Almost everyone is familiar with a few varieties of teas, such as e.g. black tea, green tea and white tea. A smaller ‘in-crowd’ has heard of the existence of e.g. oolong tea or pu erh-tea. But how would you call rooibos? Or what exactly is herbal tea?
All tea varieties are produced from one plant: Camellia Sinensis. From this plant two varieties are suitable for tea consumption and are being cultivated, namely Camellia Sinensis Sinensis (which originates in China) and Camellia Sinensis Assamica (a wild tea plant variety, that originates in the Centre and North-eastern part of India).
The production methods for black teas may vary slightly for every region, but the basic process always consists of four steps, which can be applied in different intensities: withering, rolling, oxidation and drying/baking. After the leaves are picked they are withered in the sun for some time. Part of the moisture in the leaves will evaporate and the leaves will become limp. After this step the leaves are rolled to make sure the flavours are released. Next, the leaves are spread out for hours to ferment (or oxidise). At the end of the production process the leaves are collected and roasted in large (wok)pans to stop the oxidation. During this last step the tea will get its recognizable black colour and strong fragrance.
When the black teas are produced the oxidation step will take much longer compared to produced green, white or oolong teas. This gives black teas its stronger flavour and higher level of caffeine (or theine) compared to the lighter oxidised varieties.
Green tea is also called ‘unfermented’ tea. After picking and withering the leaves, they are usually immediately baked to stop (or even: prevent) the oxidation process. The leaves will get soft and moisty when being baked in the hot pans. During this step the leaves are also rolled, to bring out the full flavours. After rolling the leaves they are immediately baked again. In the next few hours the leaves will get a dull-green colour and are ready for preparing tea. Rolling the leaves is sometimes still done by hand to give certain tea varieties their specific shape or form. Imagine the small densely rolled pearls of a Gunpowder tea, or the shape of crescents for Chun Mee. The steps as described above lay out the Chinese method of producing tea. In the Japanese method the leaves are not baked, but treated with hot steam for about 15 to 20 seconds. This also stops the oxidatioon process of the leaves, but shapes the leaves in a different form. (Small, elongated strips, e.g. ‘sencha’ or ‘bancha’-tea).
White tea was originally named after the small, white hairs that grow out of the buds of the tea plant. White tea originates in China, but it is these days produced in a number of different countries. For white tea it is not the leaves on the branch that are used, but the buds at the end of that branch. The buds consist of very young, not completely matured leaves. This makes white tea more rare because much less is available. The rarity of white tea automatically leads to increased values. After picking the buds they are usually steamed and dried at a low temperature. There are also plantations that simply dry the buds in the sun after picking them. The buds are not rolled so almost no oxidation takes place. Using this minimal way of processing the buds still contain almost all of their antioxidants.
In the spectrum of main varieties, oolong teas can be found somewhere between green and black teas. Therefore oolong teas are also called ‘half-fermented’ (or: half-oxidised) teas. Where green teas consist of hardly oxidised leaves and black teas are fully oxidized, the oxidation level of oolong tea is somewhere in between. There are roughly two main groups of oolong teas: the greener variety (closer to green teas) and a more oxidised variety (more oxidation, so more close to black tea). The production process of green oolong teas is done in almost the same way as the darker varieties. However the leaves are already baked after reaching an oxidation level of about 20 to 30%. After the baking process the leaves are rolled into small pebbles. When the tea leaves are allowed to oxidize further (e.g. 40-50-60%) the leaves will get a dark brown colour and produce different notes. When tea leaves reach an oxidation level of over 70%, we call it black tea, because the difference between both of them becomes difficult to determine. Oolong teas are often drunk in its purest form, but can also be flavoured with essential oils, herbs, flowers, etc. as it is also customary these days for black, green and white teas.
Besides varieties of teas there are also a number of tea-like beverages that are really popular. However, they are not produced from leaves of Camellia Sinensis. The most well-known (and mostly drank) variety is rooibos (originated from South Africa), but there is a number of alternative herbal and fruit infusions.