a portable , electrically powered keg tapping device for beer kegs has a valve body including a liquid passageway open to the bottom of the valve body and to a liquid dispensing port on the body and an air passageway open at the bottom of the valve body laterally spaced from the liquid passageway and coupled to the output of an ac or dc powered air pump which is controlled by a pressure regulator . in an alternative embodiment , a pumping assembly is provided with an adapter plate which can be used to convert a manually operated keg tapping apparatus to a powered , pressure - regulated tapping apparatus .