Pu-erh Tea - Production - Pressing

Pressing

To produce pu'er, many additional steps are needed prior to the actual pressing of the tea. First, a specific quantity of dry máochá or ripened tea leaves pertaining to the final weight of the bingcha is weighed out. The dry tea is then lightly steamed in perforated cans to soften and make it more tacky. This will allow it to hold together and not crumble during compression. A ticket, called a "nèi fēi" (内飞) or additional adornments, such as coloured ribbons, are placed on or in the midst of the leaves and inverted into a cloth bag or wrapped in cloth. The pouch of tea is gathered inside the cloth bag and wrung into a ball, with the extra cloth tied or coiled around itself. This coil or knot is what produces the dimpled indentation at the reverse side of a tea cake when pressed. Depending on the shape of the pu'er being produced, a cotton bag may or may not be used. For instance, brick or square teas often are not compressed using bags.

Depending on the desired product and speed, from quickest and tightest to slowest and loosest, pressing can either be done by:

• A hydraulic press, which forces the tea into a metal form that is occasionally decorated with a motif in sunken-relief. Due to its efficiency, this method is used to make almost all forms of pressed pu'er. Tea can be pressed either with or without it being bagged, with the latter done by using a metal mould. Tightly compressed bǐng, formed directly into a mold without bags using this method are known as tié bǐng (鐵餅, literally "iron cake/puck") due to its density and hardness. The taste of densely compressed raw pu'er is believed to benefit from careful aging for up to several decades.
• A lever press, which was operated by hand for tight pressings and has largely been replaced by the modern hydraulic press.
• A large heavy stone, carved into the shape of a short cylinder with a handle, simply weighs a bag of tea down onto a wooden board. The tension from the bag and the weight of the stone together give the tea its rounded and sometimes non-uniformed edge. Due to the manual labor involved, this method of pressing is often referred to as: "hand" or "stone-pressing", and is how many artisanal pu'er bǐng are still manufactured.

Pressed pu'er is removed from the cloth bag and placed on latticed shelves, where they are allowed to air dry, which may take several weeks or months, depending on the wetness of the pressed cakes. The pu'er cakes are then individually wrapped by hand, and packaged in larger units for trade or commerce.