Tea is a beverage made by steeping processed leaves, buds, or twigs of the tea bush (Camellia sinensis) in hot water for a few minutes. The processing can include oxidation (fermentation), heating, drying, and the addition of other herbs, flowers, spices, and fruits.
There are four basic types of true tea: black tea, oolong tea, green tea, and white tea. The term "herbal tea" usually refers to infusions of fruit or of herbs (such as rosehip, chamomile, or jiaogulan) that contain no C. sinensis. (Alternative terms for herbal tea that avoid the word "tea" are tisane and herbal infusion.) This article is concerned exclusively with preparations and uses of the tea plant C. sinensis.
Tea is a natural source of methylxanthines such as caffeine [1], catechins, and theanine. It has almost no carbohydrates, fat, or protein. It has a cooling, slightly bitter and astringent taste.
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The types of tea are distinguished by their processing. Leaves of Camellia sinensis, if not dried quickly after picking, soon begin to wilt and oxidize. The leaves turn progressively darker, as chlorophyll breaks down and tannins are released. The next step in processing is to stop the oxidation process at a predetermined stage by deactivating the enzymes responsible by heating, which in black tea is done simultaneously with drying.
The term fermentation is still used in tea process to describe this process, even though no true fermentation happens (i.e., the process is not driven by microorganisms).However without careful moisture and temperature control during its manufacture and life thereafter, fungi will grow on tea. This form of fungi causes real fermentation that will contaminate the tea with toxic and sometimes carcinogenic substances as well as off-flavours, so that tea must be discarded.
Tea is traditionally classified based on the degree or period of "fermentation" (actually enzymatic oxidation) the leaves have undergone[2][3][4]:
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 |
Almost all teas in bags and most other teas sold in England are blends. Blending may occur at the level of tea-planting area (e.g., Assam), or teas from many areas may be blended. The aim of blending is a stable taste over different years, and a better price. More expensive, better tasting tea may cover the inferior taste of cheaper tea.
There are various teas which have additives and/or different processing than "pure" varieties. Tea is able to easily receive any aroma, which may cause problems in processing, transportation or storage of tea, but can be also advantageously used to prepare scented teas.
Tea contains catechins, a type of antioxidant. In fresh tea leaf, catechins can be up to 30% of the dry weight. Catechins are highest in concentration in white and green teas while black tea has substantially less due to its oxidative preparation. Tea contains the stimulant caffeine at about 3% of the dry weight, translating to between 30mg and 90mg per 8oz cup depending on type and brand [6] and brewing method[7]. Tea also contains small amounts of theobromine and theophylline[8]. Tea also contains fluoride, with certain types of brick tea made from old leaves and stems having the highest levels. [9] Regular drinking of tea can prevent dental cavity to some extent[citation needed]. However, excessive consumption of tea (brick tea in particular) has led to cases of fluorosis.[10][11]. Finally, as a dried plant, tea preserves some vitamins and played an important role in keeping Chinese sailors' health in history, such as the voyage led by Zheng He[citation needed].
The cradle of the tea plant is a region that encompasses eastern and southern China, northern Myanmar, and Assam in northeastern India. Spontaneous (wild) growth of the assamica variant is observed in an area ranging from the Indian state of Assam to the Chinese province Yunnan and the northern part of Myanmar. The variant sinensis grows naturally in eastern and southeastern regions of China.[12] Recent studies and occurrence of hybrids of the two types in wider area extending over mentioned regions suggest the place of origin of the Camellia sinensis variant is in an area consisting of the northern part of Myanmar and the Yunnan and Sichuan provinces of China.[13]
Origins of human use of tea are described in several myths, but it is unknown as to where tea was first created as a drink.
In one popular Chinese legend, Shennong, the legendary Emperor of China, inventor of agriculture and Chinese medicine, was on a journey about five thousand years ago. The Emperor, known for his wisdom in the ways of science, believed that the safest way to drink water was by first boiling it. One day he noticed some leaves had fallen into his boiling water. The ever inquisitive and curious monarch took a sip of the brew and was pleasantly surprised by its flavour and its restorative properties. Variant of the legend tells that the emperor tried medical properties of various herbs on himself, some of them poisonous, and found tea works as an antidote.[14] Shennong is also mentioned in Lu Yu's Cha Jing, famous early work on the subject.[15]
A Chinese legend, which spread along with Buddhism, the Indian Bodhidharma is credited with discovery of tea. Bodhidharma, a semi-legendary Buddhist monk, founder of the Chan school of Buddhism, journeyed to China. He became angered because he was falling asleep during meditation, so he cut off his eyelids. Tea bushes sprung from the spot where his eyelids hit the ground.[16] Sometimes, the second story is retold with Gautama Buddha in place of Bodhidharma[17] In another variant of the first mentioned myth, Gautama Buddha discovered tea when some leaves had fallen into boiling water.[18]
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 symbol of status. It is not surprising its discovery is ascribed to religious or royal origins.
