Overview
ISO 8196-3:2022 (IDF 128-3:2022) specifies a harmonized protocol for the evaluation and validation of alternative quantitative methods of milk analysis. It is intended where classical interlaboratory studies (ISO 8196-1 | IDF 128-1) are not feasible-for example when only a limited number of operational instruments are available. The standard covers validation steps, performance criteria and a route to national and international approval for methods measuring milk parameters such as fat, protein, lactose, urea and somatic cells (and can be extended to other measurands).
Keywords: ISO 8196-3:2022, milk analysis, validation protocol, alternative methods, quantitative methods, milk parameters.
Key topics and technical requirements
- Two-phase validation protocol
- Phase I - Methods comparison study: Expert laboratory compares the alternative method against the reference method or a validated instrument under test-bed conditions; assesses performance characteristics.
- Phase II - Method confirmation study: Confirms precision and performance in routine testing conditions after successful Phase I.
- Performance characteristics and assessment: The protocol lists compulsory assessments and additional informative investigations, with guidance for statistical compliance.
- Roles and competence
- Expert laboratory: Qualified staff and equipment; should conform to ISO/IEC 17025 and have relevant experience.
- Organizing laboratory: Responsible for interlaboratory studies when applicable and for sample homogeneity checks.
- Approval principles: General principles for granting national and international approvals are established, based on the validation protocol.
- Supporting materials: Annexes contain measurement-process descriptions, indicative performance limits for raw milk, calculation examples and procedures (e.g., linearity sample preparation).
Practical applications and users
- Who uses it:
- Dairy testing laboratories developing or adopting alternative analytical instruments (e.g., milk payment analyzers, milk recording devices).
- Manufacturers seeking official validation/approval for new milk analysis instruments.
- Regulatory bodies and approval organizations evaluating methods for official use.
- Typical use cases:
- Validating a new instrument generation when only a few units exist.
- Demonstrating method accuracy, trueness and precision for routine milk testing (fat, protein, lactose, urea, somatic cell count).
- Supporting applications for national or international approval of alternative quantitative milk analysis methods.
Related standards
- ISO 8196-1 | IDF 128-1 - Analytical attributes of alternative methods (complementary)
- ISO 8196-2 | IDF 128-2 - Calibration and quality control in the dairy laboratory
- ISO/IEC 17025 - Competence of testing and calibration laboratories
This standard provides a practical, criteria-based approach to validate alternative milk analysis methods where full interlaboratory studies are impractical, enabling consistent approvals and reliable routine testing.