A liquid metering assembly is described and which includes a container for enclosing a source of a liquid to be dispensed a container cap defining a dispensing aperture and a vent aperture which is releasably affixed to the container a moveable diaphragm releasably cooperating with the container cap, and coupled in fluid flowing relation relative to the dispensing aperture, and wherein the moveable diaphragm has a valve member and a moveable liquid volume control member which cooperates with the moveable diaphragm, and wherein, when a predetermined suction is applied to the dispensing aperture of the container cap, a user may withdraw a given volume of liquid from the beverage container.