A temperature-retaining device includes an upper wall and a lower wall. The upper wall includes a conduction plate having a top surface and a bottom surface comprising a plurality of downwardly projecting fingers. A temperature-retaining body is disposed in contact with the plurality of fingers to transfer heat from the temperature-retaining body to the conduction plate. A support structure is coupled to the upper wall and has a peripheral wall surrounding the temperature-retaining body. A lower wall is coupled to the support structure to enclose the temperature-retaining body within a cavity defined by the upper wall, support structure and lower wall. The lower wall comprises a gas-permeable channel that is substantially impermeable to liquids.