THE SCIENCE OF TEA
The fact that people all over the world can agree on a question of taste is indeed a true rarity. Tea is one of these exceptions – people are highly committed to celebrating and drinking tea across all cultural areas.
For the production of both black and green tea, the identical leaves are processed. The quality and the taste of each type of tea is shaped by the cultivation area, the altitude, the climate, the type of the plant as well as the special care during the harvest and the processing.
In order to make the freshly picked, still green tea leaves smooth for the rolling process, the leaves are aerated on grids for several hours. The now withered tea leaves are then rolled, eventually breaking the tea leaves into small pieces. During this process, the cell sap leaves the leaf and reacts with the oxygen from the air. The fermentation process starts giving it the typical golden-yellow, red-brown colour and black tea taste.
When the optimal degree of fermentation is reached, the leaves dry and the fermentation process stops. By sorting the tea leaves, the manufacturing process is completed. The dried cell sap, which has a stimulating effect, will unfold by infusing the tea leaves and turn it into a delightful beverage in one’s cup.
The typical leaf grades of black tea define the quality of each tea.
Different to the production of black tea, the tea leaves are heated up after the withering in the manufacturing process of green tea. Due to the heating, the pores of the tea leaves close and the fermentation process is being suppressed. After cooling down, the leaves are rolled and dried in the oven until a small proportion of water is left. This gentle processing maintains the natural ingredients and the delicious taste of the tea leaves.
To differentiate the quality and texture of tea, the leaves can be classified into four leaf grades.
While the valuable, handpicked Leaf Tea consists of whole tea leaves, the Broken Tea leaves are shredded mechanically, giving the tea its special and intense aroma. Fanning Tea as well as Dust Tea is, because of its fine texture, mostly used for filling tea bags and is known for its strong aroma.
The two most important factors in order to ensure an outstanding taste experience of tea are the infusion time and the water temperature.
For the optimal infusion of tea, the boiled water needs to be cooled down to circa 80°C. The perfect infusion time is, depending on taste and type of tea, 1 ½ to 2 minutes. Green tea may be used 2 to 3 times, depending on its quality. The higher the quality the more infusions are possible. After the first infusion, the water should be hotter for the next usage. The infusion time will now be approximately 1 minute. The tea leaves should not dry out between the infusions.
Black tea should be brewed with a water temperature of approximately 95°C for ideally 2 to 3 minutes – not longer than 5 minutes. In the first 3 minutes the tea gets a stimulating effect. After that, this effect is inhibited by the released tannins. After 5 minutes, the tea develops a bitter taste.
The water temperature should also be approximately 95°C – but a lower temperature will also do. Fruit tea should brew at least for 5 minutes in order to enable the dry fruit to release its flavour.