Wo dui (渥堆, wòduī)

Wo dui (渥堆), or wet piling, is the microbial processing of moistened tea in heaps. It is central to shu pu-erh production; related processes are also used for other dark teas.

For shu, sun-dried mao cha is moistened and piled. The heap heats up as processing proceeds. Producers monitor temperature, moisture and fermentation, turn the tea, then dry it. Heap size and duration vary with the method: it need not be a huge pile or take a fixed number of days.

Wo dui changes the tea’s composition, colour and flavour, but does not exactly reproduce decades of sheng ageing. Sheng skips this stage; both types can subsequently change in storage. Lao cha tou are clumps that form during fermentation, not a separate tea cultivar.

Smell and taste help you decide whether you enjoy a batch, but cannot establish food safety. Mustiness, mould or a strong foreign smell should not be excused as “fermentation.” Do not try to recreate wo dui by dampening tea in home storage.

Related teas

Chinese tea glossary