Production Methods: From Leaf to Matcha Powder

Matcha production is a linked sequence in which cultivation, rapid stabilization, cleaning, milling, and protective packaging all shape the final powder. The process does not begin at the grinder: farmers first alter leaf growth through shading, then processors work quickly to preserve the picked material before it becomes tencha and, finally, matcha.

Shading changes the leaf before harvest

The packet describes tea plants being covered with tana structures for 20–30 days before harvest, blocking 90–95% of sunlight. Under those conditions, chlorophyll production rises and the balance of leaf constituents changes. The covered fields are also reported to run 2–3°C cooler, slowing growth. Together, these effects support the green color and amino-acid-rich, umami-oriented character sought in matcha.

This stage distinguishes matcha-bound leaf from ordinary unshaded green-tea material. Shading must happen while the leaf is still growing; it cannot be recreated later by grinding or packaging. It is therefore a cultivation decision with consequences for every later production stage.

From picking to stable tencha

For selective harvesting, the packet identifies the terminal bud and top two leaves as the target. Hand picking can avoid bruising and exclude older growth, while mechanical harvesting is much faster but less selective. The intended grade and production scale help determine which method is practical.

Speed after picking matters because fresh leaves remain enzymatically active. The packet gives a 3–4 hour window for delivery to processing and describes steaming at 120°C for 20 seconds to stop that activity. Too little steaming can leave oxidation underway; too much can flatten the leaf’s character. Later processing cannot fully reverse damage that occurred while harvested leaves waited.

Unlike sencha, the steamed leaves are dried flat rather than rolled. The packet describes air drying at 180°C, followed by air separation that removes stems and veins. It reports that careful cleaning can remove 60–70% of the original leaf weight, leaving the soft leaf tissue called tencha. Tencha is not yet matcha: it is the cleaned, dried material prepared for grinding.

Slow milling turns tencha into matcha

Granite stone mills rotate slowly to limit heat while reducing tencha to particles reported at 5–10 microns. The packet gives a typical rate of 60 revolutions per minute and only 30–40 grams of powder per hour, with milling temperature kept below 25°C. The purpose of this low throughput is consistency without the heat associated with faster grinding.

Consider a producer who needs 300 grams of stone-milled matcha for a small release. At the stated output, one mill would require roughly 7.5–10 hours of grinding, before allowing for setup or cleaning. That simple example explains why milling capacity can constrain production even when plenty of tencha is available. An industrial ceramic grinder may produce far more per hour, but the packet warns that its higher heat can introduce burnt notes and damage heat-sensitive qualities.

Quality control and packaging

Before release, trained sensory panels assess color vibrancy, aroma complexity, and taste balance. The packet also describes laboratory checks for L-theanine, catechins, caffeine, and particle-size distribution. These measurements address different questions: sensory review judges how the matcha presents in the cup, while laboratory analysis checks composition and milling consistency.

Finished powder is then placed in nitrogen-flushed containers. Replacing oxygen slows oxidation, helping protect green color and delicate flavor during storage. Packaging is thus part of production quality, not a cosmetic final step.

Common process confusions

Tencha and matcha are related but not interchangeable: tencha is the de-stemmed, de-veined leaf material; matcha is the fine powder made by milling it. Shading is cultivation, steaming is stabilization, and grinding is particle reduction. A producer can perform one stage well and still lose quality elsewhere, so claims such as “stone-ground” describe only part of the chain. Cultivar, first-flush timing, shading, harvest selection, tencha cleaning, milling, testing, and oxygen-conscious packaging belong together when evaluating how a matcha was made.