Together with European partners, Agroscope researchers have developed a method for determining protein digestibility in vitro. The method quantifies the amino acids in foods released by digestion and allows for the evaluation of protein quality without animal testing.
In vitro protocol published in prestigious Nature Protocols Journal
Together with European partner institutions, Agroscope has developed an expanded in vitro method for determining protein digestibility. The protocol was published under the name ‘INFOGEST Quant’ in the scientific journal Nature Protocols, one of the world’s most prestigious journals on scientific methods. INFOGEST Quant builds on the internationally established INFOGEST 2.0 Digestibility Model co-developed by Agroscope, supplementing it with analytics modules that enable calculation of the digestibility of essential amino acids and the so-called DIAAS (Digestible Indispensable Amino Acid Score). The method was validated with data from in vivo studies and shows a high degree of alignment, underscoring its suitability for research and quality assessments.
Alternative to invasive animal testing
The nutritional quality of proteins depends both on their amino acid composition and their digestibility. Dietary proteins must provide sufficient levels of essential amino acids (EAAs) to meet EAA requirements. The Digestible Indispensable Amino Acid Score (DIAAS) is the FAO-recommended international standard for evaluating protein quality, but typically requires invasive animal or human testing. With INFOGEST Quant, research, industry and public authorities benefit from a standardised in vitro method allowing for efficient, ethically defensible screenings as well as high reproducibility and cost-efficiency. In this way, we enable the Swiss agricultural sector and food producers to highlight the protein quality of their products in addition to their taste and flavour.
Step-by-step protocols enable wide application
The protocol can be implemented with standard laboratory equipment and without specialised infrastructure. Preparation takes around six days, the complete process around eight days. Depending on the method, residue analysis requires another three to five days.
Protein quality as part of the ecological footprint
The method also enables a differentiated ecological assessment of protein sources. Animal proteins, for example, often exhibit higher digestibility, which can directly affect ecological footprint calculations. With INFOGEST Quant this aspect can now be more easily taken into account for Swiss foods as well. The method is currently being further developed into an international standard with the participation of the International Dairy Federation (IDF) and the International Organization for Standardization (ISO), and in the future will therefore also be recognised for the quality assessment of foods in international trade contexts.
Conclusions
- Together with European partners, Agroscope has developed an expanded in vitro protocol for determining protein digestibility and DIAAS which was published in Nature Protocols.
- The method replaces invasive, ethically complex animal testing and enables the protein quality of foods to be determined in a more cost-effective manner.
- The protocol is suitable for routine use, requires only standard laboratory equipment, and has been successfully validated with in vivo data.
- The method can be applied in research and product development as well as in quality control.
- This enables the Swiss agricultural sector and food producers to highlight the protein quality of their products in addition to their taste and flavour.
