Camellia sinensis | |
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Camellia sinensis foliage | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Ericales |
Family: | Theaceae |
Genus: | Camellia |
Species: | C. sinensis |
Binomial name | |
Camellia sinensis | |
Native range of Camellia sinensis | |
Synonyms [2] | |
Camellia sinensis
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Camellia sinensis is a species of evergreen shrub or small tree in the flowering plant family Theaceae. Its leaves, leaf buds, and stems can be used to produce tea. Common names include tea plant, tea shrub, and tea tree (unrelated to Melaleuca alternifolia , the source of tea tree oil, or the genus Leptospermum commonly called tea tree).
White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all harvested from one of two major varieties grown today, C. sinensis var. sinensis and C. s. var. assamica, [3] but are processed differently to attain varying levels of oxidation with black tea being the most oxidized and white being the least. [4] Kukicha (twig tea) is also harvested from C. sinensis, but uses twigs and stems rather than leaves.
Camellia sinensis is native to East Asia, the Indian Subcontinent, and Southeast Asia, but it is today cultivated all around the world in tropical and subtropical regions. It is an evergreen shrub or small tree that is usually trimmed to below 2 m (6.6 ft) when cultivated for its leaves. It has a strong taproot. The flowers are yellow-white, 2.5–4 cm (0.98–1.57 in) in diameter, with seven or eight petals.
The seeds of C. sinensis and C. oleifera can be pressed to yield tea oil, a sweetish seasoning and cooking oil that should not be confused with tea tree oil, an essential oil that is used for medical and cosmetic purposes, and originates from the leaves of a different plant.
The leaves are 4–15 cm (1.6–5.9 in) long and 2–5 cm (0.79–1.97 in) broad. Fresh leaves contain about 4% caffeine, as well as related compounds including theobromine. [5] The young, light-green leaves are preferably harvested for tea production when they have short, white hairs on the underside. Older leaves are deeper green. Different leaf ages produce differing tea qualities, since their chemical compositions are different. Usually, the tip (bud) and the first two to three leaves are harvested for processing. This hand picking is repeated every one to two weeks.
In 2017, Chinese scientists sequenced the genome of C. s. var. assamica. [6] It contains about three billion base pairs, which was larger than most plants previously sequenced. [7]
The generic name Camellia is taken from the Latinized name of Rev. Georg Kamel, [8] SJ (1661–1706), a Moravian-born Jesuit lay brother, pharmacist, and missionary to the Philippines.
Carl Linnaeus chose his name in 1753 for the genus to honor Kamel's contributions to botany [9] (although Kamel did not discover or name this plant, or any Camellia, [10] and Linnaeus did not consider this plant a Camellia but a Thea). [11]
Robert Sweet shifted all formerly Thea species to the genus Camellia in 1818. [12] The name sinensis means "from China" in Latin.
Four varieties of C. sinensis are recognized. [2] Of these, C. sinensis var. sinensis and C. s. var. assamica (JW Masters) Kitamura are most commonly used for tea, and C. s. var. pubilimba Hung T. Chang and C. s. var. dehungensis (Hung T. Chang & BH Chen) TL Ming are sometimes used locally. [2] The Cambodia type tea (C. assamica subsp. lasiocaly) was originally considered a type of assam tea. However, later genetic work showed that it is a hybrid between Chinese small leaf tea and assam type tea. [13]
Tea plants are native to East Asia, and probably originated in the borderlands of north Burma and southwestern China. [14]
Chinese (small leaf) tea may have originated in southern China possibly with hybridization of unknown wild tea relatives. However, since no wild populations of this tea are known, the precise location of its origin is speculative. [15] [16]
Given their genetic differences forming distinct clades, Chinese Assam type tea (C. s. var. assamica) may have two different parentages – one being found in southern Yunnan (Xishuangbanna, Pu'er City) and the other in western Yunnan (Lincang, Baoshan). Many types of Southern Yunnan Assam tea have been hybridized with the closely related species Camellia taliensis. Unlike Southern Yunnan Assam tea, Western Yunnan Assam tea shares many genetic similarities with Indian Assam type tea (also C. s. var. assamica). Thus, Western Yunnan Assam tea and Indian Assam tea both may have originated from the same parent plant in the area where southwestern China, Indo-Burma, and Tibet meet. However, as the Indian Assam tea shares no haplotypes with Western Yunnan Assam tea, Indian Assam tea is likely to have originated from an independent domestication. Some Indian Assam tea appears to have hybridized with the species Camellia pubicosta. [15] [16]
Assuming a generation of 12 years, Chinese small leaf tea is estimated to have diverged from Assam tea around 22,000 years ago; this divergence would correspond to the last glacial maximum, [15] [16] while Chinese Assam tea and Indian Assam tea diverged 2,800 years ago.
