Particle Distribution: Understanding Matcha Powder Sizes

More than an average particle size

Particle distribution describes the spread of sizes within matcha powder. Two samples can share a median diameter yet have different proportions of fine and coarse material. The complete distribution therefore gives information that a single “average micron size” cannot.

Keep particle size separate from commercial grade. A narrow distribution does not certify “ceremonial” matcha, and there is no grade table established by the research cited here that places every drinking matcha in one size range and every culinary powder in another.

How laboratories describe the distribution

Laser diffraction estimates particle sizes from scattered light. In the cited matcha milling study, the powder was dispersed in medium-chain triglycerides and measured by laser diffraction. The authors reported relative particle volume at each diameter and used microscopy to examine the particles. The measured distribution was not simply a count of particles seen under a microscope.

• Dv10: the diameter below which ten percent of the measured particle volume lies.
• Dv50: the volume median, with half the measured volume below that diameter.
• Dv90: the diameter below which ninety percent of the measured volume lies.

Malvern Panalytical explains these as cumulative-volume percentiles. The “v” matters: a volume-based percentage is not the same as a percentage by particle count. A D60 value also needs a stated basis and method. Do not treat an unreferenced D60 threshold as a national matcha standard or a universal quality benchmark.

Surface area: the correct relationship

For ideal spheres of equal density, surface area per unit mass is proportional to the inverse of diameter. Halving the diameter doubles that specific surface area; it does not quadruple it, and the increase is not exponential. This is a simplified geometric model, not a measurement of real matcha particles.

Real powders have irregular shapes and may form agglomerates. Those details affect how much surface is accessible to water. The simple model explains why size can matter, but it cannot predict the taste of a powder from diameter alone.

What matcha research actually shows

The cyclone-, bead-, and stone-milling study used leaves from the same Okumidori harvest batch. It found differences in physical properties, chemical release and stability, and sensory perception. The researchers reported that smaller particle sizes increased the release of various taste components but also increased losses of some polyphenols.

This is evidence for interactions between physical and chemical properties, not a rule that smaller is always better. It also does not establish stone milling as universally more uniform than other methods. A claim about a particular mill needs that mill’s measured result, not just its name.

Texture and preparation

Particle characteristics are relevant to mouthfeel and dispersion, but an exact grittiness threshold for every drinker cannot be inferred from these sources. Nor can foam persistence identify a unique distribution: the milling research treats physical properties, composition, and sensory attributes together rather than as a single quality switch.

Sifting helps break up clumps before preparation; it is not equivalent to measuring a laboratory particle-size curve. A powder can consist of fine primary particles that collect into larger clumps. Marukyu Koyamaen explicitly notes that fine matcha can clump and recommends sifting for easier mixing.

Questions to ask about a specification

• Is the result by volume, number, or another basis?
• Which instrument and dispersion medium were used?
• Are the median and coarse tail both reported?
• Does the report identify the tested batch and explain sample preparation?
• Is a claimed grade limit linked to the exact standard, edition, and product category?

At home, compare texture using the same recipe and mixing method. Record what you notice, but do not turn a finger-rub test or sediment in a bowl into a micron measurement or proof of inferior leaf quality.