A whey protein isolate (often whey isolate) is a dietary supplement and food ingredient created by separating components from whey. Whey is milk by-product of the cheese-making process. Whey can be processed to yield whey protein in three forms: whey isolate, whey concentrate, or whey hydrolysate. The difference between the whey protein forms is the composition of the product, particularly the protein content. Whey isolates contain the higher percentage of pure protein and can be pure enough to be virtually lactose free, carbohydrate free, fat free, and cholesterol free.[citation needed] Whey proteins are highly bioavailable, are very quickly absorbed into the body, and have a high concentration of branched-chain amino acids (BCAAs)[medical citation needed] which are highly concentrated in muscle tissue, and are used to fuel working muscles and stimulate protein synthesis. What's the Difference Between Whey Isolate and Whey Concentrate? There are several nutritional differences between whey isolate and concentrate. These differences are caused by the processing methods. When the liquid whey is collected as a by-product of cheese or yogurt production, it undergoes several processing steps to increase its protein content. After a sufficient protein concentration is achieved, the liquid can be dried to form whey concentrate powder that consists of up to 80% protein by weight. The remaining 20% of the whey concentrate powder contains carbohydrates and fats. If different processing steps are used to reduce the fat and carbohydrate content of whey, a whey isolate powder containing 90% or more protein by weight can be produced. Overall, the processing steps used in the production of whey isolate result in higher protein content and lower fat and carbohydrate content per serving. However, the types of amino acids found in both forms of whey are virtually identical, since they are derived from the same proteins. In addition to having lower total carbohydrate content, whey isolate also has lower lactose content. This means that it could be a better choice for those who are lactose intolerant. Nevertheless, the amount of lactose in both forms of whey protein is likely to be low enough for those who are lactose intolerant to use. In addition to their nutritional differences, there are cost differences between these two types of whey. Generally, whey isolate is more expensive than whey concentrate. While this makes sense based on the higher purity of whey isolate, taking a larger quantity of whey concentrate can bring you the same dose of protein, often at a lower cost.