Chinese small leaf type tea was introduced into India in 1836 by the British and some Indian Assam type tea (e.g. Darjeeling tea) appear to be genetic hybrids of Chinese small leaf type tea, native Indian Assam, and possibly also closely related wild tea species. [17]
Hundreds, [18] if not thousands of cultivars of C. sinensis are known. Some Japanese cultivars include:
Camellia sinensis is mainly cultivated in tropical and subtropical climates, in areas with at least 127 cm (50 in) of rainfall a year. Tea plants prefer a rich and moist growing location in full to part sun, and can be grown in hardiness zones 7–9. However, the clonal one is commercially cultivated from the equator to as far north as Cornwall and Scotland on the UK mainland. [21] [22] Many high quality teas are grown at high elevations, up to 2,200 m (7,200 ft), as the plants grow more slowly and acquire more flavor.
Tea plants will grow into a tree if left undisturbed, but cultivated plants are pruned to waist height for ease of plucking. Two principal varieties are used, the small-leaved Chinese variety plant (C. s. sinensis) and the large-leaved Assamese plant (C. s. assamica), used mainly for black tea.
The Chinese plant is a small-leafed bush with multiple stems that reaches a height of some 3 m (9.8 ft). It is native to southeast China. The first tea plant variety to be discovered, recorded, and used to produce tea dates back 3,000 years ago; it yields some of the most popular teas.
C. s. var. waldenae was considered a different species, C. waldenae by SY Hu, [23] but it was later identified as a variety of C. sinensis. [24] This variety is commonly called Waldenae Camellia. It is seen on Sunset Peak and Tai Mo Shan in Hong Kong. It is also distributed in the Guangxi province. [23]
Three main kinds of tea are produced in India:
Tea leaves are eaten by some herbivores, such as the caterpillars of the willow beauty (Peribatodes rhomboidaria), a geometer moth.
Although health benefits have been assumed throughout the history of using tea as a common beverage, no high-quality evidence shows that tea confers significant benefits. [25] [26] In clinical research over the early 21st century, tea has been studied extensively for its potential to lower the risk of human diseases, but none of this research is conclusive as of 2017. [25]
Caffeine, a molecule produced in C. sinensis, functions as a secondary metabolite and acts as a natural pesticide: it can paralyze and kill herbivorous insects feeding on the plant. [27] Caffeine is a purine alkaloid and its biosynthesis occurs in young tea leaves and is regulated by several enzymes. [28] [29] The biosynthetic pathway in C. sinensis is similar to other caffeine-producing plants such as coffee or guayusa. [30] Analysis of the pathway was carried out by harvesting young leaves and using reverse transcription PCR to analyze the genes encoding the major enzymes involved in synthesizing caffeine. The gene TCS1 encodes caffeine synthase. Younger leaves feature high concentrations of TCS1 transcripts, allowing more caffeine to be synthesized during this time. Dephosphorylation of xanthosine-5'-monophosphate into xanthosine is the committed step for the xanthosines entering the beginning of the most common pathway. A sequence of reactions turns xanthosine (9β-D-ribofuranosylxanthine) into 7-methylxanthosine, then 7-methylxanthine, then theobromine (3,7-dimethylxanthine), and finally into caffeine (1,3,7-trimethylxanthine).
Oolong is a traditional semi-oxidized Chinese tea produced through a process that includes withering the leaves under strong sun and allowing some oxidation to occur before curling and twisting. Most oolong teas, especially those of fine quality, involve unique tea plant cultivars that are exclusively used for particular varieties. The degree of oxidation, which is controlled by the length of time between picking and final drying, can range from 8% to 85% depending on the variety and production style. Oolong is especially popular in southeastern China and among ethnic Chinese in Southeast Asia, as is the Fujian preparation process known as the gongfu tea ceremony.
