An apparatus for supporting liquid-filled containers having removable closures contacting an interface at one end, in a manner to attenuate escape of gas from the containers between the closures and the interface has a supporting framework and at least one insert within the framework, the insert engaging the framework and presenting a surface having a plurality of indentions in the shape of the liquid-filled containers, each indention conforming to shape of one of the containers in a manner that a container placed in the indention is supported with an axis of symmetry of the container at an acute angle with horizontal and with closure end down, such that liquid in the container surrounds the closure and interface, so gas will not escape between the closure and the interface.