the Min articulation "teh" probably traded with the Hokkienese while in Southeast Asia.

Quite recently, no earlier than 1980, "chai" entered North American English with a particular meaning: Indian masala black tea. Of course this is not the case in other languages, where "chai" usually just means black tea (as people traditionally drink more black tea than green outside of East Asia). English is thus one of the few languages that allow for the dual articulations of "tea" into a "teh-derived" word and a "cha-derived" one, such as Moroccan colloquial Arabic (Darija): in the case of Moroccan Arabic, "ash-shay" means "generic, or black Middle Eastern tea" whereas "atay" means a specialty tea: Zhejiang or Fujian green tea with fresh mint leaves. The Moroccans are said to have acquired a unique penchant in the Arab world for East Chinese green tea after the ruler Mulay Hassan exchanged some European hostages captured by the Barbary Pirates for a whole ship of Chinese tea. They have thus acquired a word for this special tea different from the generic "ash-shay". See Moroccan tea culture

Perhaps the only place in which a word unrelated to tea is used to describe the beverage is South America (particularly Andean countries), because a similar stimulant beverage, yerba mate, was consumed there long before tea arrived.

[edit] Tea culture

Main article: Tea culture

In many cultures, tea is often had at high class social events, such as afternoon tea and the tea party. It may be consumed early in the day to heighten alertness; it contains theophylline and bound caffeine[3] (sometimes called "theine"), although there are also decaffeinated teas. In many cultures such as Arab culture tea is a focal point for social gatherings. Moreover, the history of tea in Iran - in the Persian culture- is another to explore. One source cites: "the first thing you will be offered when a guest at an Iranian household is tea".[47]

There are tea ceremonies which have arisen in different cultures, Japan's complex, formal and serene one being one of the most well known. Other examples are the Chinese tea ceremony which uses some traditional ways of brewing tea. One form of Chinese tea ceremony is the Gongfu tea ceremony, which typically uses small Yixing clay teapots and oolong tea.

The American poet Wallace Stevens, a tea-fancier, is credited by Eleanor Cook with a "delicately implicit trope of drinking tea as a metaphor for reading (ingesting a drink from leaves)."[48] See for instance his "Tea".

[edit] Preparation

For a more detailed treatment of tea preparation and serving habits, particularly in non-Western countries, see Tea culture.
Korean tea kettle over hot coal

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

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

The best temperature for brewing tea depends on its type. Teas that have little or no oxidation period, such as a green or white tea, are best brewed at lower temperatures between 60 °C and 85 °C (140-185 °F), while teas with longer oxidation periods should be brewed at higher temperatures around 100 °C (212 °F).[49] The higher temperatures are required to extract the large, complex, flavorful phenolic molecules found in fermented tea, although boiling the water reduces the amount of dissolved oxygen in the water.

Tea Type Water Temp. Steep Time Infusions
White Tea 150F - 160F 1-2 minutes 3
Yellow Tea 160F - 170F 1-2 minutes 3
Green Tea 170F - 180F 1-2 minutes 4-6
Oolong Tea 180F - 190F 2-3 minutes 4-6
Black Tea 190F - 200F 2-3 minutes 2-3
Pu-her Tea 200F - 210F Limitless Several
Herbal Tea 210F 3-6 minutes Varied

[50]

Some tea sorts are often brewed several times using the same tea leaves. Historically, in China, tea is divided into a number of infusions. The first infusion is immediately poured out to wash the tea, and then the second and further infusions are drunk. The third through fifth are nearly always considered the best infusions of tea, although different teas open up differently and may require more infusions of hot water to bring them to life.[51]

One way to taste a tea, throughout its entire process, is to add hot water to a cup containing the leaves and after about 30 seconds to taste the tea. As the tea leaves unfold (known as "The Agony of the Leaves") they give up various parts of themselves to the water and thus the taste evolves. Continuing this from the very first flavours to the time beyond which the tea is quite stewed will allow an appreciation of the tea throughout its entire length.[52]

Black tea infusion.

