This is the method of producing sencha (Japanese green tea), which originated in Kakegawa City, Kikugawa City, and Makinohara City.
The central region of Shizuoka Prefecture has a warm climate with strong sunlight, which resulted in tea leaves that were hard and had a strong astringency.
To overcome this issue of astringency, tea farmers developed the deep steaming method.
By extending the steaming time, the bitterness is reduced, resulting in a smooth, rich flavor, and the tea takes on a deep green color.
Additionally, since the tea leaves become finer, nutrients that are difficult to dissolve in water can also be consumed.
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