Teh tarik is prepared from black tea harvested from the evergreen shrub, Camellia Sinensis. After harvesting, the tea is crushed. Crushing the tea leaves releases enzymes in the tea leaf cells, which reacts on the tea leaves; and develops the distinctive flavour of the tea and turns it dark. The flavour of the tea depends on the degree of fermentation, which is carefully controlled by heating and drying which deactivates the enzymes.
The components of black tea are highly complex, but the main components are caffeine, thobromine theophylline and xanthine which are stimulants and polyphenols. The astrigency and flavours in tea comes from polyphenols, which can make up to 40% of brewed tea. It is believed that the main health benefits of tea comes from the polyphenols, which are strong anti-oxidants and can reduce damage from free redicals on the human body.
Like coffee, tea comes in many grades and prices may vary from USD100 per kg for the best China black tea to as little as USD2 for low grade lowland tea harvested mechanically.
Tea quality depends on many factors, but the main ones are :
- Elevation of tea plantation above sea level
- Soil conditions
- Harvesting methods
- Processing and fermentation
The soil conditions and nutrients determine the concentration of desirable components of the tea. At high elevation, tea grows more slowly and the desirable flavours are therefore concentrated, as compared to lowland tea. Highland teas are also smoother and more aromatic.
Harvesting of the tea is also of primary importance. For best quality tea, only the top 2.5 to 5 centimeters of the plucked tea are the new and tender leaves of the tree, known as ‘Flushes’. Best quality tea is from specific plantations at high elevations, and the ‘Flushes’ are carefully selected and plucked by hand. On the other extreme, we have cheap lowland tea where mechanical harvesters lopped off the top of the trees, including branches to produce so called tea.