Pressurized brewing, gas infusion and dispensing machine

A pressurized beverage dispenser having a beverage container and a cap. The cap includes a cap body, a compressed-gas cartridge, an external straw, a discharge chamber, a metering valve, a diaphragm, and an actuator. The discharge chamber within the cap body is in fluid communication with an internal passageway of the external straw. The metering valve allows a flow of beverage from the beverage container to the discharge chamber when the metering valve is open and substantially precludes the flow of beverage when the metering valve is closed. The diaphragm opens the metering valve when the diaphragm is activated and closes the metering valve when the diaphragm is deactivated. The diaphragm also activates when a user sucks on the outlet end of the external straw to create suction within the discharge chamber. The actuator on the cap body activates the diaphragm when the user manually engages the actuator.