All tea comes from the Camellia sinensis, an evergreen shrub or tree from southern China and Southeast Asia. From the leaves of this plant, we can obtain, depending on the type of process to which it is subjected, different varieties: green tea, white, black, Pǔ'ěr 普洱, Wūlóng 烏龍… Let's see how tea is made.
The traditional or orthodox tea production consists of five elementary steps: harvesting, wilting, rolling, oxidation (commonly, and almost always erroneously, called "fermentation") and drying. Not all varieties are produced following these steps: some follow only a few, while others repeat some of them several times.
The traditional production of tea consists of five elementary steps: harvesting, wilting, rolling, oxidation and drying.
Next, we will describe each of these steps in more detail:
The collection of the leaves is traditionally done by hand. The tea plants are kept as shrubs at a suitable height to allow harvesting. The traditional rule of "two leaves and a bud" dictates that, in order to obtain a quality tea, only the terminal bud with the two tender leaves underneath must be collected.
It consists in spreading the leaves on a flat surface, to allow them to soften as they wilt, becoming more flexible. This allows the subsequent rolling in different forms without breaking the leaves. The withering takes between 12 and 18 hours approximately, in which the leaves have to turn several times to allow a homogenous exposure to the air.
It is at this time when each tea acquires its characteristic appearance, and when the process of flavour development begins. The leaves, already soft, are rolled or compressed in different forms, and are squeezed to extract their juices. The rolling allows a better preservation of the essential oils and aroma (the more compressed the leaves are rolled, the longer they keep their aroma).
After rolling, when the enzymes and essential oils of the leaf are exposed to the oxygen of air, the oxidation process begins, which produces changes in the chemical composition and the colour of the leaves, turning them brown and reddish. It is during oxidation that more complex flavours develop, which define each variety. The duration of this process depends on the climate and the variety produced, but it can happen in a matter of a few hours. The leaves can then be rolled and/or oxidized again, although oxidation occurs only once in most types of tea.
Formerly it was believed (erroneously) that the leaves fermented during this process, so the name "fermentation" has remained to this day to refer to oxidation. However, some types of tea do undergo an authentic fermentation.
It is the last step in the production process. The leaves can be roasted or heated quickly to remove the remaining moisture, stop oxidation, firmly adhere cellular fluids to the leaves and allow a good conservation of them.
There is also an alternative or heterodox production, more modern, in which the same steps can be followed but using mechanical or artificial means to accelerate the process.
In a next article we will see how each of the steps affects the achievement of a variety of tea or another.