Fuente: WIPO "milk" A method for producing whey according to one aspect of the present invention includes a step of heating raw material milk containing casein and whey protein under a heating condition of an Fo value of 1.0 × 10-9 or more, a step of cooling the raw material milk heated under the heating condition to a temperature T1 of less than 20°C, and a step of subjecting the raw material milk cooled to the temperature T1 to microfiltration membrane treatment to obtain whey as a membrane permeation fraction.