[edit] Black tea

The water for black teas should be added at boiling point (100 °C or 212 °F). Many of the active substances in black tea do not develop at temperatures lower than 90 °C. For some more delicate teas lower temperatures are recommended. The temperature will have as large an effect on the final flavor as the type of tea used. The most common fault when making black tea is to use water at too low a temperature. Since boiling point drops with increasing altitude, this makes it difficult to brew black tea properly in mountainous areas. It is also recommended that the teapot be warmed before preparing tea, easily done by adding a small amount of boiling water to the pot, swirling briefly, before discarding. Black teas are usually brewed for about 4 minutes and should not be allowed to steep for less than 30 seconds or more than about five minutes (a process known as brewing or mashing in the UK, specifically in Yorkshire [53]). Longer steeping times make the tea bitter (at this point it is referred to as being stewed in the UK). When the tea has brewed long enough to suit the tastes of the drinker, it should be strained while serving. The popular varieties of black tea include the Assam tea, the Darjeeling tea and the black Ceylon tea.

[edit] Green tea

Water for green tea, according to most accounts, should be around 80 °C to 85 °C (176 °F to 185 °F); the higher the quality of the leaves, the lower the temperature. Hotter water will burn green-tea leaves, producing a bitter taste. Preferably, the container in which the tea is steeped, the mug, or teapot should also be warmed beforehand so that the tea does not immediately cool down. High-quality green and white teas can have new water added as many as five or more times, depending on variety, at increasingly high temperatures. Recently, green tea (as well as some black teas) have been shown to significantly increase interferon levels in tea consumers, which lends credence to the theory that some teas help boost the immune system.[54]

[edit] Oolong tea (or Wulong)

Oolong teas should be brewed around 90 °C to 100 °C (194 °F to 212 °F), and again the brewing vessel should be warmed before pouring in the water. Yixing purple clay teapots are the traditional brewing vessel for oolong tea. For best results use spring water, as the minerals in spring water tend to bring out more flavor in the tea. High quality oolong can be brewed multiple times from the same leaves, and unlike green tea it improves with reuse. It is common to brew the same leaves three to five times, the third steeping usually being the best.

[edit] Premium or delicate tea

Some teas, especially green teas and delicate Oolong teas, are steeped for shorter periods, sometimes less than 30 seconds. Using a tea strainer separates the leaves from the water at the end of the brewing time if a tea bag is not being used. However black Darjeeling tea, the 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.

[edit] Pu-erh tea (or Pu'er)

Pu-erh teas require boiling water for infusion. Some prefer to quickly rinse pu-erh for several seconds with boiling water to remove tea dust which accumulates from the aging process. Infuse pu-erh at the boiling point (100 °C or 212 °F), and allow to steep for 30 seconds or up to five minutes.

[edit] Serving

In order to preserve the pre-tannin tea without requiring it all to be poured into cups, a second teapot may be employed. 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 that the tea should not be stirred around while it is steeping (sometimes called winding 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.

[edit] Adding milk to tea

Tea is sometimes taken with milk

The addition of milk to tea was first mentioned in 1680 by the epistolist Madame de Sévigné.[55] Many teas are traditionally drunk with milk. These include Indian masala chai, and British tea blends. These teas tend to be very hearty varieties which can be tasted through the milk, such as Assams, or the East Friesian blend. Milk is thought to neutralize remaining tannins and reduce acidity.[56][57] The Chinese do not usually drink milk with tea (or indeed use milk at all) but the Manchurians do, and the elite of the Manchu Dynasty continued to do so. Hong Kong-style milk tea is based on British colonial habits.

