What is Pu’er?
Pu-erh (or pu’er) tea tasting is a social practice that emphasizes shared sensory experience, wellbeing, and alertness. Pu-erh refers to processed leaves and buds from the broad-leaf variety of the tea plant (Camellia sinensis var. assamica (L.) O. Kuntze; Theaceae) native to the Upper Mekong River Region of China’s Yunnan Province (Ming and Zhang, 1996).
Historically, pressed green pu-erh was a main commodity on the caravan trade routes from Yunnan and Sichuan provinces to Tibet, Nepal, India, and Burma. These trade paths are now collectively known as the (Xi’nan Sichouzhilu) or Tea-Horse Road (Chama Dao; Yang, 2004). Sections of the Southern Silk Road are estimated to date over 1000 years (Yang, 2004). Tea oxidized and fermented during the trade journey as it interacted with moisture and temperature fluctuations, and its flavour transformed from bitter to mellow.Sinse anciant times we can’t beat nature at its own game, so we join it, and let microbes have their way with meat or cheese in the hopes of developing deeper, more complex flavours than the fresh versions can offer.
There’s less rot involved when we age drinks like wine, beer, and whiskey, but it’s still a testy alliance with nature—giving up the fresh, fiery tastes of youth for something deeper, layered, and more mature. Age, though it manifests in many forms, has a character all its own. You know it when you taste it; you’re drinking time.
The Western world’s long been keen on aging all kinds of drinks, but up until the last couple decades or so, the idea of applying the same principles to tea was largely unknown. Head over to China, though, and you quickly see that aged tea is as much a part of life as 21-year-old whiskey and prized vintages of Champagne.
Why age tea at all?
Most tea doesn’t so much age as turn stale and dead. But with the right environment, and the right tea, you get something utterly unique: a drink that slinks down your throat and hugs your belly, relaxes your muscles and calms your mind. The best aged tea is medicine you want to gulp, full of earth taste or stone fruit or wet, sweet soil. And for the complexity of what you’re drinking, it can cost way, way less per serving than that bottle of old Barolo. In tea activity of micro organisms changes the chemical structure of existing aromatic compounds and creates new ones that did not exist in the original leaves.
Numerous socio-linguistic groups in Yunnan Province, including the Bulang (Blang), Wa, Akha (Hani), Lahu, Yao, Hmong (Miao), Jinuo, De’ang, Dai, and Han, have produced pu-erh for centuries. They consume tea as a medicine, tonic, beverage, and food for energy and wellbeing. Some of the health related claims attributed to pu-erh include strengthening the immune system, balancing the body’s hot and cold levels, detoxifying blood, treating rheumatism and stones, remedying headaches, and reducing swelling and soft tissue. Additionally, pu-erh is valued for providing nutrition, aiding digestion, and preventing obesity.
In Yunnan in some villages still people prepare pu-erh as a food. For example, upland Bulang communities ferment pu-erh in underground pits for several weeks to years and eat the leaves as an accompaniment or salad. The Bulang also eat fresh tea with nanmi (a condiment made of several spices) and elder Bulang women chew tea leaves with a mixture of betel nut (Areca catechu L.; Arecaceae), lime, and other plants. Fresh and fermented tea leaves are partic- ularly eaten during celebrations such as the annual harvest and nature worship ceremony in tea agro-forests. The Jinuo roast tea leaves that are mixed with spices and wrapped in banana leaves.
Variability of pu-erh production
The Pu, an ancestral people of the Bulang, Wa and De’ang, are considered the first cultivators of the tea plant (Huang, 2005). Tea cultivation in southwestern China is estimated to date over 1700 years (Xiao and Li, 2002). Tea in Yunnan grows in forests, agro-forests, mixed crop fields, and terrace plantations. Forest tea includes tea trees that are wild, sparsely planted in forests, or trees that were cultivated and have become feral. Tea agro- forests (known as ‘ancient teagardens’ in Yunnan) are forest areas (0.5–3.0ha.) thinned for tea cultivation or swidden areas where plant regeneration is fostered. They are most often managed by smallholder upland communities in Yunnan, including the Bulang, Wa, Akha, Lahu, Yao, Hmong, Jinuo, and De’ang. The multi-storied vegetative structure of agro-forests provides soil fertility and pests and disease control (Jose, 2009). Mixed crop tea plots are created in tea agro-forests by replacing associated woody plants with rice or other crop production and by pruning tea trees to increase irradiance and promote crop growth. Agro-forests and mixed crop plots are examples of low intensive agro-ecosystems. In contrast, terrace tea (taidi cha/‘tableland tea’) plantations are agricultural-intensive monoculture systems. They are large fields most often managed for uniformity, high-yield, and efficiency where tea plants are cultivated in compact rows and are pruned to waist-high shrubs. This production mode usually relies on chemical fertilizer and pesticide input.
