Production



Growth of tea

Today tea is cultivated in many countries, like China, India, Sri lanka, Japan, Russia and Kenya. The ideal conditions for growing tea are slightly chilly temperatures and a mountainous terrain with a rainfall measuring at least 100 centimetres a year. Ideally, it likes deep, light, acidic and well-drained soil.   Tea varies in flavour and characteristics according to the type of soil, altitude and climate conditions of the area in which it is grown. The way it is processed also affects the flavour and characteristic, as does the blending of different teas from different areas

Tea is divided into two basic categories: green and black. Black tea leaves are fermented before they are dried, while green tea is not subjected to fermentation. Other varieties include semi-fermented Chinese Oolong and Formosan Teas and Chinese White Tea which is dried specially in the open air.

In various tea producing countries, where tea is grown on smallholdings, co-operatives are formed to build a tea-processing factory central to a group of smallholders. The owners of the smallholdings sell their plucked leaf to the factory for processing.
 

Cloning

Nowadays, tea is grown as a bush approximately one metre high, for ease of plucking, grown from cuttings or clones.  These are carefully nurtured in nursery beds until ready for planting out. Young bushes are planted approximately 1.5 metres apart in rows with a distance of one metre between each row.

In the higher altitudes these rows follow the contours of the hills or mountainsides to avoid soil erosion. At some of the higher altitudes terraces are built, again to avoid soil erosion.  The bush itself is trained into a fan shape, with a flat top, called a plucking plateau, about 1x1.5 metres in area and takes between three to five years to come to maturity. This is dependent on the altitude at which the tea is grown. Before the first plucking, the bushes are severely pruned by a method known as "lung" pruning.

The bushes are plucked, mostly by hand, every 7-14 days. Altitude and climatic conditions of the growing area are the two deciding factors in this regrowth period. A tea bush grown at sea level will replace itself more quickly once plucked, than a tea bush growing at a higher altitude, where the air is often cooler. Only the top two leaves and a bud are plucked from the sprigs on the plucking plateau.

How Tea is made

The preferred parts of the tea plant for processing into tea is the tip of the branch and the sprout-the well-known pekoe-and its two leaves. The plucked leaves are collected in a basket or bag carried on the back of the plucker and when this is full it is taken to a collection point where the plucked leaf is weighed before being taken to the factory for processing, or "making", as tea manufacture is known in the tea trade. On an estate, each plucker is credited with their own weights of tea for subsequent payment.

As black tea has the major share of the tea market in terms of production, sales and amounts drunk, most tea factories produce black tea.

At the Factory

On arrival at the factory, the plucked leaf is spread on vast trays or racks, normally placed at the top of the factory, and are left to wither (as shown below) in air at 25-30 degrees centigrade. The moisture in the leaf evaporates in the warm air leaving the leaves flaccid. This process can take between 10 to 16 hours, depending on the wetness of the leaf. Some factories will gently hasten the process with the aid of warm air fans.

The withered leaf is broken by machine so that the natural juices, or enzymes, are released and on contact with the air will oxidise. This breaking is done by two methods "Orthodox" and "Unorthodox" - terms are used to describe the machinery used. The Orthodox machine rolls the leaf, which produces large leaf particles, known as grades. While the "Unorthodox" term covers teas broken by either a CTC (cut, tear and curl) or Rotovane machine. Both chop the leaf into smaller particles than those which are produced by the Orthodox method. The smaller particles are more suited to modern market demands for a quicker brewing finished product.

The broken leaf is laid out either on trays or in troughs in a cool, humid atmosphere for 3-4 hours to ferment, or oxidise, and is gently turned every so often throughout the period until all the leaves turn a golden russet colour and fermentation is complete.
After fermentation, the leaf is dried or fired. This is done by passing the broken fermented leaf slowly through hot air chambers where all the moisture is evaporated and the leaf turns a dark brown or black. The black tea is ejected from the hot chamber into chests. Next it is sorted into grades, or leaf particle sizes, by being passed through a series of wire mesh sifts of varying sizes into containers before being weighed and packed into chests or "tea sacks" for loading onto pallets.
Factory tea-tasters will taste the finished make to ensure that no mistakes have been made during the manufacture or that the tea has not been contaminated by anything within the factory. Samples of the make are sent to selling brokers worldwide. All brokers will evaluate the tea for quality and price, reporting back to the estate or co-operative, so the tea can be sold to the best advantage.

After each "make" the tea factory is washed from top to bottom to ensure that the completed make does not contaminate the next make of tea.

Green Tea Manufacture

For green tea manufacture, the withered leaf is steamed and rolled before drying or firing. This is done to prevent the veins in the leaf breaking and thus stopping any oxidisation or fermenting of the leaf. When brewed, green tea has a very pale colour and the wet leaf is often left whole. Green tea is drunk mainly in China, Japan and some parts of South America. In the Western world green tea is sometimes drunk as a speciality tea.


source: The Tea Council