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The fermentation process of black tea production technology Video black tea production method wilting process diagram

Published: 2026-04-02 Author: World Gafei

Last Updated: 2026/04/02, Unlike ordinary black tea, Darjeeling Tea's color is not black. It seems to be a combination of yellow, green and red tea. In particular, the first blush in Darjeeling is green. Its taste is also different from that of black tea. It is very similar to oolong tea. Why is Darjeeling Tea so special? In the past, it was thought that this was caused by the unique weather conditions and environment of Darjeeling.

Withering

Unlike ordinary black tea, Darjeeling Tea's color is not black. It seems to be a combination of yellow, green and red tea. In particular, the first blush in Darjeeling is green. Its taste is also different from that of black tea. It is very similar to oolong tea.

Why is Darjeeling Tea so special?

In the past, it was thought that this was caused by the unique weather conditions and environment of Darjeeling. However, with the increasing understanding of its processing process, we understand that Darjeeling Tea's processing process, especially the withering process, plays the most important role. The reason why Darjeeling Tea has such characteristics is because of its withering process. It is said that mastering the withering process is equivalent to managing 70% of the entire tea process. As mentioned earlier, Darjeeling has three different kinds of tea, spring picking tea, summer picking tea and autumn picking tea. Due to the great differences in water content, polyphenol content and composition types of tea, different processing methods are used in different seasons.

The plucked leaves spread a very thin layer of leaves on the withered tray, and the air blew from below. The bottom of the tray is a perforated plate, so the tea is blown uniformly.

Laying tea on a withered tray is a process called withering. Darjeeling Tea's withering process takes longer than ordinary black tea. Darjeeling's first flush takes 48 hours. Until the moisture content drops to about 30%. The retention time of withering was adjusted according to the initial water content of tea. For ordinary black tea, as long as it is Darjeeling Tea, there is no need to wither. The higher the moisture content, the more effective the subsequent fermentation. As a result, the tea turned black.

In the process of withering, internal enzymes are triggered and begin to mature. This is the same mechanism as hanging up immature pineapples to make them more mature. Another example is that hay is usually sweet, while grass is a very green fragrance that has just been cut. These all involve the same mechanism. This enzyme is caused by dehydration and mediates the process of moderate maturation. Ripening is a kind of oxidation or enzymatic hydrolysis to produce various volatile substances. In tea, these volatile compounds give the flower fragrance and flavor.

When I first walked into Darjeeling Tea's withering room, I thought I had come to an orchard! The room is full of rich and pleasant fruit aromas. Due to the long withering process, the water content of tea is low. As a result, Darjeeling Tea could not ferment effectively because the enzyme needed water to start full fermentation. Therefore, Darjeeling Tea's color is composed of red, yellow and green. Darjeeling Tea is semi-fermented tea to some extent, similar to oolong tea.

This process is called withering. Darjeeling Tea's withering process is much longer than that of ordinary black tea. Darjeeling's first flush takes 48 hours. Until the moisture content drops to about 30%. The retention time of withering was adjusted according to the initial water content of tea. For ordinary black tea, as long as it is Darjeeling Tea, there is no need to wither. The higher the moisture content, the more effective the subsequent fermentation. As a result, the tea turned black.

In the process of withering, internal enzymes are triggered and begin to mature. This is the same mechanism as hanging up immature pineapples to make them more mature. Another example is that it usually gives off a sweet smell, while the grass gives off a very green smell after it has been cut. These all involve the same mechanism.

This enzyme is caused by dehydration and mediates the process of moderate maturation. Ripening is a kind of oxidation or enzymatic hydrolysis to produce various volatile substances. In tea, these volatile compounds give the flower fragrance and flavor.

When we walked into the withered room, it smelled like an orchard! Due to the low water content of tea, Darjeeling Tea could not ferment effectively because the enzyme needed water to start fermentation. Therefore, Darjeeling Tea's color is composed of red, yellow and green. Darjeeling Tea is semi-fermented tea in a sense, similar to oolong tea.

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