White tea is a special type of tea that until recently was only produced in China, nowadays white tea comes from countries such as India, Vietnam and Sri Lanka. The picking of the white tea is always manual and only the leaf buds and upper leaves are picked. The leaves should not bruise, otherwise, oxidation could take place, and that is not allowed with this type of tea. After picking, the leaves are dried in a room with a temperature of 30ºC and a low humidity. When the humidity is reduced by about half, the tea leaves are carefully dried in a wok or oven at a temperature of 40ºC until the moisture has dropped to 5%.
The name white tea comes from the fine white downy hairs with which the first leaves are covered. The tea has a subtle taste in which sweet and floral notes can be distinguished.
Green tea is not oxidized, to ensure that this oxidation does not happen, the freshly picked leaves are baked as quickly as possible at 250ºC. This baking can be a few seconds but can take up to 15 minutes. After baking, the leaves are dried until the moisture in the leaves is about 50%. The tea leaves are now supple and soft and they can easily be rolled up, curled, smoothed or compressed into pellets. To ensure that the moisture in the tea reaches 5%, it is further dried. The geographical location of the plantations largely determines the aroma of the tea.
Yellow Tea, like green tea, is not oxidized but gets an extra step in the processing process. After steaming, the leaves are slowly and lightly steamed before they are placed under damp cloths. The leaves can thus absorb their natural aroma again. During this process, the sweetness and smell of the tea become stronger.
Oolong tea is partially oxidized. The process starts with the wilting of the tea leaves until the moisture is reduced to 50%. In order to ensure that only the edges of the leaves are bruised, the leaves are shaken in baskets. After the leaves have oxidized briefly and reached the right level of oxidation, the leaves are dried in an oven to a moisture content of 5%. Oolong tea varies from light oxidized, about 30%, to an oxidation of 80%. Oolong tea with an oxidation of 80% tastes more powerful than black tea because Oolong always consists of full leaves.
Black tea is fully oxidized and gets four treatments. First, the moisture in the leaves is reduced to 50%. By placing the leaves on a conveyor belt and blowing warm air through them. The leaves are then broken by crushing them between two horizontally abrasive surfaces. This bruising causes moisture, leaf sap, to come out of the leaves. This, in turn, causes the tea to oxidize, giving the tea the black colour and typical taste and aroma. The leaves are transferred to an oxidation chamber, where the tea continues to oxidize between one and four hours. When the optimum oxidation has been achieved, the leaves are dried back to a humidity of 5%. Drying stops the oxidation process. From 100kg leaves, 5kg of tea remains.