Whey protein is a collection of proteins found in whey, a byproduct of cheesemaking. When a coagulant (usually rennet) is added to milk, the curds (casein) and whey separate; whey protein is the water-soluble part of milk. Whey protein is often consumed as a supplement in the form of dry powders with various levels of processing that affect how concentrated a source of protein they are and how fast they’re absorbed. There are three main types of whey protein: whey concentrate, whey isolate, and whey hydrolysate.
What is whey protein?
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•Last Updated: May 16, 2025
Whey protein is a collection of proteins derived from whey, which is a byproduct of cheesemaking and is the water-soluble part of milk. It is commonly consumed as a supplement in dry powder form, with 3 main types (whey concentrate, whey isolate, and whey hydrolysate) that vary in protein concentration and absorption rates.