Understanding Matcha Particle Size: Mesh, Measurement and Dispersibility

Mesh, particle-size distribution, agglomeration, dispersibility, suspension and dissolution answer different technical questions. Dispersibility describes observed dispersion performance under stated conditions, including the liquid, powder concentration, equipment, mixing time and endpoint. Treating these terms as alternative ways of saying “fine powder” creates false precision in a bulk matcha specification. Two reports can display convincing numbers while describing different sample preparation, measurement principles or result bases.

A useful particle-size discussion therefore begins with the method. It then separates dry-powder measurement from behaviour during incorporation and from the longer-term performance of the formulated product. Procurement needs a candidate that can be measured consistently and performs under the target equipment and formulation conditions, rather than an abstract fineness ranking.

Mesh Is a Sieving Result, Not a Particle-Size Distribution

Mesh terminology belongs to a sieving context. ISO 3310-1 sets technical requirements and test methods for metal-wire-cloth test sieves, while ISO 2591-1 describes factors that affect test sieving and the presentation of results. Buyer and supplier should agree the sieve method and acceptance criterion.

A complete mesh statement identifies the referenced standard or sieve system, nominal aperture, test procedure and the fraction passing or retained. Regional and industry conventions can also differ. A mesh-to-micrometre conversion describes an aperture; it leaves particle shape, the full distribution, agglomeration and liquid behaviour unresolved.

Sieving can still provide useful information when it is the agreed method. The specification should state what the result means and how it will be reproduced. A standalone label such as “high mesh” is not an operational specification.

Particle Size Requires a Distribution and a Measurement Context

A powder does not have a single particle size. A report may use a median, selected percentiles or a distribution width, and the result may be based on volume, number or another calculation basis. A USDA Agricultural Research Service page for a peer-reviewed matcha imaging study describes a series of D-values used to represent the distribution. This supports reading the distribution rather than reducing matcha to an unexplained average.

Measurement principle matters as well. The published scope of ISO 13320 explains that laser diffraction estimates a size distribution from light-scattering behaviour and reports the spherical-particle distribution that matches the measured pattern. It also notes that non-spherical particles can produce different distributions when methods based on other physical principles, such as sieving or sedimentation, are used.

Results obtained by sieving, laser diffraction, sedimentation or materially different sample preparation are not directly interchangeable and cannot be converted through a universal factor.

For a comparable matcha result, the measurement method, instrument, calculation basis, dispersing medium and sample preparation should accompany the reported distribution. Optical parameters and treatment used to break up the sample may also matter. Quality teams need to review results obtained under different methods before placing them in the same comparison.

Agglomeration Changes What the Instrument and the Process See

Fine particles can form clusters during storage, handling or contact with liquid. Sample preparation determines whether an instrument measures relatively separated particles or agglomerates that remain together under the chosen conditions. Stronger laboratory dispersion may produce a different distribution without changing the way powder first enters a factory mixer.

This distinction is central to processing. Initial incorporation depends on the liquid, powder concentration, addition sequence, equipment, shear and time as well as dry particle size. The specification should therefore keep the dry-powder measurement and the application dispersion test in separate fields.

Agglomeration can make clusters appear larger without changing the underlying particles. A favourable laboratory distribution still needs a separate factory dispersion check.

Dispersion, Suspension and Dissolution Are Separate Behaviours

Dispersion describes the incorporation and distribution of particles in a continuous phase. For matcha, the test sheet can include wetting, visible agglomerates, uniformity after mixing and the energy or time required to reach the target state.

Suspension concerns what happens to undissolved particles after incorporation: how the system changes during the defined observation period, the nature of any sediment and whether the product can be redispersed under an agreed procedure. These questions become part of the complete process and package evaluation for an RTD beverage.

Dissolution has a narrower physical-chemistry meaning: phases combine to form a homogeneous solution. Matcha contains finely milled leaf material. Some components can enter the liquid phase, while leaf solids remain particulate. A matcha milk tea study in the *Journal of Dairy Science and Technology* separately identifies incomplete dissolution and suspension in its particular beverage system. Other formulations require their own stabilisation and rheology work.

Descriptions such as “no visible large lumps”, “uniform immediately after mixing”, “slower settling during the observation period” and “no visible particles under the stated observation method” describe different observable states; none establishes complete dissolution.

Particle Size Is One Part of Performance

A 2003 processed-food study reported slower water sedimentation for its fine-matcha samples than for its normal sample, together with differences in selected food tests. The result shows a possibility within those samples and applications, rather than a universal relationship between smaller particles and better products.

Powder handling introduces another trade-off. A 2009 matcha study examined flowability across samples prepared by different milling and classification routes and found links with milling method, particle-size group, electrostatic behaviour and humidity. Factory teams therefore need to assess flow into feeders, dust generation, dosing and wetting alongside fineness; these properties may move in different directions.

Particle size can be commercially relevant without becoming a quality hierarchy. A useful specification connects the chosen measurement to the finished-product and line requirements.

Separate Measurement Control from Application Approval

Procurement and quality teams can separate measurement control from application approval in six steps:

1. Establish sample and lot identity.
2. Compare candidates using the same particle-size method and sample preparation.
3. Capture the complete distribution and calculation basis rather than an unexplained average.
4. Run a separate dispersion comparison under fixed powder concentration, liquid, temperature, addition sequence, equipment and time.
5. Note initial wetting and agglomeration separately from settling, the amount and character of sediment, redispersion and sensory texture.
6. Confirm shortlisted candidates in the actual formulation and process before application approval.

For RTD projects, this screen feeds into the full process, package and in-pack evaluation. For incoming-material control, the specification must identify the approved method, result format and acceptance basis. Particle-size measurement and application testing answer separate questions, so both remain in the project file.

Discussing Particle-Size and Dispersion Requirements with CHA STELLA

CHA STELLA can discuss candidate matcha samples against a defined application and review the particle-size information, dispersion conditions and finished-product observations relevant to that project. Selection remains tied to the target formula, equipment and approved comparison. Mesh designations and isolated particle-size values remain inputs to the comparison; performance in the finished product decides suitability.