Sustainable methods in modern nutritional analysis

New: NMR method now available with DAkkS accreditation

The NMR method for the sustainable determination of protein content in food and feed has been successfully approved by DAkkS and has been offered with accreditation since February 2026.

Microwave-based fat determination in food and feed

The classical methods for fat determination (e.g. Röse-Gottlieb or Weibull-Stoldt) are gravimetric and are based on the hydrolysis of a sample with acid and the subsequent extraction of the fat with an organic solvent. This is time-consuming and involves a high consumption of chemicals and electricity.
In microwave-based fat determination, these chemical reaction steps are carried out in parallel in a closed vessel within a microwave (closed-vessel technology). This shortens the analysis time and reduces chemical consumption by 70%. Both methods are identical in terms of accuracy, sensitivity and robustness. However, the power consumption and space requirements of the microwave-based method are lower than those of the classical method.

Dumas for determining the protein content of food and feed

The Kjeldahl method has long been the most common method for determining the protein content of food, but in recent years the Dumas method has also gained in importance. It is based on the combustion of a sample and the subsequent determination of its total nitrogen content and offers a faster and safer alternative to the Kjeldahl method based on "green chemistry". This means that no aggressive acids, alkalis or SVHC (Substances of Very High Concern), which are on the candidate list for authorisation under the REACH regulation, are used in the Dumas analysis. The analysis per sample only takes about 5 minutes and not several hours, as it is the case with the Kjeldahl method.

Dumas as an internationally recognised method

The Dumas method has been recognised for more than 25 years and is now validated by a number of international organisations including AOAC, AACC, ISO, AOCS and OIV. There are ISO standards for numerous food that use this method for the determination of proteins. In addition, Commission Regulation (EC) No 152/2009 states that the Dumas method may be used for the analysis of crude protein in feed, provided that it produces results comparable to those obtained using the Kjeldahl method.

In addition, the European Commission expressly permits the use of the Dumas method instead of the Kjeldahl method for the routine analysis of foodstuffs, provided that it has been validated against the Kjeldahl method and delivers comparable results, as is the case with animal feed. Consequently, the protein content declared for all food and feed is determined by multiplying the Dumas nitrogen by 6.25 (6.38 for dairy products). Our determination of protein content by the Dumas method complies with the labelling requirements set out in the European Labelling Regulation (EU) No. 1169/2011.

The Dumas method for the sustainable determination of protein content in food and feed has been successfully approved by DAkkS and has been offered with accreditation since August 2025.

NMR for determining the fat content of food

The use of nuclear magnetic resonance (NMR) spectroscopy to determine the   fat content in food is based on the quantitative analysis of protons in the lipid fraction. The method is      characterised by high precision and reproducibility, as it is based on physical principles and is not influenced by    chemical reactions or matrix effects.

In contrast to the classic chemical-gravimetric method, NMR does not require time-consuming sample preparation and does not involve the use of acids or solvents. In addition, the measurement itself takes only a few minutes. It is therefore ideal for the reliable and rapid determination of the fat content in food. 

NMR as an internationally recognised method

For milk and milk products, an ISO/IDF standard for the application of NMR technology as a reference method for fat determination in milk and milk products was published in 2024.

Since the method is relatively new compared to the classic wet chemical method and the purchase of an NMR involves considerable costs, not many standardised methods have been published yet.

According to the European Labelling Regulation (EU) No. 1169/2011, the fat content to be declared includes all lipids, including phospholipids. The regulation does not specify a method to be used. The NMR method used by Eurofins to determine the fat content in foodstuffs detects both fatty acids and phospholipids. Consequently, the method complies with the requirements of the European Labelling Regulation for indicating the fat content in foodstuffs.

The NMR method is the preferred method for routine analyses. It is faster, safer and, compared to the classic Weibull-Stoldt reference method, is based on 'green chemistry'.

NIR for parallel fat, water, protein and BEFFE determination

NIR spectroscopy (near infrared spectroscopy) enables the combined determination of water, fat, protein and BEFFE content in a single analysis method. The sample is irradiated with light, the absorption spectrum is measured and the spectra are used to quantitatively determine the contents using a database. In contrast to the classic wet-chemical methods for water (drying oven), fat (Weibull-Stoldt), protein (Kjeldahl) and BEFFE (photometric determination), the analysis time of NIR spectroscopy is only a few minutes for all 4 parameters. In addition, it requires no chemicals, produces no waste and is non-destructive, so the sample material can be used for further analysis after NIR spectroscopy. We already offer accredited NIR spectroscopy for routine analysis of meat and cheese products. We are happy to extend the method for you by purchasing additional databases for other matrices such as baked goods, beverages, cereals and dairy products.