Detailed Explanation of the Processing Technique Flow of Pu'er Tea

When it comes to the unique quality characteristics of Pu'er tea, they are fundamentally determined by two aspects. First, the tea leaves used to make Pu'er tea must be Yunnan large-leaf tea. This is because the content of tea polyphenols, catechins, caffeine, theanine and water extracts in Yunnan large-leaf tea trees is generally higher than in medium- and small-leaf tea trees. Second, the special production technique of Pu'er tea.

The production technique of Pu'er tea is divided into traditional technique and modern technique. Regarding the traditional technique of Pu'er tea, the famous Pu'er tea expert and professor Zou Hongjie of Yunnan Agricultural University records in the book "Yunnan Pu'er Tea" as follows: In the early Qing Dynasty, the production of Pu'er tea was mainly completed by tea farmers. First, the tea farmers processed the best spring tea into bud tea, stamen tea and palace ball tea to tribute to the emperor. The green tea picked afterwards was fixed and then sun-dried, first made into sun-dried green maocha; then it was steamed and pressed into shape, made into round compressed tea. There are two technique details that are related to the final formation of Pu'er tea and must be mentioned here. The sun-dried green maocha technique determines that it is the green tea with the highest water content. At the same time, when it was transported out of the production area it had to be packed into bamboo baskets. To prevent the tea leaves from breaking into pieces, about 8 hours before packaging a small amount of clean water had to be sprayed on them, stirred evenly, and the tea softened by dampening, which further increased its water content. This sun-dried green maocha was transported out from the production area, about 12 days by human carrying and about 12 days by horse carrying, to the tea distribution center at that time (the main tea shop). At this point, this batch of tea had basically completed a preliminary cold fermentation process, changing from raw tea (unfermented) to lightly fermented ripe tea. At the main shop in Pu'er or Simao, part of the loose tea was sorted and sold domestically; part was steamed and pressed into cakes, every 7 round pieces as one tube, wrapped outside with bamboo shoot leaves. At this time, to make the bamboo shoot leaves soft they also had to be soaked in water, and then the tea was sold to the Tibetan areas. From Simao along the traditional Ancient Tea Horse Road -> Jinggu -> Jingdong -> Nanjian -> Xiangyun -> Lijiang -> the Yunnan-Tibet route to Lhasa. This road required more than 100 days in total. Although the journey was long, the air dry and the temperature low, the moisture contained in the tea leaves themselves and in the bamboo shoot leaves still caused these cake teas to slowly cold-ferment, forming the Yunnan-specific large-leaf post-fermented Pu'er tea. Its unique aged aroma and rich, mellow liquor color were especially loved by Tibetan compatriots. The formation of Pu'er tea was initially not intentional, but a historical product formed by specific geographical and climatic reasons and a specific transportation process.

The processing of modern Pu'er tea began in the 1970s. After the founding of New China, in the early 1970s, with the continuous expansion of China's foreign trade, the production of Pu'er tea fell short of demand. According to consumers' requirements for Pu'er tea, the Yunnan Provincial Tea Company developed artificially post-fermented Pu'er tea at the Kunming Tea Factory, and promoted new techniques and new technologies for modern Pu'er tea production at state-owned production plants such as the Menghai Tea Factory, bringing Pu'er tea processing into a new period that emphasized science and technology and valued quality and efficiency. Through comprehensive research on the entire tea processing technique process, namely raw materials, processing technique, chemical composition and quality inspection and evaluation, the scientific concept of modern Pu'er tea was established. Artificially post-fermented Pu'er tea is, on the basis of modern science and technology, the use of modern scientific and technological means such as pile fermentation to complete in a relatively short time the post-fermentation process that traditional Pu'er tea needed a long time to complete. Throughout the entire fermentation cycle, multiple pile fermentations and sun-dryings must be completed strictly according to the technique requirements, and fermentation must be completed under specified temperature, humidity and ventilation conditions. The process of artificial pile fermentation of Pu'er tea requires about 40 days. After completing the artificial pile fermentation, Pu'er tea still needs to go through air-drying and mellowing -> screening, picking and blending -> sterilization and other processes, and then be made into compressed tea or loose tea, etc., and after storage and mellowing (after-ripening) it can become Pu'er tea that is ready to drink.