Pu'er or pu-erh is a variety of fermented tea traditionally produced in Yunnan Province, China. Pu-erh tea is made from the leaves of the Yunnan tea plant Camellia sinensis var. assamica, which is a specific variety of tea plant that is native to Yunnan. It differs from Yunnan tea (dianhong) in that pu'er tea goes through a complex fermentation process. In the context of traditional Chinese tea production terminology, fermentation refers to microbial fermentation (called 'wet piling'), 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 , though the term is commonly translated to English as "dark tea" to distinguish it from the English-language "black tea" (), which it is not.
Most teas, although described as fermented, are actually oxidised by enzymes present in the tea plant. Pu'er is instead fermented microbially by molds, bacteria and yeasts present on the harvested leaves of the tea plant, and thus is truly fermented.
There are two main styles of pu'er production: a traditional, longer production process known as ("raw") pu'er; and a modern, accelerated production process known as ("ripe") pu'er. Pu'er traditionally begins with a raw product called "rough" () () and can be sold in this form or pressed into a number of shapes and sold as . Both of these forms then undergo the complex process of gradual fermentation and maturation with time. The wòduī () fermentation process developed in 1973 by the Kunming Tea Factory created a new type of pu'er tea. This process involves an accelerated fermentation into that is then stored loose or pressed into various shapes. The fermentation process was adopted at the Menghai Tea Factory shortly after and technically developed there. The legitimacy of is disputed by some traditionalists when compared to the traditionally longer-aged teas, such as .
Pu'er can be stored and permitted to age and to mature, like wine, in non-airtight containers before consumption. This is why it has long been standard practice to label all types of pu'er with the year and region of production.
Name
is the pinyin romanization of the Mandarin pronunciation of Chinese is a variant of the Wade–Giles romanization (properly ) of the same name. In Hong Kong, the same Chinese characters are read in Cantonese as , and this is therefore a common alternative English term for this tea. The tea got its name from the ancient tea-trading town of Pu'er (), which is modern Ning'er Town () in Ning'er Hani and Yi Autonomous County, Pu'er City, Yunnan Province.. Pu'er County had its name changed to Simao, after Simao Town, the new county seat in 1950 following the proclamation of the People's Republic of China. The county of Simao became a prefecture-level city and had its name changed to Pu'er in 2007. Although the urban center of the modern Pu'er City remained in Simao, the whole Pu'er region is now sometimes considered the appellation for Pu'er proper.
History
Fermented tea leaves have had a long history among ethnic groups in southwest China. These crude teas were of various origins and were meant to be low cost. The Bulang and Dai people of Yunnan Province have produced pu'er tea at Jingmai Mountain since at least the 10th century. Traditionally, the tea trees would be planted in the forest understory after some larger trees were removed. On the border of these old tea forests, a partition forest would be planted to protect against the spread of pests and diseases, with cultivated land for crops and vegetables at lower altitudes. Darkened tea, or hēichá, is still the major beverage for the ethnic groups in the southwestern borders and, until the early 1990s, was the third major tea category produced by China mainly for this market segment. Because of the cultural significance of pu'er tea, its unique cultivation process, and the unbroken history of growing tea at Jingmai Mountain, it was inscribed as a UNESCO World Heritage Site in 2023.
There had been no standardized processing for the darkening of until the postwar years in the 1950s, when there was a sudden surge in demand in Hong Kong, perhaps because of the concentration of refugees from Mainland China. In the 1970s, the improved process was taken back to Yunnan for further development, which has resulted in the various production styles referred to as . This new process produced a finished product in a matter of months that many thought tasted similar to teas aged naturally for 10–15 years, so this period saw a demand-driven boom in the production of hēichá by the artificial ripening method.
In recent decades, demand has come full circle and it has become more common again for , including pu'er, to be sold as the raw product without the artificial accelerated fermentation process.
Processing
Pu'er tea processing, although straightforward, is complicated by the fact that the tea itself falls into two distinct categories: the "raw" shēngchá and the "ripe" shóuchá. All types of pu'er tea are created from , a mostly unoxidized green tea processed from Camellia sinensis var. assamica, which is the large leaf type of Chinese tea found in the mountains of southern and western Yunnan (in contrast to the small leaf type of tea used for typical green, oolong, black, and yellow teas found in the other parts of China).
Máochá can be sold directly to market as loose leaf tea, compressed to produce "raw" , naturally aged and matured for several years before being compressed to also produce "raw" or undergo wòduī ripening for several months prior to being compressed to produce "ripe" . While unaged and unprocessed, Máochá pǔ'ěr is similar to green tea. Two subtle differences worth noting are that pu'er is not produced from the small-leaf Chinese varietal but the broad-leaf varietal mostly found in the southern Chinese provinces and India. The second is that pu'er leaves are picked as one bud and 3–4 leaves whilst green tea is picked as one bud and 1–2 leaves. This means that older leaves contribute to the qualities of pu'er tea.
