Digestibility assay: PDCAAS / DIAAS + digestibility kinetics

Evaluating protein digestibility is an essential step in determining its nutritional value and effectiveness in food and nutraceutical formulations. The Protein Digestibility Corrected Amino Acid Score ( PDCAAS DIAAS ) indices are the two main recognized methods for measuring protein quality.

These analyses provide a precise view of the actual intake of essential amino acids and the bioavailability of proteins. They apply to both human and animal nutrition and respond to regulatory, scientific and commercial issues.

Understanding the PDCAAS and DIAAS indices

• PDCAAS (Protein Digestibility Corrected Amino Acid Score) : A long-standing standard method, it combines a protein's amino acid profile with its overall digestibility. Its score is limited to 100%, which can mask some differences between protein sources.
• DIAAS (Digestible Indispensable Amino Acid Score) : a more recent method now recommended by the FAO, it measures the digestibility of each essential amino acid individually, providing a more detailed and representative assessment of protein quality.

These scores are used by manufacturers to compare different protein sources (animal, vegetable or mixed proteins) and to support their nutritional claims.

Digestibility kinetics

In addition to the indices, the study of digestibility kinetics makes it possible to evaluate the speed of protein degradation and absorption. It provides information on the progressive release of amino acids, distinguishing, for example, between fast-digesting proteins (whey) and slow-digesting proteins (casein).

This approach is particularly useful in:

• The formulation of food supplements for athletes
• Optimization of products enriched with vegetable proteins
• Research on satiety and nutritional efficiency
• Animal nutrition, to adjust rations according to actual bioavailability

Analytical methods used

The methods applied to the dosage of digestibility are based on standardized protocols:

• In vitro methods : simulated digestion protocols such as INFOGEST, combining enzymes and physiological conditions to reproduce gastrointestinal digestion.
• In vivo methods : carried out on animal or human models to validate experimental results and calculate the PDCAAS and DIAAS indices.
• Spectrophotometry : used to measure the concentration of released amino acids and monitor digestion kinetics.

These methods guarantee a reliable, reproducible assessment aligned with international recommendations.

Sectors concerned by digestibility analysis

Protein digestibility testing is particularly relevant in:

• Human nutrition : development of protein-enriched products (drinks, powders, protein bars).
• Nutraceuticals : formulation of protein food supplements and optimization of nutritional profiles.
• Animal nutrition : evaluation of plant or animal protein sources to improve feed efficiency and reduce costs.
• Plants and raw materials : characterization of new sources of plant proteins (peas, soy, hemp, rice, insects).

Typically analyzed matrices

The matrices subjected to these analyses include:

• Protein supplements (powders, capsules, drinks)
• Protein-enriched food products (snacks, bars, meal replacements)
• Animal feed and nutritional premixes
• Plant or animal raw materials intended for processing
• Innovative protein extracts from new sources (microalgae, insects, legumes)

Scientific, regulatory and industrial issues

The analysis of protein digestibility responds to strategic issues:

• Regulatory compliance : substantiating nutrition and health claims.
• Product differentiation : promoting the protein quality of a formulation compared to competitors.
• Nutritional optimization : adjust amino acid profiles for better bioavailability.
• Economic efficiency : improving protein conversion in animal nutrition.

YesWeLab support for your digestibility analyses

YesWeLab collaborates with a network of partner laboratories specializing in human and animal nutrition. Our partners, accredited and certified (ISO 17025, COFRAC), use validated protocols to guarantee reliable and recognized results.

Thanks to our digital platform, you benefit from:

• Simplified submission of your samples
• Real-time monitoring of your analyses
• Fast results that meet international standards

Our scientific team will help you choose the method (in vitro or in vivo) best suited to your needs, depending on your matrices and your objectives.

Related analyses

• Dosage of essential amino acids
• Analysis of total nitrogen content (Kjeldahl method)