Abstract: The invention pertains to a process for simultaneous producing an infant formula product and a dairy product from defatted animal milk, comprising (a) processing the milk into a casein stream, a whey protein stream and a lactose stream by a combination of microfiltration and ultrafiltration, wherein the casein stream originates from the microfiltration as retentate, the whey protein stream originates from the ultrafiltration as retentate and the lactose stream originates from the ultrafiltration as permeate; (b) combining at least part of the whey protein stream originating from step (a) and a lactose source to obtain are combined stream; (c) using the recombined stream originating from step (b) in the manufacture of the infant formula product; and (d) using at least part of the casein stream originating from step (a) and defatted animal milk in the manufacture of the dairy product.