The Foundation of Protein Claims: Quantity and Quality
For food products to carry a "good source of protein" or "high in protein" claim, they must meet specific regulatory criteria that go beyond simply stating the total grams. The US Food and Drug Administration (FDA) and other regulatory bodies emphasize the importance of both protein quantity and quality. The primary tool for assessing protein quality is the Protein Digestibility-Corrected Amino Acid Score (PDCAAS), which measures how well a protein can be digested and absorbed by the human body.
What is PDCAAS and How is it Calculated?
The PDCAAS method compares a food's essential amino acid profile to a standard reference pattern for human needs, typically that of a 2- to 5-year-old child. The amino acid score is then corrected for protein digestibility, which is often determined through lab testing. The PDCAAS is a score from 0 to 1.0, with 1.0 being the highest possible score. This score is then used to calculate the 'quality-corrected' grams of protein per serving, which is the basis for US-based protein claims.
Steps for a US Protein Claim Calculation
- Determine the grams of protein per serving. This value is found on the Nutrition Facts label.
- Determine the product's PDCAAS value. This typically requires laboratory analysis, although published values for common ingredients can sometimes be used.
- Calculate the quality-corrected grams. Multiply the grams of protein per serving by the PDCAAS value.
- Reference the Daily Value (DV). The DV for protein is 50 grams for adults and children 4 years or older.
- Calculate the %DV. Divide the quality-corrected grams by 50 and multiply by 100 to get the percentage.
Protein Claims Across Different Markets
Protein claim regulations vary by region, with different thresholds and calculation methods. Food manufacturers must ensure their products comply with the specific rules of their target market.
| Claim Type | US FDA Regulations | European Union (EU) Regulations | Australia & New Zealand (ANZ) Regulations |
|---|---|---|---|
| "Good Source of Protein" | At least 10% of the DV (5g) of quality-corrected protein per serving. | At least 12% of the food's energy value (calories) must come from protein. | At least 10g of protein per serving. |
| "High in Protein" or "Excellent Source" | At least 20% of the DV (10g) of quality-corrected protein per serving. | At least 20% of the food's energy value (calories) must come from protein. | At least 2x the level for a "good source" claim, or 20g per serving. |
The Importance of Correct Labeling
Accurate protein claims are crucial for consumer trust and brand reputation. An improperly calculated claim can be misleading and lead to regulatory action. For example, a product using a low-quality protein like wheat gluten (PDCAAS ≈ 0.25) might have a high raw protein count, but its quality-corrected amount would be significantly lower. Without proper calculation and the %DV, the label overstates the usable protein for consumers. This practice is why the FDA requires the %DV to be listed when a protein claim is made, ensuring a more honest representation of the nutritional value. Regulatory frameworks like PDCAAS provide a standardized, scientific approach to prevent such misrepresentations.
Conclusion
To successfully calculate a source of protein claim, manufacturers must move beyond simple raw gram counts and consider protein quality and digestibility. Using standardized metrics like PDCAAS, in compliance with regional regulations such as those from the FDA or EU, ensures that nutritional claims are accurate, scientifically sound, and truthful to the consumer. This not only maintains regulatory compliance but also builds consumer trust in the product's nutritional value. Adhering to these guidelines is a fundamental step in responsible food labeling. For further detail on regulatory methodology, the FDA's regulations under 21CFR101.9 provide comprehensive guidance on nutrition labeling and the use of PDCAAS.
