ABSTRACT
On a dry-matter basis, the protein content of whey is comparable to that in barley, oats, and wheat. Whey protein is one of the highest quality, naturally occurring proteins having a protein efficiency ratio of 3.0 to 3.2 compared to casein at 2.5. The compositions of acid and sweet wheys are generally considered to be identical; however, some differences may occur. Acid whey usually contains more calcium and phosphorus than sweet whey since a large part of the calcium phosphate is liberated upon acidification. Feeding large amounts of dried whey in grain rations may present some feed handling problems worth considering. Whey proteins are some of the highest quality natural proteins available which makes them an excellent protein source for nonruminants. The production of whey protein concentrates also leaves the deproteinized whey to be disposed of or utilized in some manner. The deproteinized whey contains mostly lactose and ash. Lactose is fermented to lactate by many microorganisms commonly found in the rumen.
