‘Good fermentation makes good quality tea’

The company has a factory that is fully equipped with processing machines and retail line that can pack bulk tea into chests and cartons of 25 kilogramme capacity and more.The factory which was designed to produce 1.6 million kilogrammes of black tea per annum has so far produced 1.2 million kilogrammes as its highest annual […]

The company has a factory that is fully equipped with processing machines and retail line that can pack bulk tea into chests and cartons of 25 kilogramme capacity and more.
The factory which was designed to produce 1.6 million kilogrammes of black tea per annum has so far produced 1.2 million kilogrammes as its highest annual production since production began in 1982.
Tea is manufactured in three main ways, namely: the CTC- (Cut/Tear and Curt) method, the orthodox method and the Lawrie Tea Processing (LTP) method.
Assistant General Manager, Production and Engineering of the company, Mr Jonathan S. Chiwar, said the company adopts the Lawrie Tea Processing (LTP) method in producing its tea.
According to him, there are about seven basic stages or steps involved in the manufacturing of tea in the factory, namely, plucking, leaf reception, withering, cutting, fermentation, drying, sorting/grading and packaging.
The process of tea manufacturing starts with plucking of the tea leaves right from the field. The young shoots which grow quickly are plucked every 7 to 14 days. Only the leaf bud plus two leaves otherwise known as ‘two leaves and a bud’ are plucked.
The reason for plucking it as two leaves and a bud, according to Mr Chiwar, is to enhance quality in tea production. The plucked tea leaves are carried in plucking baskets to collection point for checking and weighing. It is thereafter transported by special green leaf trailers to the factory. “We have what we call plucking standard; the plucking standard is two leaves and a bud,” he said.
He however noted that due to human errors, sometimes those engaged in the plucking do harvest up to three or four leaves and a bud which is capable of affecting the quality of tea production. The leaves are usually weighed to ascertain the difference between field and factory weights to ensure quality before they are moved to the next stage which is called ‘withering’.
Withering in tea processing is a process of reducing the moisture content of the green leaf. The plucked leaf is first spread on racks in a current of warm air. This removes the moisture from the leaf leaving it in lumps. The leaf is usually withered to about 75% to 78%. There are withering troughs used for tea withering. During hot weather, up to 80% wither is required.
Reversible fans are used to assist in ensuring evenwithers from top to bottom of the leaf which are alternated every two hours. It takes between 8 to 16 hours for the withering process to be completed depending on the weather condition and loading of leaf on the bed or withering troughs. The natural withering however takes between 18 to 20 hours to be completed.
“The essence of the withering is to reduce the moisture content so that you can get a good quality tea, freshly plucked tea contain about 80 to 82 moisture content”, Chiwar said.
He said each withering trough has the capacity of containing about 800 kilogrammes of green leaf and there are 48 of them at the factory.
The withered leaf is usually collected from the withering troughs and put in bags. The bags are hooked on a monorail conveyor and taken into cutting room though a sifter. The sifter is fitted with a magnet to remove any grit or piece of metal. The leaf then passes through a Lawrie Tea Processor (LTP) whose blades move at 1,000 rpm and cut the leaf into fine particles.
“Within the LTP, we have what we call ‘knives and beaters’ which cut the leaves into smaller particles; the knives are 36 while the beaters are 124 in number. The LTP moves at 2,500 revolutions per minute. As the LTP turns faster, it cuts the green leaves into smaller particles.
The leaf particles are placed on perforated fermenting trolleys. The crushed leaf is then allowed to ferment to a bright coppery colour. The leaves absorb oxygen which causes the colour to change. This process is called oxidisation. The fermentation period is about 90 minutes. The room temperature and relative humidity should also be controlled as these affect fermentation.
Good fermentation makes for good quality tea. The leaf quality also affects fermentation. The harder the leaf, the slower the fermentation and the softer the leaf, the faster or quicker the fermentation.
Fermented tea is subjected to a forced blast or hot air from heaters in such a manner that the hottest air comes first into contact with driest tea. During this process, moisture equivalent slightly above half the weight of the drool (I.e the tea being processed) has to be evaporated.
The result then becomes the familiar black tea or made tea. To obtain the best result, an even spread of the dhool must be observed; a first through put of approximately 21 minutes should also be observed. The end moisture content in the dried leaf should be between 2.5% and 3%.
On the sorting or grading, Chiwar said the purpose is to obtain good appearance, liquor and size that would attract good market price. The dried leaves pass under series of fibre extractors onto a per-sorter.
The larger balls are separated and delivered to a crusher and the sifted leaf is further passed under series of fibre extractor onto the vibro screen which separates the tea to the final grades. The tea usually comes out in the following grades; Broken Pekoe(Bp), Pekoe fanning (Pf), pekoe dust ( PD), dust 1 (d1) and dust2 (d2).
The tea is then packed in bulk or in tea bagsof 25 kilogrammes cartons which is peculiar to the Mambila tea style.