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PDCAAS stands for protein digestibility-corrected amino acid score. This score rates the protein based on bioavailability and essential amino acid supply. The highest score is 1.00. Eggs have a score of 1.00. Protein powders are generally not made entirely of protein. Because of this, it is important to look at how much protein you are getting, and how many other ingredients there are. Concentrate contains between 30% and 85% protein. It is cheaper and easier to find. Isolate contains more than 90% protein and is more expensive. When purchasing protein powder, be sure to check the label for the percentage of protein to be sure you are getting the best powder for your money. You will want to know how much of each protein is in the blend before you purchase the powder. This should be stated somewhere on the label. If the amount of each protein is not stated, you may want to consider another blend. Proteins are made up of amino acids and, in order to be a complete protein, they must contain all 9 essential amino acids. Amino acid powders have their functions, but will not do the same thing as a protein powder.
Understand what PDCAAS rating stands for. Know the difference between isolate and concentrate. Check the label when purchasing protein blends. Know that amino acid powders are not the same as protein powders.