What is PDCAAS and how does it differ from PER?
Protein digestibility-corrected amino acid score (PDCAAS) is a relatively new, and potentially more accurate method for evaluating the quality of food proteins. PDCAAS is based on a food protein’s amino acid content, its digestibility, and its ability to supply essential amino acids in amounts adequate to meet the needs of humans. PDCAAS has replaced the Protein Efficiency Ratio (PER), which had been the accepted method for evaluating protein quality since 1919. Since PER measures the ability of protein to support growth in young, growing rats, it overestimated the need for certain amino acids. This led to a general overestimation of the quality of animal protein and an underestimation of the quality of plant proteins. Adoption of the PDCAAS method as the standard allows evaluation of food protein quality based on the needs of humans. PDCAAS is currently the method recognized by the Food and Drug Administration (FDA) and other international organizations for food labeling.