The Chinese have enjoyed tea for centuries if not millennia. While historically the origin of tea as a medicinal herb useful for staying awake is unclear, China is considered to have the earliest records of tea drinking, with recorded tea use in its history dating back to the first millennium BC. The Han Dynasty used tea as medicine. The use of tea as a beverage drunk for pleasure on social occasions dates from the Tang Dynasty or earlier.
The Tang Dynasty writer Lu Yu's 陸羽 (AC729-804) Cha Jing 茶經 is an early work on the subject. (See also Tea Classics) According to Cha Jing writing, around AC760, 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.
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 favoured by the 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.
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.
In 17th century China numerous advances were made in tea production. In the southern part of China, tea leaves were sun dried and then half fermented, producing Black Dragon teas or Oolongs. However, this method was not common in the rest of China.
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. These terms are not found in other countries. 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.
The earliest known references to green tea in Japan are in a text written by a Buddhist monk in the 9th century. 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 Saicho (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 Yojoki (喫茶養生記; how to stay healthy by drinking tea) was written by Eisai. 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 modern tea ceremony developed over several centuries by Zen Buddhist monks under the original guidance of the monk Sen-no Rikyu (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 (Japanese: 煎茶), which is an unfermented form of green tea. In 1835, Kahei Yamamoto developed gyokuro (Japanese: 玉露), 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.
As the Venetian explorer Marco Polo failed to mention tea in his travel records, it is conjectured that the first Europeans to encounter tea were either Jesuits living in Beijing who attended the court of the last Ming Emperors, or Portuguese explorers visiting Japan in 1560. Russia discovered tea in 1618 after a Ming Emperor of China offered it as a gift to Czar Michael I.
Soon imported tea was introduced to Europe, where it quickly became popular among the wealthy in France and the Netherlands. English use of tea dates from about 1650 and is attributed to Catherine of Braganza (Portuguese princess and queen consort of Charles II of England).
The high demand for tea in Britain caused a huge trade deficit with China, leading the British to try to produce their own in the mid-nineteenth century. Using seeds smuggled from China (there was an official ban on foreigners entering tea-growing areas), the British went through some failed experiments but finally succeeded in setting up productive plantations in parts of colonial India with suitable climates and soil[19][20]. This created the modern tea industries of Assam tea, Ceylon tea, Darjeeling tea, and Nilgiri tea. The British also tried to balance the trade deficit by selling opium to the Chinese, which later led to the First Opium War in 1838–1842.
The Boston Tea Party was an act of uprising in which Boston residents destroyed crates of British tea in 1773, in protest against British tea and taxation policy. Prior to the Boston Tea Party, residents of Britain's North American 13 colonies drank far more tea than coffee. In Britain, coffee was more popular. After the protests against the various taxes, British Colonists stopped drinking tea as an act of patriotism. Similarly, Britons slowed their consumption of coffee.
Iced Tea has been popular in North America since the 1904 St. Louis World's Fair.
These days, contradicting tea economies do exist. Tea farmers in Japan, Taiwan and China often enjoy better incomes compared to farmers in black tea producing countries.
Tea is now being grown at Tregothnan in Cornwall in England: [5].
Several health benefits have been claimed and some are supported by independent research.
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. One is te (Taiwanese tê) which comes from the Min Nan dialect spoken around the port of Xiamen (Amoy). 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. Yet another different pronunciation is zu, used in the Wu dialect spoken around Shanghai.
Languages that have te derivatives include Afrikaans (tee), Armenian, Catalan (te), Czech (té or thé, but these words sound archaic; čaj is used nowadays, as explained in the next paragraph), 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/ or /tei/), Hungarian (tea), Icelandic (te), Indonesian (teh), Irish (tae), Italian (tè), scientific Latin (thea), Latvian (tēja), Malay (teh), Norwegian (te), Polish (herbata from Latin herba thea), Scots Gaelic (tì, teatha), Singhalese, Spanish (té), Swedish (te), Tamil (thè), Welsh (te), and Yiddish (טיי, /tei/).
Those that use cha or chai derivatives include Albanian (çaj), Arabic (شَاي /shai/), Assyrian (pronounced chai), Azeri: (çay), Bengali (চা), Bosnian (čaj), Bulgarian (чай), Capampangan (cha), Cebuano (tsa), Croatian (čaj), Czech (čaj), Greek (τσάι), Gujarati (cha), Hindi (चाय chai), Japanese (茶, ちゃ, cha), Kazakh (шай), Korean (차), Macedonian (čaj), Malayalam, Nepali (cheeya), Persian (چاى), Punjabi (ਚਾਹ), Portuguese (chá), Romanian (ceai), Russian, (чай, chai), Serbian (чај), Slovak (čaj), Slovene (čaj), Somali (shaax), Swahili (chai), Tagalog (tsaa), Thai (ชา), Tibetan (ja), Turkish (çay), Ukrainian (чай), Urdu (چاى), Uzbek (choy) and Vietnamese (trà and chè are both direct derivatives of the Chinese 茶; the latter term is used mainly in the north and depicts 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 was probably 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", with "tay" as a common pronunciation throughout the land (derived from the Irish Gaelic tae), and 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.