The order of steps in preparing a cup of tea is a much-debated topic. Some say that 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.[58] Others insist that it is better to add the milk after brewing the tea, as most teas need to be brewed as close to boiling as possible. The addition of milk chills the beverage during the crucial brewing phase, meaning that the delicate flavor of a good tea cannot be fully appreciated. By adding the milk afterwards, it is easier to dissolve sugar in the tea and also to ensure that the desired amount of milk is added, as the color of the tea can be observed.[citation needed]

Moroccan tea being served. It is poured from a distance to produce a foam on the tea.

A 2007 study published in the European Heart Journal found that certain beneficial effects of tea may be lost through the addition of milk.[59]

[edit] Other additives

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.

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

Tea can also be fortified by the addition of alcohol, such as whisky or brandy.

The flavor of the tea can also be altered by pouring it from different heights, resulting in varying degrees of oxidization. The art of high-altitude pouring is used principally by people in Northern Africa (e.g. Morocco), but also in West Africa (e.g. Guinea, Mali, Senegal) and can positively alter the flavor of the tea, but it is more likely a technique to cool the beverage destined to be consumed immediately. In certain cultures the tea is given different names depending on the height it is poured from. In Mali, gunpowder tea is served in series of three, starting with the highest oxidization or strongest, unsweetened tea (cooked from fresh leaves), locally referred to as "bitter as death". Follows 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", informal social gathering that cuts across social and economic lines, starting in front of family compound gates in the afternoons, extending late in the night, and widely popular in Bamako and other large urban areas.

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

[edit] Economics of tea

Percentage of total global tea production by country or region in 2003
See also: List of countries by tea consumption per capita

Tea is the most popular drink in the world in terms of consumption. Its consumption equals all other manufactured drinks in the world — including coffee, chocolate, soft drinks, and alcohol — put together.[2] Most tea consumed outside East Asia is produced on large plantations in India or Sri Lanka, and is destined to be sold to large businesses. Opposite this large-scale industrial production there 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[43] although the per capita consumption of tea remains a modest 750 grams per person every year.

[edit] Statistics

Percentage of total tea production in 2003 Tea not grown in significant quantities Less than 5%. From 5 to 10%. More than 10%

[edit] Production

In 2003, world tea production was 3.15 million tonnes annually. The largest producer was India, followed by China (the order has since reversed), followed by Kenya and Sri Lanka. China is the only country today to produce in industrial quantities all different kinds of tea (white tea, yellow tea, green tea, blue-green tea, red tea and black tea).[citation needed]

Production in tonnes. Figures for 2004-2005
Data from de FAOSTAT (FAO) FAO database, accessed June 11, 2008
Country 2004 % 2005 %
China 855,422 25 % 953,660 27 %
India 857,000 25 % 830,750 23 %
Kenya 324,600 9 % 328,500 9 %
Sri Lanka 308,090 9 % 317,200 9 %
Turkey 201,663 6 % 217,520 6 %
Indonesia 171,200 5 % 177,700 5 %
Vietnam 119,500 3 % 132,525 3 %
Japan 100,700 3 % 100,000 3 %
Argentina 70,389 2 % 67,871 2 %
Bangladesh 57,580 2 % 57,580 2 %
Iran 40,250 2 % 59,180 2 %
Malawi 50,090 1 % 38,000 1 %
Uganda 35,706 1 % 37,734 1 %
Other countries 208,949 6 % 215,940 6 %
Total 3,401,088 100 % 3,550,194 100 %

[edit] Tea production certification

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

Production of organic tea is rising; 3,500 tonnes of organic tea were grown in 2003. The majority of this tea (about 75%) is sold in France, Germany, Japan, the United Kingdom and the United States.

[edit] Trade

Evolution of the average price of tea since 1989

[edit] Export

The amount of tea produced is rising but exports are declining. In 2003, 1.4 million tonnes of tea were exported, a decline of 2.6% compared to 2002. This is primarily due to the strong drop in exports from India and Indonesia.

[edit] Import

The principal importers are the CIS, the EU, Pakistan, the United States, Egypt and Japan. In 2003, 1.39 million tons were imported – an increase of 1% over 2002.

