What does isolated mean? Simply that once the protein is manufactured using water to remove most of the sugar in regular whole whey, the protein is then precipitated and dried. Usually an isolate i 90% pure and supposedly superior to a concentrate. My whey protein concentrate has a purity of 80%. While still not bad, isolate is still better.
Now, casein is really just cottage cheese with a higher amount of the milk sugar lactose and the mineral calcium. It is used for other things other than for bodybuilding. As starters, it is made from precipitated milk, which can then be reconverted into glutinous casein glue with the aid of alkali. Casein is one of the first binders ever used by mankind. Casein can be painted on a variety of surfaces, including wood and plaster. Which ever surface used, it must be a rigid one as casein is to brittle to paint on a flexible surface (such as canvas). Casein is also an emulsifier this allows you to "combine" oil and water.
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