Abstract: For use with frozen food products, such as dough, having a substantially larger bulk volume at an elevated temperature than when frozen, a container is erected from a container blank having a plurality of fold lines and being so arranged that, when the blank is folded along a first selection of said fold lines in a first manner, it defines a container having a bulk capacity of a first predetermined volume and, when folded along a second selection of said fold lines in a second manner, it defines an open, tray-like container having a bulk capacity of a second predetermined volume larger than the said first volume, and a base area different from the base area when the blank is folded in said first manner. The ratio of the said volumes is preferably 1:2. The blank may be glazed or lined (e.g. with aluminum foil) on at least one side thereof.