Digestibility assessment: PDCAAS / DIAAS + digestibility kinetics

Assessing protein digestibility is a crucial step in determining its nutritional value and effectiveness in food and nutraceutical formulations. The PDCAAS (Protein Digestibility Corrected Amino Acid Score) and DIAAS (Digestible Indispensable Amino Acid Score) 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 are applicable to both human and animal nutrition and address regulatory, scientific, and commercial challenges.

Understanding the PDCAAS and DIAAS indices

• PDCAAS (Protein Digestibility Corrected Amino Acid Score) : a long-established 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 and now recommended by the FAO, it measures the digestibility of each indispensable amino acid individually, offering a finer and more representative assessment of protein quality.

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

digestibility kinetics

digestibility kinetics studies allow us to assess the rate of protein breakdown and absorption. They provide information on the progressive release of amino acids, distinguishing, for example, between rapidly digestible proteins (whey) and slow-digesting proteins (casein).

This approach is particularly useful in:

• The formulation of nutritional supplements for athletes
• Optimizing plant-based protein-enriched products
• Research on satiety and nutritional efficiency
• Animal nutrition, to adjust rations according to actual bioavailability

Analytical methods used

The methods applied to digestibility testing 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 : performed on animal or human models to validate experimental results and calculate 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 that is 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 challenges

Protein digestibility analysis addresses strategic issues:

• Regulatory compliance : justifying nutritional and health claims.
• Product differentiation : highlighting the protein quality of a formulation in the face of competitors.
• Nutritional optimization : adjusting 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 accredited and certified partners (ISO 17025, COFRAC) use validated protocols to guarantee reliable and recognized results.

Thanks to our digital platform, you benefit from:

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

Our scientific team will assist you in choosing the method (in vitro or in vivo) best suited to your needs, according to your matrices and objectives.

Related analyses

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