Insights Puer Shu

Often tea – in particular green tea, the main variety consumed by Chinese people – is appreciated for its freshness. Pu’er tea, on the contrary, has been valued only during the last years of the twentieth century and at the beginning of the twenty-first because the taste develops with aging. The indigenous people of Yunnan who grow this tea, prefer a pu’er – young Sheng cha (pure tea); Taiwan – the most renowned is Lao Sheng cha (old pure tea), which is naturally fermented over years (if not decades) just because “yue chen, yue xiang” – the older, the better; Hong-Kong – the most drunk and available pu’er is Shu cha (mature tea), it is the best tea to help digestion of their oil rich cuisine.

Why is tea allowed to age?

Historically, compressed green pu’er has been one of the main conveniences on trade routes from Yunnan and Sichuan to Tibet, Nepal, India, and Burma. These routes are globally known as Xi’nan Sichouzhilu or the Road and the Tea Horses(6). Some southern parts of the Silk Road date back over a thousand years (Yang, 2004). The tea oxidized and fermented during the journey as it reacted to moisture and temperature changes and its aroma changed from bitter to sweet.

Numerous socio-linguistic groups in Yunnan Province, including the Bulang (Blang), the Wa, the Akha (Hani), the Lahu, the Yao,the Hmong (Miao), the Jinuo,the De’ang, the Dai and the Han, have produced pu’er for centuries. They use tea as medicine, tonic, drink and food for energy and well-being. Some of the health benefits attributed to pu’er include strengthening the immune system, balancing body temperature, detoxifying the body, treating rheumatism and stones, treating headaches and reducing swelling in tissues. In addition, pu’er is believed to provide nutrition, aid digestion and prevent obesity.

Is the aging process like wine?

There’s less decomposition when we age beverages like wine, beer, and whiskey, but it’s still a matter of allying ourselves with nature – giving up the fresh flavor of the young product to achieve something deeper, more layered, more mature. Age, though it manifests itself in different ways, has its own particular strength. You can tell from the first taste. The western world has traditionally aged every kind of beverage, but until the last twenty years, the idea of applying the same practice to tea, was unknown. Looking at China however it is clear tea aged is part of everyday life just like a 21 years old whiskey or Champagne.

Many teas ageing become stale and die, but with the right environment, and the right tea, you will get something extraordinarily unique: a drink that slides down the throat and envelops us, relaxing the muscles and calming the mind. The best aged tea is a pleasant medicine, full of the taste of earth or fruit or moist and sweet soil. Plus, despite the complexity of the beverage, it will always cost less than drinking a bottle of aged Barolo. In tea, the activity of microorganisms changes the chemical structure of the existing aroma and creates a new one, non-existent in the original leaves. Since ancient times, not being able to beat natural balance, we chose to have it as an ally and let microbes act on meats and cheeses, in the hope of getting something deeper and more complex in flavor than what fresh products can offer.

Types of Puer Tea

To this day pu’er tea can be classified in three different types, according to the degree of post-fermentation. The first type is raw pu’er (Sheng cha), made by using large tea leaves, which can be too strong if you are young. Some tea experts claim post – fermentation is a key characteristic in the production of pu’er, however raw pu’er does not go through the post – fermentation phase and for this reason it resembles a lot to white tea.

Questo tè può anche essere pressato in una torta, a forma di ciotola, mattoncino o zucca, o può rimanere sfuso, pratica chiamata maocha. Questa maocha può invecchiare più velocemente, a casa dello spazio tra le foglie sfuse e presenta un sapore diverso rispetto alle foglie compresse.

The second type is raw aged pu’er (lao sheng cha), which should be at least five years old, even though there is still no agreement about the level of aging required to consider a tea aged.

Sheng pu’er is alive. A causa della naturale presenza di microbi, la post – fermentazione si verifica lentamente nel tempo grazie all’ossidazione e alla reazione enzimatica microbiale. Questo tè non è un prodotto stabile, cambia nel tempo. QUando è giovane è fresco e crudo, un poco verde, con un liquido giallo brillante e può variare dal dolce all’amaro, dal floreale al fruttato, anche affumicato (sapore dato all’asciugatura sul fuoco nei giorni umidi). Invecchiando però perde la sua freschezza e il liquido diventa più scuro. Parlando in generale potremmo dire che matura, si addolcisce, si addensa e migliore il suo carattere. Lo Sheng pu’er giovane è calmante, come indicato dalla TCM (Medicina Tradizionale Cinese),mentre lo Lao Sheng cha invecchiato diventa più soffice. Generalmente più il tè è vecchio, più alto è il prezzo. I prezzi altissimi del tè pu’er invecchiato a Hong Kong e Taiwan – come la torta di sette anni (357 gr) venduta a più di un milione di yuan – ha ispirato le produzioni a puntare di più sul tè pu’er.