In North America, the word chai is used to refer almost exclusively to the Indian chai (or masala chai) beverage.
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, hierba mate, was consumed there long before tea arrived. In various places of South America, any tea is referred to as mate.
Tea is often drunk at social events, such as afternoon tea and the tea party. It may be drunk early in the day to heighten alertness; it contains theophylline and bound caffeine (sometimes called "theine"), although there are also decaffeinated teas.
There are tea ceremonies which have arisen in different cultures, Japan's complex, formal and serene one being the most known. Other examples are the Korean tea ceremony or some traditional ways of brewing tea in Chinese tea culture.
This section describes the most widespread method of making tea. Completely different methods are used in North Africa, Tibet and perhaps in other places. In the American South, iced tea is also prepared differently.
The way to prepare tea is usually thought to be with loose tea placed either directly in a teapot or contained in a tea infuser, rather than a teabag. However, perfectly acceptable tea can be made with teabags. Some circumvent the teapot stage altogether and brew the tea directly in a cup or mug. This method is becoming more popular. For an acceptable quality, however, it is necessary to obey the rules for preparation such as sufficient infusion time by placing the teabag in the cup before pouring the hot water.
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 boiling water to bring them to life.
Typically, the best temperature for brewing tea can be determined by its type. Teas that have little or no oxidation period, such as a green or white tea, are best brewed at lower temperatures around 80 °C, while teas with longer oxidation periods should be brewed at higher temperatures around 100 °C [21][22].
The amount of tea to be used per amount of water is obviously of critical importance, yet is the subject of some confusion. One reason is to do with knowledge in popular culture (one spoon per person and one for the pot etc),another to do with the varying nature and quality amongst different teas and within the same garden from season to season. One basic recipe may be one slightly heaped teaspoon of tea (about 5mLs) for each 200mLs of water prepared as above. This may be varied acording to tea and taste, with a stronger Assam to be drunk with milk prepared with more leaf, and a more delicate high grown tea such as a Darjeeling prepared with a little less (as the stronger mid-flavours will overwhelm the champagne notes). For tea, as with many such things, there is no right or wrong answer, only the quest for perfection. Another 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 ("the Agony of the Leaves") it gives up various parts of itself 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.
During World War II, tea was rationed. In 1953 (after rationing ended), Tetley launched the tea bag to the UK and it was an immediate success. The convenience of the tea bag revolutionized how Britons drank their tea and now the traditional tea pot has given way to making tea in a cup using a tea bag.
Tea leaves are packed into a small (usually paper) 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. 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 flavour. 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-flavoured include:
A relative newcomer to the market, the "triangle tea bag" has an unusual design that addresses two of connoisseurs' arguments against paper tea bags. Its three-dimensional, pyramidal shape allows more room for tea leaves to expand while steeping, and because the bags are made of nylon mesh, they do not leave flavours (such as paper) in the tea. These characteristics let the delicate flavors of gourmet selections (such as white teas) shine through; however, the bags have been criticized as being environmentally irresponsible, since the synthetic material does not break down in landfills as loose tea leaves and paper tea bags do. [citation needed]
The tea leaves are packaged loosely in a canister or other container. Rolled gunpowder tea leaves, that resists 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 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.
A lot of tea is still compressed for storage and aging convenience. Commonly Pu-Erh tea is compressed and then drunk by loosening leaves off using a small knife. Most of the time compressed tea can be stored longer than loose leaf tea.
One of the more modern forms of tea consumption, an alternative to the tea bag, is tea sticks. Currently, Serengeti Tea Company manufactures a tea stick named Ticolino. Ticolino are dubbed as single serving tea sticks which use an infusing technology to brew the tea leaves inside, releasing the flavour and aroma.
In recent times, "instant teas" are becoming popular, similar to freeze dried instant coffee. Instant tea was developed in the 1930's, but not commercialized until the late 1950's, and is only more recently becoming popular. These products often come with added flavours, 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 criticise these products for sacrificing the delicacies of tea flavour in exchange for convenience.
This latest method of marketing tea was first launched in 1981 in Japan.
Tea storage is essential to keeping the taste of tea pure. Tea absorbs moisture and odours very easily so it is necessary to keep it in some kind of container away from strong odours. One way to store a small amount of loose leaf tea is to keep it in a tin or glass container. These containers will keep the tea free from moisture and also keep odours out so the tea will keep its original flavour. Other ways to store tea include air tight bags. When storing the tea keep it away from sun light, strong odours, and moisture. For larger amounts of tea it would be good to put it into a cooler type of container. First wrap the tea in brown paper then wrap the paper again with brown paper to keep out any moisture. Then place the tea into a cooler that has nothing in and has a good seal. Next take the tea to a cool place away from moisture and odours. The length of time you can store tea depends on its type. Some teas such as flower teas will go bad in a month or so, but others may get better with age.