Fixation, rolling, stacking, and drying are the steps in the production of dark tea. Piling is a dark tea-specific procedure. It is also a critical step in the production of black tea quality.
Because black tea leaves are selected rough and have a low water content, they must be fried at high temperatures rapidly and uniformly.
Once fixation is complete, black tea should be heated rolled immediately to achieve a nice form. The rolling processes are the same as for black and green tea.
After rolling the leaves, stacked on a bamboo mat, 15 ~ 25 cm thick, cover with a damp cloth to keep moist and keep heat, for piling process. The piling process should be based on temperature changes, timely flip 1 or 2 times.
The principles of chemical change of piling, there is no conclusion. Currently, there is the enzymatic role of academia, the role of microorganisms and heat are three theories, but it is generally believed that play a major role is the role of water and heat.
There are the baking methods and dry methods, to fixed the quality of dark tea and prevent deterioration.