A beverage barrel with a tap attachment arranged thereon, wherein the tap attachment has: - a basic body with at least one fastening element for fastening the tap attachment on the beverage barrel, - a connecting device for a gas source, - a first valve assembly with a pressure controller and a gas channel (5") with an orifice pointing into the interior of the beverage barrel, wherein the first valve assembly opens or closes the gas channel (5") between the connecting device and the orifice, - a first actuating device for actuating the first valve assembly, - a second valve assembly and an ascension pipe with an orifice pointing into the interior of the beverage barrel, and a tap with an outlet, the tap being connected to the ascension pipe via the second valve assembly, and - a second actuating device for actuating the second valve assembly, - a gas-proof expansion device surrounding the gas channel (5") at the latter's orifice, the gas-proof expansion device being transferable from a non-expanded state into an expanded state by gas being supplied from the gas source and the gas-proof expansion device being configured such that, in the expanded state, it has a volume which corresponds at least to an interior volume of the beverage barrel, and - a rod as a stabilisation device for the expansion device, the rod being present at the expansion device and being surrounded by the same and stabilising it when it is transferred from the non-expanded state into the expanded state, and the rod being configured as a gas feeding pipe with an interior channel which continues the gas channel (5"), wherein the gas feeding pipe extends away from the basic body such that it protrudes into the interior of the beverage barrel, and wherein the beverage barrel has at least one spacer element which extends from the bottom of the beverage barrel towards the cover at least on the inner lateral area of the beverage barrel and which is configured to form a fluid channel when the expansion device of the tap attachment is in the expanded state. - a basic body with at least one fastening element for fastening the tap attachment on the beverage barrel, - a connecting device for a gas source, - a first valve assembly with a pressure controller and a gas channel (5") with an orifice pointing into the interior of the beverage barrel, wherein the first valve assembly opens or closes the gas channel (5") between the connecting device and the orifice, - a first actuating device for actuating the first valve assembly, - a second valve assembly and an ascension pipe with an orifice pointing into the interior of the beverage barrel, and a tap with an outlet, the tap being connected to the ascension pipe via the second valve assembly, and - a second actuating device for actuating the second valve assembly, - a gas-proof expansion device surrounding the gas channel (5") at the latter's orifice, the gas-proof expansion device being transferable from a non-expanded state into an expanded state by gas being supplied from the gas source and the gas-proof expansion device being configured such that, in the expanded state, it has a volume which corresponds at least to an interior volume of the beverage barrel, and - a rod as a stabilisation device for the expansion device, the rod being present at the expansion device and being surrounded by the same and stabilising it when it is transferred from the non-expanded state into the expanded state, and the rod being configured as a gas feeding pipe with an interior channel which continues the gas channel (5"), wherein the gas feeding pipe extends away from the basic body such that it protrudes into the interior of the beverage barrel, and wherein the beverage barrel has at least one spacer element which extends from the bottom of the beverage barrel towards the cover at least on the inner lateral area of the beverage barrel and which is configured to form a fluid channel when the expansion device of the tap attachment is in the expanded state.