Abstract: Continuous production of milk with a predetermined fat content wherein whole milk is divided into a cream fraction and a skim milk fraction in a centrifugal separator. A part of the cream fraction is remixed into the skim milk fraction in order to obtain a mixed fraction of milk with desired fat content. The whole flow of cream fraction which has been obtained from an outlet from the centrifugal separator is remixed with a flow of skim milk fraction from a second outlet from the centrifugal separator by way of a valve in the outlet for cream fraction during a certain period. During a second intermediate period the whole flow of cream fraction is discharged by the valve for separate collection. The periods mentioned above are so short that the fat content and the flow per time unit of the mixed fraction may be regarded as homogenous.