The first teabags used here in the U.S. were around 1903 and were made of silk. They were meant to be small samples, to be cut open and the tea inside steeped loose in the teapot, but people kept the tea in them and steeped them. The convenience was alluring. Grinding the processed tea leaves to a fine dust made the tea easier to load into these little bags. Soon they were being made of other materials such as a plant-based fabric. This dust is with us today but should not be confused with a premium tea from Japan called Matcha. The difference is significant.
|Top: Matcha, Bottom: Black dust tea|
Dust tea is produced purposely as a way for the tea not only to be bagged but also to steep up fast and strong. There are three grades:
- D1 (Dust 1) which is from Sri Lanka, Indonesia, China, Africa, South America, and Southern India.
- PD (Pekoe Dust)
- PD1 (Pekoe Dust 1) which is mainly produced in India.
“Pekoe” is a term that refers to China. It was adopted by the Dutch in the late 1600s when they started bringing tea to Europe. The dust is made by machine where the processed leaves are ground down. The particle size, though, is not nearly as fine as what’s in matcha.
The tea leaves used in making matcha are the same as those used for gyokuro. They are grown in the shade during the last 14-20 days before being harvested so that the growth is slowed, chlorophyll is increased, and amino acids such as L-Theanine are more prominent. The tea is harvested by hand, with skilled workers selecting only the best buds, which are then rolled out and dried, creating gyokuro (jade dew) or being crumbled into tencha that then has the veins and stems removed. The remaining parts of the leaves are ground by stones (as much as one hour to grind a mere 30 grams) into the familiar talc-like powder known to matcha lovers everywhere. Ceremonial Grade Matcha, grown 10 days longer in shade, comes from the Nishio Region of Japan. Most of the high-quality matcha tea is grown in the Uji Tawara vicinity. The particle size is measured in how many holes per square inch there is in the sifting screen (1000 mesh is a particle about 0.013 millimeter in diameter).
Compared to matcha, dust tea particle size is like a boulder compared to a tiny pebble on the beach. This mean that matcha can be consumed with the water where dust tea is usually gritty feeling in your mouth. You can really feel the difference. This is also why matcha makes such a good ingredient in cooking.
UPDATE: From Ian Chun of Yunomi.US
The basic process is: shade the leaves for 3-4 weeks. (2 weeks makes kabusecha, 3 weeks makes gyokuro, although there are other cultivation differences). While it’s nice to say that it is picked by hand, usually it’s not.
The leaves are then steamed and dried without rolling (rolling would turn it into sencha). The result is very flaky, and called tencha. Stems and dust are removed (you don’t really get veins since the leaves are generally younger so soft to begin with).
At this point you could grind it into matcha. The best matcha would be harvested in the spring, then aged as tencha until November or so. This reduces the amount of catechin even more (in addition to the shading) making it even less bitter.
For lower grades it would be a summer or autumn harvest, and they might use a drum mill or ball mill that crushes the leaves in bulk rather than a traditional stone mill. (By the way the best stone mills are machine-operated and have a coolant systems built in to eliminate heat from damaging the leaves.)