Ripened or aged raw pu'er has occasionally been mistakenly categorized as a subcategory of black tea due to the dark red color of its leaves and liquor. However, pu'er in both its ripened and aged forms has undergone secondary oxidization and fermentation caused both by organisms growing in the tea and free-radical oxidation, thus making it a unique type of tea. This divergence in production style not only makes the flavor and texture of pu'er tea different but also results in a rather different chemical makeup of the resulting brewed liquor.
The fermented dark tea is one of the six classes of tea in China, and is classified as a dark tea (defined as fermented), something which is resented by some who argue for a separate category for pu'er tea.Cf. For a rebuttal, see As of 2008, only the large-leaf variety from Yunnan can be called a pu'er.
Pu'er is typically made through two steps. First, all leaves must be roughly processed into maocha to stop oxidation. From there it may be further processed by fermentation, or directly packaged. Summarising the steps: Maocha: Killing Green () -- Rolling () -- Sun Drying () green/raw (, sheng cha) dark/ripe (, shu cha): -- Piling()-- Drying() Both sheng and ripe pu'er can be shaped into cakes or bricks and aged with time.
Maocha or rough tea The intent of the stage ( or ; literally, "light green rough tea" or "rough tea" respectively) is to dry the leaves and keep them from spoiling. It involves minimal processing and there is no fermentation involved.
The first step in making raw or ripened pu'er is picking appropriate tender leaves. Plucked leaves are handled gingerly to prevent bruising and unwanted oxidation. It is optional to wilt/wither the leaves after picking and it depends on the tea processor, as drying occurs at various stages of processing. If so, the leaves would be spread out in the sun, weather permitting, or a ventilated space to wilt and remove some of the water content. On overcast or rainy days, the leaves will be wilted by light heating, a slight difference in processing that will affect the quality of the resulting maocha and pu'er.
The leaves are then dry-roasted using a large wok in a process called "killing the green" (), which arrests most enzyme activity in the leaf and prevents full oxidation. After pan-roasting, the leaves are rolled, rubbed, and shaped into strands through several steps to lightly bruise the tea and then left to dry in the sun. Unlike green tea produced in China which is dried with hot air after the pan-frying stage to completely kill enzyme activity, leaves used in the production of pu'er are not air-dried after pan-roasting, which leaves a small amount of enzymes which contribute a minor amount of oxidation to the leaves during sun-drying. The bruising of the tea is also important in helping this minimal oxidation to occur, and both of these steps are significant in contributing to the unique characteristics of pu'er tea.
Once dry, can be sent directly to the factory to be pressed into raw pu'er, or to undergo further processing to make fermented or ripened pu'er. Sometimes is sold directly as loose-leaf "raw" Sheng Cha or it can be matured in loose-leaf form, requiring only two to three years due to the faster rate of natural fermentation in an uncompressed state. This tea is then pressed into numerous shapes and sold as a more matured "raw" Sheng Cha.
Pressing
To produce pu'er, many additional steps are needed prior to the actual pressing of the tea. First, a specific quantity of dry or ripened tea leaves pertaining to the final weight of the is weighed out. The dry tea is then lightly steamed in perforated cans to soften and make it more tacky. This will allow it to hold together and not crumble during compression. A ticket, called a or additional adornments, such as colored ribbons, are placed on or in the midst of the leaves and inverted into a cloth bag or wrapped in cloth. The pouch of tea is gathered inside the cloth bag and wrung into a ball, with the extra cloth tied or coiled around itself. This coil or knot is what produces the dimpled indentation at the reverse side of a tea cake when pressed. Depending on the shape of the pu'er being produced, a cotton bag may or may not be used. For instance, brick or square teas often are not compressed using bags.
Pressing can be done by: A press. In the past, hand lever presses were used, but were largely superseded by hydraulic presses. The press forces the tea into a metal form that is occasionally decorated with a motif in sunken-relief. Due to its efficiency, this method is used to make almost all forms of pressed pu'er. Tea can be pressed either with or without it being bagged, with the latter done by using a metal mould. Tightly compressed , formed directly into a mold without bags using this method are known as due to its density and hardness. The taste of densely compressed raw pu'er is believed to benefit from careful aging for up to several decades. A large heavy stone, carved into the shape of a short cylinder with a handle, simply weighs down a bag of tea on a wooden board. The tension from the bag and the weight of the stone together give the tea its rounded and sometimes non-uniform edge. This method of pressing is often referred to as: "hand" or "stone-pressing", and is how many artisanal are still manufactured.
Pressed pu'er is removed from the cloth bag and placed on latticed shelves, where they are allowed to air dry, which may take several weeks or months, depending on the wetness of the pressed cakes. The pu'er cakes are then individually wrapped by hand, and packed.
Fermentation