Pu-erh is most often processed as a compressed tea of various brick, cake, log, nest, and gourd shapes. Following harvest, tea leaves are processed as a type of loose green tea (san cha or ‘scattered tea’), which is the raw material for pressed green pu- erh (sheng bing or ‘raw cake’), aged pressed green pu-erh (lao bing or ‘old cake’), and pressed black pu-erh (shu bing or ‘cooked cake’). The processing of loose green pu-erh starts with withering and heat fixing leaves by pan-frying them on a wok to lower the moisture content and deactivate oxidative enzymes, e.g. polyphenol oxidase, catalase, peroxidase and ascorbic acid oxidase (Zhen, 2002). Pan- fried leaves are rolled by hand or by mechanical grinders in order to disrupt the cell walls to remove additional moisture and shape the plant material. Kneaded leaves are spread out, typically on bamboo mats, and sun dried to prevent spoiling and to capture the ‘taste of the sun’ (tai yang wei). These processing steps are similar to that of other green teas that function to prevent oxidation of phytochemi- cal constituents (Zhen, 2002), however the deactivation of enzymes is not as complete for pu-erh. Consequently, pu-erh has a distinct oxidizing process and develops a smooth taste with age. Pressed green pu-erh is prepared by steaming loose green pu- erh and compressing the supple leaves into desired shapes using bamboo or stone molds. The compressed tea is then sun dried.
Today, connoisseurs store pressed green pu-erh in clay jars, bamboo wrapping and baskets, caves, and underground pits in attempt to optimally age tea and transform its flavor. The charac- teristics of aged pu-erh, can artificially be imparted by a microbial food-processing technology (hou fa jiao, ‘post-fermentation,’ ‘cooking,’ or ‘ripening’) that was developed for pu-erh in the 1970s. The resultant black pu-erh involves oxidizing and heap-fermenting leaves for several hours to days following the rolling process of loose green pu-erh. Temperatures and moisture are often adjusted for controlled post-fermentation and leaves may intentionally be inoculated with selected microorganisms such as Aspergillus sp. (Trichocomaceae) (Ku et al., 2010). The oxidized and fermented leaves are then steamed, compressed, and dried. Black pu-erh is categorized as a post-fermented tea. The microorganisms in black pu-erh oxidize polyphenol compounds more completely than the enzymatic oxidation of other black teas (Xie et al., 2009), and create fermentation-derived compounds known as statins.
Sheng pu (raw pu-erh): is alive! Due to the natural presence of microbes post-fermentation slowly occurs over time through oxidation and microbial enzymatic reaction. This tea is not a stable product, but changes with aging. When young it tastes fresh and raw, somewhat green, with a bright yellow liquor and can vary immensely from sweet to bitter, floral to fruity, even smoky (often due to drying over fire on wet days). As it ages it looses the fresh raw bite and the tea liquor turns darker. A simplistic generality would be to say that it mellows, sweetens, thickens and gains improved character. Young sheng Pu-erh is cooling according to TCM (Traditional Chinese Medicine), while aged Lao Sheng cha becomes neutral.
Shu pu (ripe pu-erh): post-fermented by a process called Wo Dui (wet pileup) – a comparatively recent method in pu-erh processing since 1973 in an attempt to recreate natural post-fermentation in a controlled environment. The tea is piled over 1m high, sprayed with water and covered by wet cloth. The pile is turned over regularly and heat builds up due to microbial activity accelerating fermentation, typically for 30-45 days depending on the required level of fermentation. It generally needs a few years after production to remove bad smells resulting from fermentation – mouldy, earthy or damp aromas. It also can improve with age gaining sweetness and texture. Shu pu-erh does not taste the same as naturally aged sheng pu-erh but has its own unique merits! Infused it has a deep burgundycoloured liquor and should taste rich, deep and mellow with a thick mouthfeel, dark stonefruit flavours and sweet aftertaste. Shu Pu-erh is warming according to TCM.
Factors that effect taste
There are numerous factors associated with production environment to impact the taste of pu-erh, including harvest time, season, location, plant height and age, cultivar or landrace, altitude, fog, slope, temperature, canopy cover, soil, rain fall, and humidity.
There are 3 main factors which affect the health of micro-organisms in tea leaves and thus the aging process and the taste of your tea:
- Air Circulation
- Stable Temperature
- Appropriate Humidity
Good air circulation ensures the proper health and reproduction of micro-organisms in the tea leaves which in turn, ensures the on-going processes that create the distinctive aromatic compounds one wants in an aged Pu-erh tea. If air circulation is reduced too severely, these processes are diminished and the tea’s taste will be flat and the aroma very mild.
If you wish to facilitate aging in your Pu-Erh tea, it is important that the tea be exposed to some fresh air, or the air be freshened periodically. So use caution with sealed containers or small, narrow spaces such as small or sealed cabinets or under a bed, where access to fresh air could be poor.
