Dark Tea: An Overview
Dark tea has consistently high production and sales volumes, ranking just behind green and black teas. It is primarily sold to ethnic minority regions, hence the name ‘border tea.’ The raw materials for dark tea are generally coarser, rich in cellulose, minerals, vitamins, and sugars, which provide the benefits of greasy food digestion and meat flavor elimination. This year, dark tea is being promoted as a health tea, gradually gaining wider acceptance.
Dark tea is a type of post-fermented tea. Records of dark tea date back to the Ming Dynasty in the ‘Gansu Tongzhi’, and many experts believe it can be traced back to the tea-horse trade of the Tang and Song dynasties, also known as the ancient Tea Horse Road, earning it the nickname ‘tea on horseback.’
Crafting Process of Dark Tea:
Killing green – Rolling – Piling – Drying
Piling is the key step in the post-fermentation of dark tea, where the tea leaves are stacked to a certain height and subjected to high temperature and humidity, allowing rapid fermentation under the action of microorganisms. According to the definition of fermentation, only dark tea and some yellow teas are truly fermented teas. Although black tea is called fully fermented, its fermentation process does not involve microorganisms; it is an enzymatic oxidation reaction between polyphenols in the tea leaves and oxygen in the air, which is not strictly considered fermentation.
Comparison of Fermentation Processes in Different Types of Tea:
Oolong tea: Withering – Greening (fermentation) – Killing green – Rolling – Drying
Black tea: Withering – Rolling – Fermentation – Over red pot (killing green) – Drying
Dark tea: Killing green – Rolling – Piling (fermentation) – Drying
The piling process involves two types of ‘fermentation’ occurring simultaneously, with microbial fermentation being the primary factor. This gives dark tea its unique flavor and a mild nature.
Characteristics of Dark Tea:
Dark teas are generally characterized by their oily black or dark brown leaf color, hence the name. The quality features of dark tea are dark leaves, red infusion, and a rich, mellow taste.
For ease of transportation and storage, dark tea is mostly made into compressed forms such as cakes and bricks. Dark tea can be stored for a long time under sealed, dry, light-free, and odorless conditions, with its quality changing over time due to aging.
Classification of Dark Tea:
Based on production areas and processes, dark tea can be divided into Hunan dark tea, Hubei old green tea, Sichuan border tea, and Yunnan-Guangxi dark tea. Hunan dark tea is represented by Anhua dark tea from Yiyang, with the ‘three tips, three bricks, and one flower roll’ being the most famous. Hubei old green tea is represented by the ‘Chuan’ brand old green brick from Chibi Yanglou Cave. Sichuan border tea, mainly for border sales, is divided into southern and northern routes, with Kang bricks and Jin tips as representative products.
Yunnan-Guangxi dark tea, represented by Liubao tea from Liubao, Guangxi, and Yunnan dark tea, represented by Pu’er tea from Yunnan. New raw Pu’er tea does not belong to dark tea, but old raw Pu’er tea, after several years of storage and slow natural post-fermentation, can be considered dark tea. Ripe Pu’er, which has undergone the piling process, is a standard dark tea.
Brewing Dark Tea:
First, warm the pot with boiling water. For aged dark tea, it is recommended to use a purple sand pot, which can remove some storage odors and make the tea soup smoother. [Water temperature: 100°C, tea-water ratio: 1:20~1:30] Since most dark teas are in the form of compressed tea, the pre-wetting should be determined based on the size, and tightness of the tea blocks pried open each time, with half expansion in the pot being ideal.
[First infusion is for rinsing and not for drinking] If the pile or storage odor is too strong, the tea can be pre-wetted twice, and after the infusion, the lid can be opened to let the miscellaneous odors dissipate. The infusion time for the first infusion depends on the degree of pre-wetting. It is essential to learn to observe the tea leaves and the extraction of tea soup color after infusion. Under the premise of sufficient pre-wetting, the first infusion should be around 10 seconds, followed by 2-4 infusions around 5 seconds each.
From the fifth infusion, it is appropriate to start brewing with a longer infusion time. Dark tea can generally be infused more than seven times, and for those with a high stem content and coarser leaves, the infusion time can be appropriately increased.
