To begin with it is perhaps desirable to define "Tea". "Tea" has been clearly defined in the Tea Act,1953. As per provision of Tea Act, "Tea" means the plant Camellia Sinensis (L) O. Kuntze as well as all varieties of the product known commercially as tea made from the leaves of the plant Camellia Sinensis (L) O.Kuntze including green tea. Tea which is available in the market is in fact "Made Tea". Green leaves plucked from the tea bushes are manufactured into "Made Tea" or "Tea" in the Tea Factories through a series of manufacturing process.Green leaves, in the process of manufacturing "Made Tea" or "Tea" also generates by-product known as "Tea Waste". This "Tea Waste" is unfit for human consumption and has two uses viz.
i) for manufacture of caffine
ii) for using as manure in the tea field.
Made tea or Tea manufactured from green tea leaves is generally classified into two types viz. Black Tea and Green Tea. Green tea is different from Black tea since fermentation of green leaves is arrested in manufacturing green tea. Again black tea is of two types viz. Orthodox tea and CTC tea. Orthodox teas are manufactured with the help of orthodox roller in the process of rolling while CTC machine/Rotervan is used in rolling process in manufacturing CTC teas. CTC stands for Crushing, Tearing & Curling. While, most of the teas produced in Sri Lanka is of "orthodox" variety, Kenya produces mainly CTC teas.
The tea processing in any factory in the traditional way comprises the following phases
1. Withering
2. Rolling
3. Fermentation
4. Drying
5. Sorting & Grading
Apart from Orthodox, CTC & Green tea, powder tea which is known as “Instant tea”: is also being manufactured in India and in few other tea producing countries of the world like Kenya and Sri Lanka. The Instant tea is manufactured in separate factories known as Instant tea factory. The procedure for manufacturing Instant tea is different from that of black tea or green tea. The raw materials used for manufacturing Instant tea are green tea leaves and/or tea waste. The manufacture of Instant tea in India has started since 1960.
Tea, mainly the black tea is also being further processed with the help of tea bagging machine to manufacture "tea bags". This is one of the “convenience” tea generally preferred by the consumers of the western countries. “Filter papers” is being used as packaging material for manufacture of tea bags.
Instant tea and Tea bags are generally known as "convenience tea" since these are convenient for consumers to get the liquor with less hazards. Moreover, in order to preserve the quality of tea during its different stages of trading activities particularly in retail trading and also to maintain the uniformity of the quality to the extent possible, black tea or green tea are packeted either in original form or in blended form in small consumer packs. These are known as "Packet tea". So tea planters at the garden level, after manufacture of "made tea" from green tea leaves, use bulk containers or small containers for packaging. Bulk containers are generally consists of wooden tea chests, polyline jute bags, multiwall paper sacks etc. and can contain 25 kgs. to 55 kgs. of tea depending on the nature or size of the container. Small containers consists of paper sacks, wooden box, metal caddies, polythene packs etc. and can contain 2 gms. of tea to 1 kg. tea according to the need of consumers and based on suitability to its handlings. Tea in bulk, after coming out from the estate is also packed or repacked in small containers by merchant packers apart from its "sale" in loose form to the consumers.As already mentioned, green tea leaves plucked from the tea bushes when manufactured in the tea factory through a series of tea processing like withering, rolling, fermentation, drying etc., converted into made tea. Depending on the system of tea processing, tea is classified into black tea and green tea. Black tea is obtained by so called fermentation process where as for making green tea fermentation is prevented. The characteristic of the beverage like tea is determined by the major components of the leaf i.e. polyphenols, the peptic substances, the flavouring constituents and caffeine. The caffeine is known for its stimulating effect.
Quality of "made tea" or "tea"
The term "quality" in its broadest sense is used as a description of all the characters of tea by which it is judged on its market value. So quality means the summation of the desirable attributes comprising internal and external characters like aroma/flavour, strength, colour, briskness and character of infused leaf. The “quality” of the tea conforming to the specification laid down in the PFA Act may vary. The quality of tea also varies between garden to garden and also between the teas manufactured at different times -in a particular garden. The green tea leaves of the plant belonging to the species of Camellia Sinensis has its natural "aroma". The efforts of the tea manufacturer is generally aimed at to maintain the natural aroma in the made tea as far as possible.
The quality of "tea" depends primarily on the nature and chemical composition of the plucked leaf which is again dependent on the type of bush, the growing conditions and the kind of plucked leaf like coarseness and fineness etc. Only careful and proper processing will bring out the full potential of the green leaf.
Each of the characteristics on which tea is assessed by trade is affected by one or more the factors involved both in the field and in the factory. Since a variety of factors plays a role and the production of a particular character is usually obtained at the expense of another, pre-processing and processing conditions is generally adjusted as to bring about the most desirable characters in a tea made from a given material.
So the factors affecting tea quality apart from those involved in processing can be distinguished in 3 groups viz. genetic, environmental and cultural.
(i) Tea quality is primarily determined by the genetic properties of the tea planting and those of the tea bush in particular.
(ii) Both soil and climate are influencing the quality of tea. Climatic condition including temperature, humidity, sunshine duration, rainfall are important in determining quality.
(iii) Field operation like pruning, fertilising, shading, plucking round and plucking standard are also playing the important role in determining the quality of tea.
Tea Tasting
Like any other industrial product, tea is also assessed for its quality and value. This is being done in the first instance, by the tea maker in the factory to ensure of the quality of the product and to prevent defects if any.
The made tea of an estate, is also tested by the commercial tasters (generally known as broker) for determining the quality and its value. The term "taste" is used here in its general sense and includes aroma.
Tea tasting is aimed at describing and evaluating teas in the form of individual grades or as blended product. The description and evaluation include the appearance of the dry tea, of the infused leaf and of the infusion obtained by brewing the tea with boiling water, the taste characteristics of the infusion, commonly called the liquor, etc. During tasting the various characteristics that make up a tea liquor viz. briskness, strength, colour, body, quality and aroma or flavour, are assessed individually.
In assessing the characteristics of a tea the taster first examines the dry tea for colours, uniformity, twist, tip and aroma and then passes on to the infused leaf. Ideally, this should be of a bright copper colour and substantially devoid of the green tinge of unchanged chlorophyll. From the colour and evenness of the infused leaf the taster forms his opinion about the quality of the fermentation. The brightness of the infused leaf is correlated with brightness of liquor and both are indicative of briskness.
