A Stone Mill Produces 40 g an Hour

The final step in making matcha is grinding tencha on a stone mill. It is remarkably slow.

Roughly 40 grams per hour. Producing a single 300 g package takes about seven and a half hours of continuous milling.

Why not speed it up

Heat.

Faster grinding generates friction, and friction produces heat. Heat drives off volatile aroma compounds and degrades the green pigment. Everything gained by shading the field for weeks would be lost in the last step.

So the mill turns slowly and steadily. Inefficient, but it reduces leaf to an extremely fine powder without cooking it.

How fine is fine

Matcha particles run around 10 microns. Better grades reach 1 to 5 microns.

	Particle size
Wheat flour	30–60 microns
Typical powdered tea	20–50 microns
Fine matcha	1–5 microns

An order of magnitude below flour. Rubbed between your fingers, good matcha feels closer to silk than to powder.

Particle size becomes mouthfeel

Matcha does not dissolve. Ground leaf particles suspend in liquid, so their size translates directly into texture.

Coarse feels gritty. Fine feels smooth and integrated.

Finer powder also disperses more readily and clumps less. As particle size drops, perceived roundness and body increase while bitterness and astringency recede.

The same leaf, milled differently, produces a noticeably different drink.

Machine milling

Mechanical grinding is far faster and handles much larger volumes.

The trade-offs are heat and a coarser result. For matcha destined for baking or blending into other foods, that is fine — the difference disappears in the finished product.

For something you drink directly, it shows.