Types of Manufacture

Details

Category: Uncategorised

Published on Tuesday, 24 April 2012 20:09

Written by Super User

Hits: 13001

All tea comes from the "Camellia sinensis" plant. However, location the climate, soil conditions, altitude, etc, and how the tea is processed, determines the flavor characteristics of the tea. Based on the method of production, teas can be divided into two categories.

Orthodox :

The traditional tea-making begins with “Withering” the freshly plucked leaf. Withering is inducing (with the help of warm air) the leaf to lose about half its moisture in the course of 12 to 18 hours. At the end of this phase of manufacture, the leaf is limp. This limpness helps the next stage of tea-processing known as “Rolling” whose object is to rupture the leaf cells for releasing the enzymes and to twist or curl the leaf. It is made possible by rolling the leaf in a machine for a couple of hours as if being squeezed between the palms of hands.

If the leaf was not limp, more than normal quantity of watery juice would be squeezed when rolling, resulting in loss of essential solids. Fresh or brittle leaf would not ensure a well-distributed rupturing of the cells while rolling. Moreover, limpness enables the leaf to assume the desirable twist or curl.

By rupturing the leaf cells, rolling sets off, though it does not complete, “Fermentation”. To complete the process, the mass of rolled leaf is preserved in a cool humid atmosphere. The total time taken between the commencement of rolling and achieving optimum fermentation is two to three hours, after which the enzymes must be destroyed. To arrest further fermentation the mass of leaf is exposed to hot air by passing it through a chamber where the air temperature is maintained between 200- 250 degree Fahrenheit. This process which is known as “Firing” goes on for half an hour by which time the colour of the leaf turns from bright gold to black. After the “Fired” leaf has cooled to ambient temperature, it is ready for ‘Grading/Sorting’

CTC :

The CTC process of manufacture is similar to that of Orthodox type except in the matter of rolling, which is much more severe. After a brief conditioning roll, the leaf is made to pass through a machine consisting two steel cylinders with fine tooth-like sharp ridges. The cylinders with only marginal clearance between them, move in opposite directions at speeds of 70 an 700 r.p.m. respectively. The objective is to ensure that most of the cells of the leaf is ruptured thereby achieving accelerated and intensive fermentation. The result is that the tea liquor is much thicker and yields many more cups of drinking tea per kg. The appearance of this type of dry leaf is granulated and of blackish brown colour.