Bulk analysis

Definition and purpose

Bulk analysis testing assesses the mechanical properties of particulate materials as a collective whole, rather than analysing individual particles. This includes powders, granules, pellets and similar materials. The focus is on how a sample behaves in bulk, under conditions that replicate real-world usage or processing environments.

The results help verify flow characteristics, compressibility and overall strength. Bulk testing supports the development of materials that maintain their integrity under stress, dispense correctly, and meet desired texture profiles.

Common material types

Materials commonly assessed through bulk analysis include rice grains, pharmaceutical powders and excipients, catalyst pellets, freeze-dried products, and cosmetic powders. Each of these presents unique challenges relating to texture, flow and stability. Bulk testing enables engineers and researchers to quantify these behaviours and optimise performance.

Key parameters measured

Bulk testing evaluates several mechanical characteristics:

• Firmness refers to a material’s resistance to deformation under applied force.
• Adhesiveness measures how strongly the material clings to surfaces or itself.
• Shear resistance evaluates how well the material withstands forces that cause internal sliding.
• Compressibility describes how easily a sample compacts under pressure, and bulk density captures the mass per unit volume, including any void spaces within the sample.

Compression testing

Compression testing is used to assess how materials respond when compacted. It is particularly suitable for rigid or semi-rigid samples such as tablets, powder plugs or catalyst pellets. This method helps determine deformation resistance, fracture strength and how volume changes under pressure.

Motorised force testers such as the OmniTest and MultiTest-dV series from Mecmesin deliver reliable, repeatable compression testing. These systems apply controlled forces and collect detailed data on material behaviour throughout the test cycle.

Shear testing with Kramer shear cell

For softer or more cohesive samples such as cooked rice, pet food or formulated snacks, Kramer shear cell testing is an effective method. A series of parallel blades shear through the material, simulating mechanical stress the product might experience in use.

This testing measures the force required to shear through the sample, the extent and nature of its fragmentation, and how much material adheres to the blades or test cell. In food research and development, where texture directly affects consumer perception, these results are especially valuable.

Industries and products

Bulk testing is relevant to a wide range of industries. In food and beverage, it is used to test cooked rice, cereals, powdered drink mixes and pet food. In pharmaceuticals, it helps optimise powder blends and support tablet formation. Chemical and adhesive industries assess catalyst pellets, resins and powdered reagents. Cosmetics manufacturers use bulk analysis to ensure the performance of loose powders and compacted formulations. In agricultural, it is relevant to testing seed coatings, animal feed and fertilisers.

Case study – catalyst pellet crush testing

Catalyst pellets must maintain their shape and strength in demanding chemical processes. If they fracture, they can produce dust and clog reactor systems, reducing overall process efficiency. Compression testing of bulk samples verifies mechanical robustness, helping manufacturers produce consistent, durable products for use in catalytic systems.

Case study – cooked rice texture analysis

The texture of cooked rice is a critical factor in both product appeal and application. Using Kramer shear cell testing, engineers can measure key properties such as firmness and adhesiveness. These insights support formulation improvements and quality assurance processes that maintain texture consistency across production batches.

Applicable standards and protocols

To ensure consistency and regulatory compliance, bulk testing is often carried out in accordance with established standards. These include:

• ISO 13299 - which provides guidance on texture profile analysis across both food and pharmaceutical applications.
• ASTM D6128 - specifying procedures for measuring the bulk density of powders using a Scott Volumeter.
• ISO 11607, which outlines packaging requirements for terminally sterilised medical devices, including materials that contain particulate fills.

These standards help laboratories and manufacturers produce valid, repeatable test results.

Best practices for compliance

Accurate testing requires more than the right equipment. Key practices include regular calibration against certified weights or force references, consistent sample preparation under controlled temperature and humidity conditions, and maintaining a documented data trail for quality audits. Integrating software such as VectorPro supports automated analysis, pass/fail decision-making, and the generation of audit-ready reports.

Expert engineering and equipment

Mecmesin systems are designed for precision and reliability in bulk testing applications. The OmniTest offers fully automated texture and compression testing with comprehensive analysis options. The MultiTest-dV is a flexible, motorised tester ideal for particulate compression. The Kramer Shear Cell is designed specifically for testing soft or cohesive bulk samples such as food products.

Each system enables consistent test routines and delivers data that engineers can use to make informed decisions quickly.

Adaptable fixtures and jigs

Bulk samples vary widely in shape, fragility and volume. Mecmesin provides an extensive selection of fixtures, grips and test jigs, many of which can be customised to suit specific test materials. Whether analysing irregularly shaped catalyst pellets or delicate freeze-dried powders, fixtures can be configured to protect the sample while delivering accurate results.

Global support and calibration services

Mecmesin supports its test systems with international service, calibration and training programmes. Engineers have access to maintenance services, software updates and application support, helping ensure tests remain compliant and aligned with operational goals. This is particularly important in regulated industries such as pharmaceuticals, healthcare and food production.

Need help selecting the right test method or equipment for your material? Mecmesin specialists are available to advise on setting up effective bulk analysis routines. Whether you're refining an existing process or developing a new product line, we can help ensure your testing is accurate, repeatable and aligned with industry requirements.