The concept of “natural” is always very relative, because some create humid storage environments to accelerate the fermentation process, which allows us to move from the second to the third type.

It is an artificially fermented tea, also called “mature” pu’er (shu cha), product of a different processing, used to mature the hardness of raw pu’er tea. The post-fermentation phase takes place with a process called (wet stacking) – a new method used to process pu’er since 1973 (created in Kunmin) to recreate natural post-fermentation in a controlled environment. The tea is stacked over one meter high, sprayed with water and covered with damp cloths. The stack is turned regularly and the heat increases due to the activity of microbes, accelerating fermentation.

A few years of post-processing is required to remove the bad odors released by fermentation – a muddy, earthy, wet aroma.It can also improve with time, gaining sweetness and body. Shu pu’er doesn’t taste the same as naturally aged sheng, but it has its merits! When infused, it has a deep burgundy red color and has a rich, intense and ripe taste.Its aroma is thick, reminiscent of the drupe scent and has a sweet aftertaste. According to TCM (Traditional Chinese Medicine), Shu Pu’er is warming. In the market, artificially fermented tea is also said to be “naturally” fermented for a long time, resulting in an artificially fermented pu’er.

Ariety of Puer production

pu’er is often processed as compressed tea in various forms of bricks, cakes, logs, baskets. After harvest, the tea leaves are processed as green tea leaves (san cha or ‘scattered tea’), or the raw material of compressed green pu’er leaves (sheng bing or ‘raw cake’), pressed and aged green pu’er (lao bing or ‘old cake’), or pressed black pu’er (shu bing or ‘baked cake’).

Processing of green pu’er bulk leaves begins with wilting and heating the leaves in the wok pan to reduce moisture and deactivate oxidizing enzymes, such as polyphenol oxidase, catalase, peroxidase, and ascorbic acid oxidase (Zhen, 2002).  Pan-cooked leaves are shaken by hand or by mechanical arms to remove moisture and shape the product. The processed leaves are placed on bamboo mats, and dried only so as not to be spoiled and to capture the “flavor of the sun” (tai yang wei).  These steps are similar to those of other green teas which serve to prevent oxidation of the phytochemical components (Zhen, 2002), however deactivation of the oxidizing enzymes is not yet complete.

Pu’er in fact has a distinct procedure for oxidation and develops a more velvety taste over time. Pressed green pu’er tea is prepared by heating the loose leaves and passing them into the desired shape with bamboo or stone blades. The pressed tea dries in the sun.

Factors affecting taste

There are numerous factors associated with the production environment that can affect pu’er taste, harvest time, season, region, plant height and age, cultivar, altitude, fog, slope, temperature, cover, soil, rain fall, and humidity.

There are three main factors which impact on microorganisms in tea leaves and therefore on the aging process and the taste of tea.

In Yunnan, in some villages, people prepare pu’er as if it were food. For example, northern Bulang people ferment pu’er in underground wells for many weeks or years and eat the leaves as a side dish or salad. The Bulang also eat fresh tea with nanmi (a condiment made from various spices) and older Bulang women chew the leaves with a mixture of betel nut (Areca catechu L.; Arecaceae), lime and other plants.

Fresh and fermented, tea leaves are often eaten during celebrations, such as the annual harvest and nature veneration festival celebrated in tea forests. Jinuo people grill the leaves by mixing them with spices and wrapped in banana leaves.

• Air circulation
• Stable temperatures
• Right degree of humidity

Air circulation system

Good air circulation ensures the health and reproduction of microorganisms in tea leaves, which, in return, ensure the continuous process of the creation of new aromatic components, required in aged pu’er. If air circulation is drastically reduced, these processes slow down and the tea will have a dull taste and a very light aroma. In order to facilitate the aging of pu’er tea, it will be important for the tea to be exposed to fresh air or to have its circulation renewed periodically. Therefore pay attention to sealed or too small containers, narrow spaces such as sideboards or boxes under the bed, where the air supply becomes scarce.

Stable temperatures

Microorganisms can proliferate when temperatures are stable. Based on past experience, a temperature between 20 and 30° C is ideal for maintaining active long-term leaf transformation. Also of great importance is the slow transition from one temperature to another in climatic conditions where there are frequent temperature changes. Do not store pu’er tea near heat sources, open windows or freezers, where the temperature could be too high or too low.