Tea is an aromatic beverage prepared by pouring hot or boiling water over cured or fresh leaves of Camellia sinensis, an evergreen shrub native to East Asia which probably originated in the borderlands of south-western China and northern Myanmar. Tea is also made, but rarely, from the leaves of Camellia taliensis. After plain water, tea is the most widely consumed drink in the world. There are many different types of tea; some have a cooling, slightly bitter, and astringent flavour, while others have profiles that include sweet, nutty, floral, or grassy notes. Tea has a stimulating effect in humans, primarily due to its caffeine content.
Herbal teas, technically known as herbal infusions, and less commonly called tisanes, are beverages made from the infusion or decoction of herbs, spices, or other plant material in hot water. Often herb tea, or the plain term tea, is used as a reference to all sorts of herbal teas. Many herbs used in teas/tisanes are also used in herbal medicine and in folk medicine.
Camellia is a genus of flowering plants in the family Theaceae. They are found in tropical and subtropical areas in eastern and southern Asia, from the Himalayas east to Japan and Indonesia. There are more than 220 described species; almost all are found in southern China and Indochina. Camellias are popular ornamental, tea, and woody-oil plants cultivated worldwide for centuries. Over 26,000 cultivars, with more than 51,000 cultivar names, including synonyms, have been registered or published.
Pu'er or pu-erh is a variety of fermented tea traditionally produced in Yunnan Province, China. In the context of traditional Chinese tea production terminology, fermentation refers to microbial fermentation, and is typically applied after the tea leaves have been sufficiently dried and rolled. As the tea undergoes controlled microbial fermentation, it also continues to oxidize, which is also controlled, until the desired flavors are reached. This process produces tea known as hēichá (黑茶), literally "black tea", though the term is commonly translated to English as "dark tea" to distinguish it from the English-language black tea, which it is not.
White tea may refer to one of several styles of tea which generally feature young or minimally processed leaves of the Camellia sinensis plant.
Theaceae, the tea family, is a family of flowering plants comprising shrubs and trees, including the economically important tea plant, and the ornamental camellias. It can be described as having from seven to 40 genera, depending on the source and the method of circumscription used. The family Ternstroemiaceae has been included within Theaceae; however, the APG III system of 2009 places it instead in Pentaphylacaceae. Most but not all species are native to China and East Asia.
Assam tea is a black tea named after Assam, India, the region of its production. It is manufactured specifically from the plant Camellia sinensis var. assamica (Masters). Assam's people tried to plant the Chinese varieties in Assam soil but did not succeed. Assam tea is now mostly grown at or near sea level and is known for its body, briskness, malty flavour, and strong, bright colour. Assam teas, or blends containing Assam tea, are often sold as "breakfast" teas. For instance, Irish breakfast tea, a maltier and stronger breakfast tea, consists of small-sized Assam tea leaves.
Nilgiri tea is a drink made by infusing leaves of Camellia sinensis that is grown and processed in the Nilgiris district in Tamil Nadu, India. The leaves are processed as black tea, though some estates have expanded their product offerings to include leaves suitable for making green, white and oolong teas. It is generally described as being a brisk, fragrant and full-bodied tea. The region produces both rolled and crush, tear, curl tea and it is predominantly used for blending. Nilgiri tea is also used for making iced tea and instant tea.
The history of tea spreads across many cultures throughout thousands of years. The tea plant Camellia sinensis is native probably originated in the borderlands of southwestern China and northern Myanmar. One of the earliest accounts of tea drinking is dated back to China's Shang dynasty, in which tea was consumed in a medicinal concoction. An early credible record of tea drinking dates to the 3rd century AD, in a medical text written by Chinese physician Hua Tuo. It first became known to the western world through Portuguese priests and merchants in China during the early 16th century. Drinking tea became popular in Britain during the 17th century. To compete with the Chinese monopoly on tea, the British East India Company introduced commercial tea production to British India.
Camellia japonica, known as common camellia, or Japanese camellia, is a species of Camellia, a flowering plant genus in the family Theaceae. There are thousands of cultivars of C. japonica in cultivation, with many colors and forms of flowers. Despite its common name, it is native to China, not Japan. The cultivation of Camellia japonica also started in China. Its widespread cultivation can be traced back to the Song Dynasty, when 15 varieties of Camellia japonica were recorded in literature. It was later introduced to Japan. It grows in forests, at altitudes of around 300–1,100 metres (980–3,600 ft).
