Which of the following is the highest quality source of protein based on PDCAAS?

The highest quality source of protein based on the Protein Digestibility-Corrected Amino Acid Score (PDCAAS) is casein. PDCAAS is a method of evaluating the quality of protein by taking into account both the amino acid requirements of humans and the digestibility of the protein.

Casein, which is a protein found in milk, has a PDCAAS score of 1.0, indicating that it contains all essential amino acids in the quantities needed for human health and is highly digestible. This makes it an excellent protein source, especially for muscle repair and growth, as well as overall nutrition.

In comparison, while beef and chicken are also high-quality protein sources, they typically have slightly lower PDCAAS scores than casein due to different amino acid profiles and digestibility rates. Beans, although nutritious, are considered lower in protein quality compared to animal sources because they lack certain essential amino acids and have lower digestibility. This highlights the importance of evaluating protein sources on the basis of the PDCAAS for determining their effectiveness in meeting dietary protein needs.