Protein analysis helps food, dairy, ingredient, and animal feed producers understand the protein content of their products.
Protein testing is commonly used to support nutritional labelling, product specifications, quality control, regulatory requirements, customer assurance, and routine production monitoring.
AsureQuality offers protein analysis using the Kjeldahl method, an internationally recognised reference method with a long history of use across the dairy, food, cereal, and animal feed industries.
What is protein analysis used for?
Protein analysis may be used to support:
- Nutritional information panels
- Product specifications
- Customer requirements
- Export and market access requirements
- Quality assurance programmes
- Supplier verification
- Batch release testing
- Product development and reformulation
- Routine production monitoring
Protein content is an important quality and composition measure for many products, particularly where product value, nutritional claims, or customer specifications depend on accurate protein results.
Method principle
The Kjeldahl method determines protein by measuring nitrogen in the sample.
During analysis, the sample is digested using acid and catalyst under controlled conditions. This converts organic nitrogen in the sample into ammonium sulphate. The ammonia is then released, distilled, and measured.
The measured nitrogen content is converted to protein using an established conversion factor appropriate to the product type.
This approach is widely accepted because it is robust, well understood, and strongly aligned with internationally recognised standards for protein determination.
What sample types can be tested?
Kjeldahl protein analysis is available for a range of product types, including:
- Dairy products
- Milk powders and dairy ingredients
- Flour and cereal products
- Grains and grain-based ingredients
- Animal feed
- Food ingredients and related manufactured products
If your product is not listed above, please contact us before submitting samples so we can confirm whether the method is suitable for your sample type and intended purpose.
Why use Kjeldahl protein analysis?
Kjeldahl is one of the most widely recognised methods for protein determination.
It provides:
- Reliable and consistent protein results
- Strong alignment with international reference methods
- Broad acceptance across dairy, food, cereal, and animal feed applications
- A well-established performance history
- Support for product specifications, regulatory requirements, and customer assurance programmes
For many customers, Kjeldahl protein analysis provides a practical and dependable testing pathway for routine protein determination.
Standards and accreditation
AsureQuality performs Kjeldahl protein analysis using internationally recognised methods relevant to the sample matrix.
This includes recognised methods for dairy, flour and cereal, and animal feed matrices.
Accreditation status may vary depending on the sample type and method. If accreditation is required for your testing programme, please confirm this with our team before submitting samples.
Before submitting samples
Before submitting samples, please check the protein testing requirements in your product specification, customer agreement, regulatory requirement, or internal quality documentation.
Please include clear product and sample details with your submission so our team can apply the appropriate testing pathway.
Have a question, comment, or feedback?
If you have any concerns regarding general testing services, please submit a request to contact or customer experience team or call +64 9 626 8203