MANUFACTURE OF DARJEELING TEA
Darjeeling Tea is manufactured using conventional orthodox industrial technique which was developed in the 1800’s and is called in its amalgamation as “Orthodox Production”. The inherent Darjeeling Tea aroma is maintained by this method and the teas are produced without the procedure of “Cut, Tear and Crush” (CTC) of tender tea leaves. The stages are uniform even though a different variety of different leaves require a very delicate and intricate variation in processing. Since quality is the pivotal focus, it is never compromised upon by the tea planters in Darjeeling to produce quantity rather than quality. Recently the trend has started where few gardens manufacture green tea during rainy season, hitherto producing the finest quality of green and flavoury tea.
In the process, the initial stage is plucking of tea leaves mostly done by Nepalese women folk in special bamboo baskets carried with the help of a bamboo rope lashed on the head. The locals call the bamboo basket as "Doko" (Nepalese word) and is regarded as the cheapest and the most reliable medium to collect tea leaves. Once the plucked tea leaves reaches the factory, the plucked teas are sent for weighment and the labourers paid accordingly. The leaves then enter the actual process of "Orthodox Production" starting with the process of 'withering'.
WITHERING process of Darjeeling Tea
The first stage in Darjeeling Tea manufacturing is the process of withering. During this procedure the harvested tea flush is uniformly spread out on a withering trough which is normally 4 to 5 feet wide and 50 to 70 feet long. In Darjeeling processing approximately 65% of the moisture is removed from the green leaf by blowing hot and cold air for about 14-16 hours. The leaf becomes limp so as to withstand twisting and rolling under pressure without crumbling.
ROLLING process of Darjeeling Tea
The Darjeeling Tea leaves which are withered are put in the rollers which may vary in size. Normally, they are 36" and 48" sized rollers which are capable of rolling 70 to 120 kgs withered leaves. The pressure exerted on the tea leaf is in 'open and pressure' sequence. This procedure lasts for 45 minutes. During this process the green colour of the tea leaf is replaced by brown coppery coloured texture. This is because the process of rolling under pressure twist the leaf, rupture the cells and release the natural juices, promoting oxidation and acceleration of pigmentation.
FERMENTATION (Oxidative Process) of Darjeeling Tea
The rolled tea leaf after the rolling process is kept on the fermentation racks which are made out of tiles, cement or aluminum. Fermentation room is usually kept clean and cold and the process is carried out at a low temperature. During hot season a humidifier is used with less than 20°C hygrometric difference to keep the air humid. An experienced Darjeeling Tea maker judges the optimum fermentation on the basis of subjective assessment. The period of fermentation is affected by the type of tea leaf, degree of wither, temperature, availability of oxygen and fermenting ability of the tea flush. Therefore, the temperature period varies from 2 to 4 hours. Fermentation process is a very sensitive one. The flavour of any Darjeeling Tea can be affected by a minutes delay in adjusting the correct fermenting period. The colour becomes dark and coppery during this stage and a typical aroma develops. This stage, in which the flavanols combine with oxygen in the air, develops the unique flavour of Darjeeling Tea. This process is the one which differentiates a black, oolong and green tea variety. Black tea undergoes full fermentation; oolongs are semi-fermented while green teas are not fermentated at all.
FIRING or DRYING process of Darjeeling Tea
The tea leaf after the completion of the fermenting process is loaded on to the dryer, which is made of perforated moving trays. The temperature inlet is maintained at 200 to 240°C. In order to achieve the correct drying of leaves, thickness of the spread, speed of the trays and the volume of air blown through are regulated thoroughly. Increased temperature in the primary stages often causes case-hardening of the Darjeeling Teas while low exhaust temperature produces stewed teas. The complete procedure takes about 20 to 30 minutes approximately. A good fire reduces moisture content in the final product to about 2-3%. In order to maintain a correct balance of the volatile compound in the flavoury compounds of top rated teas, it is very important to keep the temperature at a high degree. The extremely fine and high quality mellowness is attained after the completion of enzymatic process of drying during which enzymes remain deactivated, but the maturation process continues, thus giving the desirable character of the “Savoury Darjeeling Tea”.
SORTING & GRADING process of Darjeeling Tea
The mechanically oscillated sieves are used for sorting out the tea in making different Darjeeling Tea grades. There is a gradual decrease in the sieve size from top to bottom which faciliates bigger size teas to remain on the top and the brokens to the bottom, hence defining different types of Darjeeling Tea.
It is the manufacturing process that decides what type of tea is to be created or manufactured. And this also depends upon the varios tea seasons - namely Darjeeling First Flush, Darjeeling Second Flush and Darjeeling Autumnal Flush.