Temperature – the most mysterious things for Pu-erh
Tea leaves from Yunnan large leaf species ( 晒青毛茶) are the best material for Pu- erh tea. The term Yunnan large leaf variety (a well-bred tea species grown in Yunnan) is an umbrella term especially refers to those large leaf species native to southwest Yunnan and Lantsang river basin mainly including Mengku variety, Fengqing variety and Menghai variety, etc.
Fresh leaves of Yunnan large leaf species
From fresh tea leaves to finished pu-erh, even to tea wate, temperature controlling can be seen all the ways.
Pu-erh tea growth and temperature
Like other tea plants, pu-erh tea trees grown in Yunnan, in southern China, requires appropriate temperature to breed and grow. Both soil and air temperatures have close relationships with pu-erh tea growth.
Yunnan large leaf tea trees
The optimal temperature for pu-erh tea growth varies from species to species, however, the optimum growth temperature for most of pu-erh trees would be 20～30℃. Within this temperature range, the higher the temperature is the faster they grow. But too high or too low would be disadvantageous for them.
Generally, large leaf tea species cannot grow normally under the temperature below 0℃, more worse they are easily injured or killed by frost when temperatures falls to -5℃ or more lower. So, it is no doubt to say pu-erh tea has a high requirement on temperature. One of the reasons why pu-erh tea trees are widely seen in Yunnan rather than other parts of China lies in the mountainous terrain here providing advantageous climatic conditions for pu-erh tea cultivation.
Pu-erh tea processing and temperature
Tea garden in winter
There is a saying that raw materials decide the quality. For pu-erh tea production, it can be explained as even if you have a pile of high quality fresh tea leaves, they may finally end up with nothing if processed with bad ways under dad external conditions (such as improper temperature). The temperature controlling becomes more important when going into processing steps (withering, de-enzyming, rolling). For example, freshly picked tea leaves piled into stacks waiting to be withered, if not handled properly, will be damaged by the inner constantly increasing heat and become useless.
Maintaining temperature to a reasonable level is priority among priorities in fermenting process of making ripe tea. Excessive high or low temperature is dad for tea fermentation, the former may burn the inner leaves and the latter may result in incompletely fermented tea leaves.
Newly plucked tea leaves on bamboo mat
In addition, it is equally important to control the temperature when storing or processing pu-erh crude teas which are going to be processed into compressed pu-erh tea. Excessive temperature can lead to too much broken bits due to the reason that high temperature can evaporate excessive water contained in crude teas and make them more easily to be broken off. To avoid this, some ripe teas need to be “washed” with water or steam to add its tenacity.
Water temperature for brewing
It is not difficult to understand that different teas need different water temperature to brew. Bear this in mind and try several times to master this skill if you don't want to get a cup of tea with bitter or insipid taste. When facing an unfamiliar pu-erh tea, apply all knowledge about this tea you could find to get the recommended brewing method including what amount of water should be used, the right brewing temperature as well as how long you should brew, these information can be easily found on the package or internet. If temperature of water is changed, it may lead to significant changes in tea taste and flavor. The very hot water tends to make tea liquid looks darker and tastes stronger than those brewed with lower temperature under the same brewing conditions because high temperature can steep out more substances (minerals) which can enhance tea aroma and enrich the mouthfeel. However, this does not mean that the higher the better. It depends on your personal taste and tea type. Some high grade pu-erh tea usually made of tender leaves are easily scalded by very hot water hence boiling water should be not allowed. Whereas it is good to use boiling water to brew other pu-erh tea or compressed tea made with slightly elder tea.
Forming though braising and pressing
Storage temperature for pu-erh
Many customers are usually misguided by some webpages or some untrustworthy material and storage their pu-erh tea in refrigerator hoping by this way they can keep them in good condition for a longer time. It is a big mistake. To keep your pu-erh tea in good condition for a long time, you’d better store them under room temperature (20~30℃) free from daylight. High storage temperature(above 30℃)may accelerate the normal fermentation speed and degrade quality. Please remember no matter where and when your pu-erh tea should be kept away from sunlight.
Traditional way of storing pu-erh tea using clay pot