To extrude draft beer without bringing any extrusion gas into direct contact with draft beer by providing a diaphragm having at least one nature of expandability and flexibility between draft beer in a draft beer barrel and extrusion gas.
A connection part 5 of a connection port 3 of a draft beer take-out passage 2 to an extrusion gas supply passage 4 is formed on an upper part of a barrel 1 to store draft beer. A pipe 6 is lead from the connection port 3 into the barrel 1, and a bag-like diaphragm 7 is fitted thereto. The diaphragm 7 is formed of a material such as rubber including, for example, a synthetic resin film which is excellent in gas barrier property and expandable and flexible. The extrusion gas supply passage 4 is connected to a gas cylinder to store the extrusion gas such as nitrogen gas, and the extrusion gas is supplied between an outer surface of the diaphragm 7 and an inner surface of the barrel. Draft beer stored in the diaphragm 7 is fed into the draft beer take-out passage 2 by pressurizing the diaphragm 7 with the extrusion gas from the outside.
TAKAHASHI ATSUSHI
KAWABE MITSUNORI