[edit] Prices

The large quantities produced in 2003 did not greatly affect the prices, which were relatively stable in that year.

[edit] Packaging

[edit] Tea bags

Tea Bags

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

Tea leaves are packed into a small envelope(usually paper).[citation needed] tea bag. It is easy and convenient, making tea bags popular for many people today. However, the tea used in tea bags has an industry name - it is called fannings or "dust" and is the waste product produced from the sorting of higher quality loose leaf tea.[citation needed] It is commonly held among tea aficionados that this method provides an inferior taste and experience. The paper used for the bag can also be tasted by many, which can detract from the tea's flavor. Because fannings and dust are a lower quality of the tea to begin with, the tea found in tea bags is less finicky when it comes to brewing time and temperature.

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

  • Dried tea loses its flavor quickly on exposure to air. Most bag teas (although not all) contain leaves broken into small pieces; the great surface area to volume ratio of the leaves in tea bags exposes them to more air, and therefore causes them to go stale faster. Loose tea leaves are likely to be in larger pieces, or to be entirely intact.
  • Breaking up the leaves for bags extracts flavored oils.
  • The small size of the bag does not allow leaves to diffuse and steep properly.
  • Some tea bags are made using a wet paper strength-reinforcing coating using epichlorohydrin, a known carcinogen.

[edit] Pyramid tea bags

Pyramid tea bag

The "pyramid tea bag", introduced by Lipton[60] and PG Tips in 1996[61], has a unique design that addresses one of connoisseurs' arguments against paper tea bags, because its three-dimensional tetrahedron shape allows more room for tea leaves to expand while steeping. However, some types of pyramid tea bags have been criticized as being environmentally unfriendly, since their synthetic material does not break down in landfills as loose tea leaves and paper tea bags do.[62]

[edit] Loose tea

Loose-leaf tea

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

[edit] Compressed tea

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

[edit] Instant tea

In recent times, "instant teas" are becoming popular, similar to freeze dried instant coffee. Instant tea was developed in the 1930s, but not commercialized until the late 1950s, and is only more recently becoming popular. These products often come with added flavors, such as vanilla, honey or fruit, and may also contain powdered milk. Similar products also exist for instant iced tea, due to the convenience of not requiring boiling water. Tea connoisseurs tend to criticize these products for sacrificing the delicacies of tea flavor in exchange for convenience.

[edit] Canned tea

Canned tea was first launched in 1981 in Japan. As such, it is a fairly recent innovation, and it has mostly benefits in marketing.

[edit] Storage

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

When storing green tea, discreet use of refrigeration or freezing is recommended. In particular, drinkers need to take precautions against temperature variation.[63]