Nepali tea is a beverage made from the leaves of tea plants grown in Nepal. They are distinctive in appearance, aroma and taste, but are similar in many ways to tea produced in Darjeeling, perhaps because the eastern zones of Nepal have geography and topography similar to Darjeeling. Its relatively smaller production quantities mean that teas from Nepal are less well known than those from Darjeeling.
Darjeeling tea is a tea made from Camellia sinensis var. sinensis that is grown and processed in Darjeeling district or Kalimpong district in West Bengal, India. Since 2004, the term Darjeeling tea has been a registered geographical indication referring to products produced on certain estates within Darjeeling and Kalimpong. The tea leaves are processed as black tea, though some estates have expanded their product offerings to include leaves suitable for making green, white, and oolong teas.
Tea seed oil is an edible plant oil. It is obtained from the seeds of Camellia oleifera.
Dongfang meiren(Chinese: 東方美人; lit. 'eastern beauty') or Oriental Beauty, or baihao(白毫), among other Chinese names, is a heavily oxidized, non-roasted, tip-type oolong tea originating in Hsinchu County, Taiwan. It is a tea produced from leaves bitten by the tea jassid, an insect that feeds on the tea plant. Terpenes are released in the bitten leaves, which creates a honey-like taste. Oriental beauty, white-tip oolong, and champagne oolong are other names under which dongfang meiren is marketed in the West.
India is the second largest producer of tea in the world after China, including the famous Assam tea and Darjeeling tea. Tea is the 'State Drink' of Assam. Following this the former Planning Commission Deputy Chairman, Montek Singh Ahluwalia had plans to officially recognise tea as the Indian "National Drink" in 2013. According to the ASSOCHAM report released in December 2011, India is the world's largest consumer of tea, consuming nearly 30% of global output. India is also the second-largest exporter of tea, after China.
Taiwanese tea includes four main types: oolong tea, black tea, green tea and white tea. The earliest record of tea trees found in Taiwan is from 1717 in Shui Sha Lian (水沙連), present-day Yuchi and Puli, Nantou County. Some of the teas retain the island country's former name, Formosa.
Andraca bipunctata is a moth of the family Endromidae. It is found in China (Yunnan), India, Bhutan, northern Thailand, Myanmar and Nepal. The larvae are referred to as bunch caterpillars.
Black tea is a type of tea that is more oxidized than oolong, yellow, white, and green teas. Black tea is generally stronger in flavour than other teas. All five types are made from leaves of the shrub Camellia sinensis, though Camellia taliensis is also rarely used.
Camellia taliensis is a small species of evergreen shrub whose leaves and leaf buds are used to produce tea.
Georg Jeoseph Kamel, whose name in Latin was Camellus was missionary to the Philippines, died in Manilla in 1706. […] Camellias were named in posthumous honor of George Joseph Kamel by Carolus Linnæus.
It is speculated that he never saw a camellia.
The first edition of Linnaeus's Species Plantarum published in 1753 suggested calling the tea plant Thea sinensis...
The generic names Thea L. (Sp. Pl.: 515. 24 Mai 1753), and Camellia L. (Sp. Pl.: 698. 16 August 1753; Gen. Pl., ed. 5: 311. 1754), are treated as having been published simultaneously on 1 May 1753. … the combined genus bears the name Camellia, since Sweet (Hort. Suburb. Lond.: 157. 1818), who was the first to unite the two genera, chose that name, and cited Thea as a synonym.
For a long time, botanists have asserted the dualism of tea origin from their observations that there exist distinct differences in the morphological characteristics between Assamese varieties and Chinese varieties... Hashimoto and Shimura reported that the differences in the morphological characteristics in tea plants are not necessarily the evidence of the dualism hypothesis from the researches using the statistical cluster analysis method. In recent investigations, it has also been made clear that both varieties have the same chromosome number (n=15) and can be easily hybridised with each other. In addition, various types of intermediate hybrids or spontaneous polyploids of tea plants have been found in a wide area extending over the regions mentioned above. These facts may prove that the place of origin of Camellia sinensis is in the area including the northern part of the Burma, Yunnan, and Sichuan districts of China.