If a whey protein concentrate (WPC) is described as hydrolyzed, it has been treated with enzymes to break down either the protein or the lactose into smaller components.

Hydrolyzed WPC is useful in infant formulas and other special dietary applications to speed digestion and lower allergenic potential.

If a WPC is protein-hydrolyzed, it delivers more peptides and free amino acids. WPC can also be lactose-hydrolyzed. This means that the lactose has been broken down into simple sugars, making it easier to digest for those who may be lactose-intolerant.