Right degree of humidity

Tea leaves absorb moisture well from the air. The right level of humidity can help the reproduction of microorganisms, whereas low humidity hinders it. Excess humidity or lack of ventilation can instead lead to the development of mold, which will ruin the tea.

Tea leaves also absorb odors, therefore it is advisable not to store them in the kitchen, in the laundry room or in any other place where there is a great use of water.

Another incisive factor is light. Intense light slows down the growth of microorganisms, therefore low light is one of the best conditions for the preservation of pu’er. This tea is the most complex, varied and less defined of all; it has various production methods, character and results in terms of taste.  This is what makes it fascinating! Here is a summary of pu’er characteristics, designed to give you an overview of pu’er tea varieties and types – just like our little collection! The distinguishing feature of all pu’er is its origin: the Yunnan of Southwest China, also known as “the triangle where pu’er is drunk”.

Gong Fu preparation of pu’er and accessories

The gong fu cha dao (‘way of tea’ ‘with commitment’ ‘work,’ or ‘skill’) method for infusing tea is being valued and adopted in Yunnan in response to the recent expansion of the pu’er market. Gong fu cha dao developed in eastern China and originates from methods of tea preparation, of which we have evidence in Lu Yu’s Cha Jing (‘The Classic Tea’ written around 760-780), considered the first monograph on tea (Lu, 1974).

The Gong fu cha dao method is based on multiple, short infusions of the leaves in a lidded bowl or unglazed ceramic teapot (Fig. 1). The number of infusions, their duration, the amount of leaves, and the temperature of the water varies with different tea processing and drinker preferences. In a research interview, some pu’er drinkers stated that steeping the tea multiple times for a short time allows it to release its aroma, taste, color, and physiological properties, thus providing a “balanced composition” that brings out the different nuances of its essence.

A notable component of pu’er tasting for drinkers is to compare and communicate their sensory perceptions to each brew to distinguish the characteristics, how and where the tea was harvested and produced.

This technique is used to calm the mind and keep the senses awake with concentration and communication. The first infusion, and occasionally the second, are used to open the dry leaves and release the sensory properties for the infusions to follow.

What health benefits does pu’er tea have?

Pu’er tea has been the subject of research and journalistic investigation for the benefits it brings to health. It is known it helps digestion by breaking down oily and fatty foods, increases the rhythm of metabolism, improves blood circulation, lowers cholesterol levels (thanks to natural statins) and reduces annoying post lunch symptoms by eliminating toxins. Pu’er is also tasted for its cha-qi (tea energy) which can vary from fair to strong and impacts both the body and the mind! For more information, you can read the article on the health benefits of pu’er.

Store pu’er tea

Green and black variants of pu’er can be kept for long periods of time. In fact, the longer the storage, the better the tea will taste. We recommend non vitrified ceramic containers, both for storing and drinking them, as they breathe and reduce temperature changes. Cardboard boxes or paper bags can also be used, making sure they do not have chemical odors derived from manufacturing. The best place to store tea is cold and dry, away from temperature changes and kitchen odors, as tea absorbs and could be affected by them. For tea that is to be kept for a long time, leave it in its paper wrapping or packaging. The one that is to be consumed instead, break it in small pieces with a knife.

Since it is the surface of the tea that remains exposed to the air, oxidation will develop the complexity of the tea faster. This is called “the awakening tea.” If you don’t plan on drinking the tea for another five years, it’s best to store it intact.

References:

Zhen, Y.S., 2002. Tea: Bioactivity and Therapeutic Potential. Medicinal and Aromatic Plants – Industrial Profiles. Taylor and Francis, London.

Jing Hong Zhang, 2013. Puer tea. Ancient caravans and Urban chic. University of Washington press, Seattle and London.

Lin, Y., Tsai, Y., Tsay, J., Lin, J., 2003. Factors affecting the levels of tea polyphenols and caffeine in tea leaves. Journal of Agriculture and Food Chemistry 51, 1864– 1873.

Pu-erh tea tasting in Yunnan, China: Correlation of drinkers’ perceptions to phytochemistry. Selena Ahmeda, Uchenna Unachukwuc,f, John Richard Steppd,g, Charles M. Petersa,d, Chunlin Longd,e, Edward Kennelly.

Chen, S.T., Dou, J., Temple, R., Agarwal, R., Wu, K.-M., Walker, S., 2008. New therapies from old medicines. Nature Biotechnology 26, 1077–10

Chama Dao; Yang, 2004

Ming and Zhang, 1996