There are over 3,000 teas made from different varieties of Camellia sinensis. Like wine, a tea’s character, colour and flavour is dependent on a range of factors:
- Location of plantation
- Seasonal changes
- Cultivation methods
- Plucking methods
- Leaf processing
- Storage and transportation of final leaf
- Brewing of tea
White tea is named after the tiny white/silvery hairs that cover the bud on the tip of each shoot. It’s produced on a very limited scale and although originally from China it’s now produced in Sri Lanka.
After steaming the buds are dried and then shaped. White teas are champagne coloured and have a light, sweet and velvety flavour. The caffeine content, which is negligible, is the lowest of all tea types.
These teas are China’s rarest and are similar to white teas. New buds are left in piles to oxidise. The heat caused during this process dries them out thus preventing further decomposition. When brewed they give a pale yellow and greenish liquor with a delicate sweetness. Yellow tea has more caffeine than most green teas.
Green tea is often referred to as ‘unoxidised’ or ‘non-fermented’. Processing differs by region but is based on similar principles. Freshly picked leaves are withered (left out to dry) and then heat treated. In China the traditional method is still employed. Leaves are spread out and exposed to sunlight or warm air for a couple of hours before being placed into hot roasting pans. This makes the leaves soft and moist and allows the moisture to evaporate. After a few minutes the leaves are placed onto bamboo tables and are rolled.
Once rolled the balls are placed into the hot roasting pans for a second time before being rolled again. After one or two hours the leaves turn a dull green colour and undergo no further changes. At this stage the leaves are sieved to separate them out by size.
Oolong teas are generally known as ‘semi-fermented’ or ‘semi-oxidised’ and are traditionally the product of China and Taiwan. In order to give Oolong teas their rich flavour the leaves (one bud and three leaves) are picked near to their peak and processed immediately after plucking. The leaves are first wilted in warm air or direct sunlight, and are then shaken in bamboo baskets to lightly bruise the edges of the leaves.
This fermentation or oxidation period normally takes 1½ hours and is halted by firing once the surface of the leaves is yellow and the edges are a reddish colour. Oolongs are whole leaf teas and are never broken by rolling.
The production of black teas varies considerably by region but the process always involves four basic stages: withering, rolling, oxidation (fermentation) and drying (firing). The two major processing methods are ‘orthodox’ and ‘CTC’ (Cut, Tear and Curl method).
In the traditional method the leaves are spread out in warm air and allowed to wither until they’re soft enough to roll without the surface of the leaf splitting. Next the leaves are rolled in order to release the chemicals required for oxidation. Although this is sometimes done by hand, Rotorvane machines that lightly crush the leaf are normally used. The rolled lumps of leaf are then left in cool, humid atmospheric conditions for up to 4 hours to absorb oxygen. The chemical change in the leaf turns them from green to a coppery red colour.
The final stage requires the leaf to be oxidised or fermented to prevent natural decomposition. At this stage the leaves turn black and are recognisable as tea.
The Cut Tear Curl method is widely used in the production of black tea and produces smaller particles that give a stronger, quicker brew ideal for use in tea bags. The leaf is withered in the same way but instead of being rolled it’s passed through the rollers of a CTC machine which rotate at different speeds, or in a Lawrie Tea Processor (LTP) rotating hammer-mill leaf disintegrator, which tears and breaks the leaf into tiny particles. The remaining oxidation and drying stages are the same as the orthodox method.