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PDCAAS
The Protein Digestibility-Corrected Amino Acid Score rates protein quality from 0 to 1 by combining the amino-acid profile with digestibility. Whey, casein, egg, and soy score at or near the 1.0 ceiling; most single plant proteins land lower, which is the technical case for blends. It is the standard most labels lean on when they claim "high-quality protein." We reference it factually to explain why sources differ — it is a measurement, not a marketing grade, and it says nothing about any health outcome.
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