Fuente: WIPO "milk" 247,617. White, A. E., (Milk Oil Corporation). Nov. 30, 1923. Butter.-Milk or cream is repeatedly washed and the milk fat or oil separated from the skim milk and other liquid by centrifugal separations to remove the casein the other remaining solids other than fat and the water. The small amount of casein that remains with the fat is then coagulated by the addition of rennet. The milk fat or oil separates out and is separated by passing through a whey separator preferably with the addition of about four parts of water. The fat or oil may then be further dried by means of an oil separator.