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

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

[edit] See also

[edit] References

[edit] Specific references

  1. ^ Webster's Third New International Dictionary
  2. ^ a b Alan Macfarlane; Iris Macfarlane (2004). The Empire of Tea. The Overlook Press. pp. 32. ISBN 1-58567-493-1.
  3. ^ a b Penelope Ody, (2000). Complete Guide to Medicinal Herbs. New York, NY: Dorling Kindersley Publishing. pp. 48. ISBN 0-7894-6785-2.
  4. ^ Four Types of Tea
  5. ^ Tea types and tea varieties
  6. ^ Dictionary.com search Herbal tea URL accessed February 15, 2007.
  7. ^ Telegraph Online, 17 Sept 2005. http://www.telegraph.co.uk/gardening/main.jhtml?xml=/gardening/2005/09/17/gtea17.xml
  8. ^ Rolfe, Jim; Yvonne Cave (2003). Camellias: A Practical Gardening Guide. Timber Press. ISBN 0881925772.
  9. ^ Pruess, Joanna (2006). Tea Cuisine: A New Approach to Flavoring Contemporary and Traditional Dishes. Globe Pequot. ISBN 1592287417.
  10. ^ Elizabeth S. Hayes (1980). Spices and Herbs: Lore and Cookery. Courier Dover Publications. pp. 74. ISBN 0486240266. http://books.google.com/books?id=htsIVCwRsEcC&dq=. Retrieved on 2008-09-20.
  11. ^ Britannica Tea Cultivation URL accessed June, 2007.
  12. ^ a b Mondal 2007, p. 519
  13. ^ Liu Tong (2005). Chinese tea. Beijing: China Intercontinental Press. pp. 137. ISBN 7-5085-0835-1.
  14. ^ Wonders of Tea - Which Tea is Healthiest?
  15. ^ Journal of Nutrition - Antioxidant Activity of Black Tea vs. Green Tea
  16. ^ http://www.webcitation.org/query?url=http%3A%2F%2Fwww.ars.usda.gov%2FSP2UserFiles%2FPlace%2F12354500%2FData%2FORAC%2FORAC07.pdf&date=2009-05-23 Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods – 2007
  17. ^ Bennett Alan Weinberg and Bonnie K. Bealer (2001). The World of Caffeine: The Science and Culture of the World's Most Popular Drug. Routledge. pp. 228. ISBN 0415927226. http://books.google.com/books?id=YdpL2YCGLVYC&dq=. Retrieved on 2008-09-20.
  18. ^ M. B. Hicks, Y-H. P. Hsieh, L. N. Bell, Tea preparation and its influence on methylxanthine concentration, Food Research International 29(3-4) 325-330 (1996)
  19. ^ Graham H. N.; Green tea composition, consumption, and polyphenol chemistry; Preventive Medicine 21(3):334-50 (1992)
  20. ^ [1]
  21. ^ http://www.stashtea.com/caffeine.htm
  22. ^ Yamamoto, Kim & Juneja 1997:4 "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 (2n=30) and can be easily hybridized 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."
  23. ^ Fuller, Thomas (2008-04-21). "A Tea From the Jungle Enriches a Placid Village". The New York Times (New York: The New York Times Company): p. A8. http://www.nytimes.com/2008/04/21/world/asia/21tea.html.
  24. ^ The Oldest Tea Tree on the Earth, (Kunming, 2006).
  25. ^ Chow p. 19-20 (Czech edition); also Arcimovicova p. 9, Evans p. 2 and others
  26. ^ Lu Ju p. 29-30 (Czech edition)
  27. ^ Chinese green tea health benefits
  28. ^ Chow p. 20-21
  29. ^ Evans p. 3
  30. ^ a b "Tea". Encarta. http://encarta.msn.com/encyclopedia_761563182/Tea.html. Retrieved on 2008-07-23.
  31. ^ "Tea". The Columbia Encyclopedia Sixth Edition. 2001-07. http://www.bartleby.com/65/te/tea.html. Retrieved on 2008-07-23.
  32. ^ George Staunton (1797). An Historical Account of the Embassy to the Emperor of China, Undertaken By Order of the King of Great Britain; Including the Manners and Customs of the Inhabitants; and Preceded By an Account of the Causes of the embassy and Voyage to China. J. Stockdale. pp. 452. "The Chinese perceiving these dispositions in the monkey took advantage of the propensities of the animal and converted them to life in a domestic state which in that of nature were exerted to their annoyance."
  33. ^ Robert Fortune (1852). A Journey to the Tea Countries of China; including Sung-Lo and the Bohea Hills. J. Murray. pp. 237. "I should not like to assert that no tea is gathered on these hills by the agency of chains and monkeys but I think it may be safely affirmed that the quantity in such is small."
  34. ^ Constance Frederica Gordon Cumming. Wanderings in China. W. Blackwood and Sons. pp. 318.
  35. ^ Laura C. Martin (2007). Tea: The Drink that Changed the World. Tuttle Publishing. pp. 133. ISBN 0804837244.
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[edit] General references

[edit] External links

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