Halfway through my Japan Tea Tour in May, we visited a large matcha processing facility in Uji (south of Kyoto). If you haven't had matcha before, it's a powdered tea that is used in Japanese tea ceremonies. Recently, there's been a "matcha boom" in the US as health conscious consumers add it to their smoothies, baked goods, lattes, etc. There are various grades of matcha, including culinary and ceremonial, and on our tour we were able to see the different processing methods.
In order to increase the flavor and color of the tea leaves, the tea plants used for matcha are cultivated in the shade for about two weeks before harvesting (picture to the right shows the tarps shading the tea bushes).
Here are two grades of tencha, the tea leaves used for matcha (picture to the left). The darker green on the right will be used to make ceremonial (higher) grade matcha and the lighter green on the left will be used to culinary matcha (cooking and baking).
The culinary (lower) grade matcha is ground and pulverized by ceramanic balls in a large machine. Whereas, the ceremonial (higher) grade matcha is ground into powder between two granite disks (picture to the right). There were at least a dozen of these grinders working 24 hours a day. We all had to wear lab coats, hair nets and masks, plus have all dust blown off us, to enter the matcha factory. Making matcha is serious business!