Overview
ISO 9877:2026 - Milk and milk products - Determination of ash, establishes a standardized methodology for measuring the ash content in a wide range of dairy products. The ash content reflects the total mineral residue remaining after incineration, serving as an important indicator of product composition and quality control. This international standard, jointly developed by ISO and the International Dairy Federation (IDF), aims to harmonize laboratory procedures, ensuring accuracy and comparability across the dairy industry.
Applicable Products:
- Milk (whole, partially skimmed, skimmed)
- Milk powder
- Whey powder
- Whey protein concentrate
- Infant formula
- Milk permeate powder
- Milk protein concentrate
Note: For caseins and caseinates, the fixed ash determination is covered separately in ISO 5544 | IDF 89.
Key Topics
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Scope and Purpose:
ISO 9877:2026 offers a uniform method for determining ash content by incineration, facilitating reliable assessments of mineral content in dairy products.
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Definition of Ash:
Ash is defined as the residual mineral substances after a sample is incinerated in air. It is expressed as a percentage by mass relative to the original sample quantity.
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Principle and Methodology:
- Samples are incinerated at 550 °C ± 25 °C.
- The remaining residue (ash) is quantified gravimetrically.
- Special equipment such as high-precision balances, electrical furnaces, and suitable crucibles are essential for accurate measurement.
- Both manual and automated (thermogravimetric analysis) techniques are permitted.
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Precision and Repeatability:
- Intricate attention to sample preparation and weighing ensures repeatable, reliable results.
- Interlaboratory studies have validated the procedure’s repeatability and reproducibility for key dairy matrices.
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Sampling Requirements:
- Although sampling itself is not detailed in this document, it is critical to use representative, unaltered samples, in line with ISO 707 | IDF 50.
Applications
ISO 9877:2026 is vital within the dairy industry, laboratories, and regulatory environments for several reasons:
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Quality Control:
Determining ash content helps monitor the mineral composition of dairy products, ensuring product consistency and verifying label claims.
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Production and Processing:
Ash content measurements are crucial in dairy product formulation, particularly for milk powders, infant formula, and protein concentrates where mineral content impacts functional and nutritional properties.
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Compliance and Trade:
Adoption of the ISO 9877:2026 standard facilitates regulatory compliance and international trade by enabling consistent comparison of analytical results across borders.
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Research and Development:
Food scientists and developers utilize ash determination to fine-tune recipes and study the effects of processing on mineral retention in new dairy products.
Related Standards
For comprehensive quality assurance in the dairy sector, consider the following associated standards:
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ISO 5544 | IDF 89:
Caseins - Determination of “fixed ash” (Reference method)
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ISO 707 | IDF 50:
Milk and milk products - Guidance on sampling
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ISO 5725-2:
Accuracy (trueness and precision) of measurement methods and results - Guidance on repeatability and reproducibility
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AOAC Official Methods Program:
Guidelines for validating collaborative studies of analytical methods
By implementing ISO 9877:2026, laboratories and producers benefit from robust, precise, and internationally recognized procedures for ash determination in milk and milk products, strengthening both internal quality protocols and market credibility.