Protein in milk comprises two groups: casein that we cheese makers want and whey proteins.  Whey protein is more water soluble and does not form large structures like the micelle chains of casein. Preserve Your Yield All cheese makers know that the higher the level of protein (casein) in milk, the higher the yield of curd, so we want to be gentle with our milk and not damage the casein element of the protein. Excessive heat Heat damages casein.  The optimum level for pasteuri