All kinds of teas are actually the leaves of the same single plant, Camellia sinensis. Ever wondered then why or how they are so different by the time they make it to our cup? We’ll Solve the mystery for you!
The difference between Black tea, Green tea, White tea or any other variety of tea lies solely in its processing. The leaves are generally picked by women farmers, owing to the fact that they are more delicate and manage to pluck the ‘two leaves and a bud’ keeping them intact. The processing after that differs, a quick over view of which is given below.
1) BLACK TEA
The processing of black tea all over the world is generally carried out it five major steps with minor variations.
The main aim of this process is to reduce about 30% of the moisture content of the leaves.
This can either be done naturally, by spreading the leaves on jute bags and covering them with nets. It takes about 14-18 hours to achieve the desired moisture level. Or the process can be speeded up by using artificial blowers to blow warm air over the leaves. This reduces the process time to about 8-10 hours.
After withering, the leaves are transported to rollers or press spindles. The leaves crushed between the rollers have their cells burst open and undergo the process of oxidation when exposed to air. The torn crushed leaves are sieved to separate out the ribs and veins from them. And only remains are further processed. This is also often called the CTC method or the Cutting- Tearing- Curling method.
This process starts with the rolling itself. After rolling however, the leaves are spread out on large boards in a room with a controlled temperature of about 40oC. It is in this process that the leaves start taking up their copper-red to brown colour and unfold their aroma. This process takes about 2-3 hours.
The leaves are transported to driers where they are held for about 20 minutes at 80-90oC till the moisture content drops to about 5-6%. The heat makes the cell fluid stick to leaves, giving tea it’s brown-black colour.
The dried cooled leaves are then sieved and sorted according to their size, which determines their quality. These leaves have a dark brown colour and can taste anything from fine flowery to full aromatic and strong. It can be infused with the desired aroma too.
2) GREEN TEA
The Japanese method of processing green tea has now been adopted widely throughout the world. This process includes the following steps:
In the same ways as those followed in the processing of Black tea, the leaves are dried to reduce their moisture level by upto 30% in around 10 hours.
This step is where the difference in processing lies. The leaves are transported to a rotating drum and steam is added to the drum. After about 2 the steam is realised. The quantity of steam in the drum needs to be carefully monitored. Too little steam induces fermentation while too much of it spoils the leaves.
Leaves are transferred to wooden drums and subjected to warm air (approximately 50-55OC). The leaves are constantly agitated with rotating forks to prevent lump formation. This process decreases the moisture content of the leaves by another 50%.
After drying, the leaves are rolled under differing pressure for about 10-15 minutes.
The leaves are dried once again, till the final moisture content drops to 4-5%.
Some processing units incorporate a polishing method, which involves pressing leaves against a hot plate making them flat and giving the extra glow. This step though isn’t mandatory.