Micro-organisms prefer a stable temperature environment to encourage reproduction. According to past experience, a temperature range between 20° to 30° Celsius (68° – 86° Fahrenheit) is ideal to maintain long term transformation of the leaves. Of equal importance is that temperature fluctuations occur slowly if one lives in a climate where the temperature shifts dramatically or often.
It is important not to store Pu-erh tea near a heater, open window or in a refrigerator where the temperature may be too hot or too cold or may shift too rapidly.
Tea leaves are very good at absorbing moisture from the air. An appropriate level of humidity can assist the reproduction of micro-organisms and excessively low humidity hinders reproduction. Additionally, excessive high humidity and lack of air circulation can lead to the development of mould which can ruin a tea.
Tea leaves are also very good at absorbing odours so it is important not to store Pu-erh tea in kitchens, washrooms or anywhere near heavy water usage.
An additional factor is light. Bright light slows micro-organic growth, so low light conditions are the most suitable for storing Pu-erh tea.
Pu-erh tea is the most complex, varying and least well definined type of tea, with varying production method, character and resulting taste profile. This also makes it one of the most fascinating! Here you can find a brief summary of this complex tea, designed to give you an overview of the variety and types of pu-erh tea – much like our carefully curated small collection!
The one defining character of all pu-erh tea is its origin; Yunnan in S.W. China. It is then best described by the triangle of pu-erh drinking. Yunnan – the local people who grow and cultivate this tea mostly drink and prefer freshly produced pu-erh – young Sheng cha (raw tea); Taiwan – most prized is Lao Sheng cha (old raw tea), which has post-fermented naturally over many years (if not decades) surmised by ‘yue chen, yue xiang‘ – the older the better; Hong-Kong – the most widely drunk and available pu-erh is Shu cha (ripe tea), because this is the best tea to aid digestion of their oil rich cuisine.
The gong fu cha dao (‘way of tea’ with ‘effort,’ ‘work,’ or ‘skill’) method of brewing tea is currently being revitalized and adapted in Yunnan in response to the recent expansion of the pu-erh mar- ket. Gongfu cha dao developed in eastern China and draws from earlier tea preparation methods documented in Lu Yu’s Cha Jing (‘Classic of Tea,’ written around 760–780 CE), considered the first monograph of tea (Lu, 1974). The gongfu cha dao method is based on multiple infusions of briefly steeping leaves in a lidded bowl or in an unglazed clay teapot (Fig. 1). The number of infusions, brewing duration, leaf amount, and water temperature used in preparing pu-erh varies with production and processing variables of tea and drinker preferences. Some pu-erh drinkers interviewed for this study during preliminary research claim that brewing tea through brief and multiple infusions functions to optimally release it’s aroma, taste, color, and physiological properties, thus providing for a ‘balanced composition’ that brings out nuanced essences.
A notable component of pu-erh tea tasting is for drinkers to compare and communicate their sensory perceptions of each infusion and to discern characteristics of how and where the tea was grown and processed. This practice is considered to keep the mind and senses vigilant through focus and communication. The first infusion prepared during the pu-erh tea preparation, and occasionally the second, is poured out in order to open the dried leaves and release their sensory properties for the following infusions. In some Tibetan communities of Yunnan surveyed by this study’s authors, pu-erh tea infusions are distributed in a hierarchical order. The most elder or senior drinkers are offered the first serving and the youngest or least senior drinkers receive the last infusions.
What health benefits have Puer tea?
Pu-erh tea has received much research and press about its health benefits . It is widely believed to aid digestion by breaking down oily and fatty food, increase the metabolic rate, improve blood circulation, lower LDL cholesterol levels (due to naturally occuring statins) and reduce the unpleasant symptoms of a hangover by eliminating toxins. Pu-erh is also drunk and enjoyed for its cha-qi (tea energy) which can vary from subtle to strong and affect both body and mind!
Storing Pu-Erh Tea
Both green and black varieties of Pu-Erh tea can be stored for long periods of time. In fact the longer the storage, the better the tea gets. We recommend storage in unglazed clay containers, either for long term holding or for drinking, since they “breathe” and reduce temperature fluctuations. Also can be used sealed cardboard box or even a paper bag, but make sure these have no chemical odours from manufacturing.
The best location for storage is a cool, dry place, away from temperature fluctuations and odours, such as those from the kitchen, as tea absorbs odours and this will affect the flavor of the tea.
For tea that is to be stored long term, simply leave it in the original paper wrapping or packaging. For tea that is to be consumed, break the tea into small pieces using a strong dull knife. Since more of the surface of the tea is now exposed to air, oxidation will develop the complexity of tea more rapidly. This is called “waking up the tea”. If you do not intend to drink a tea before 5 years, it is best to leave it stored and unbroken.
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