Black Tea/Green Tea
the orthodox production method requires four kilos of picked tea leaves for one kilo of black tea.
Generally, the three youngest tea leaves are picked by hand. (700 leaves have to be picked for 100 g tea.) Depending on requirements and location, the leaves can also be harvested by machine. The leaves are then weighed and sent for further processing to the factory where the next processing steps take place:
The tea leaves are spread out on withering troughs (long grids or linen cloths on bamboo frames) and are usually ventilated for between eight and twelve hours with the help of fans. Up to 37 per cent of their water content and up to 30 per cent of their weight is removed from the leaves during the withering process.
After drying, the tea leaves are rolled through a machine (consisting of 2 plates rotating on top of each other with different pressures). This tears up the surface and breaks open the cell structure. This allows the cell sap to escape and react with the oxygen in the air (oxidation), thus allowing the tea to begin fermenting. Afterwards, the finest tea leaves are sieved out. This process is repeated up to four times.
The fermentation process started during rolling is accelerated by the supply of warm air. The room temperature is between 23 and 26 degrees Celsius, and the humidity is 95 per cent. This produces aromatic compounds and reduces the tannins in the tea leaf. The greenish-brown tea leaves turn reddish-brown.
Once the fermentation has reached the desired point, the tea leaves are heated in a kind of oven, which has a temperature of 85 to 125 degrees Celsius. This practically burns the cell sap onto the leaves, from which the black tea gets its typical black colour.
The tea leaves are then sorted by a sieve or leaf grade with the aid of mechanical vibrating sieves. For top teas, the final sorting is done by hand.
Leaf Tea – Broken Tea – Fannings – Dust
With this method, the leaves are crushed, torn and rolled (crushing tearing curling) after withering and being rolled between mandrel rollers. As a result, the cell structures are broken up more thoroughly and faster than in orthodox tea production. Only Broken Pekoe, Pekoe Fannings and Pekoe Dust are produced using this method.
Picking is done by machine or by hand, depending on requirements and location. CTC teas have a more intense cup colour and have a higher yield. After tearing, fermentation is initiated according to the desired leaf size and repeated several times. CTC teas are particularly suitable for tea bags.
Today, more than 50% of tea in India and almost 100% in Kenya is processed using the CTC method. In Darjeeling, however, only orthodox tea is produced.
This method is mainly used for tea bag production, and fannings and dust are produced almost exclusively. The process is named after its inventor and means Lawrie Tea Processor.
As in CTC production, the leaves are fed into a Rotorvane machine. The rapidly rotating knives cut the leaves until they are fannings and dust grade. The torn leaves are placed in large fermentation troughs and treated further in the same way as in CTC production.
Green Tea Production
The youngest white buds and the two leaves and a bud ) are picked by hand and processed by hand in the spring months of February to April.
Cheaper green teas are usually harvested by hand all year round and then processed by machine, whereas the very cheap teas are harvested with special picking machines.
Processing by Hand
The freshly picked tea leaves are briefly dried and steamed by hand in a heated pan. This prevents further oxidation or fermentation.
The leaves remain supple and do not break as easily during subsequent withering.
This is the only way to preserve the leaf’s full aroma.
The moisture is gently removed from the tea by heating the rolled leaves several times in pans and drying them externally, then cooling them down again and rolling them again. For the final drying, a small charcoal fire is lit, a raffia basket without a bottom is placed over it and a cloth in which the tea leaves lie is put on top. This method of processing is very expensive, which is why more and more machines are being used to perform these tasks and unfortunately also has an effect on the poorer quality of the tea. Chinese green teas have a typical smoky aroma.
Processing by Machine
Cheap green teas are steamed and dried in heated metal drums. The tea is then rolled between rotating metal discs or in heated pans with an automatic agitator and sorted by machine according to leaf size.
Tea is a natural product that is preserved by dehydration. Store it in a cool place
away from the sun and protect it from strong-smelling foods such as spices.
Opaque containers that can be sealed airtight are recommended for storing tea.