The purpose of the present invention is to provide a simple means that makes it possible to inhibit degradation in the freshness of myoglobin-containing food. The present invention pertains to a material for inhibiting degradation in the freshness of myoglobin-containing food, the material including a substrate that contains a polymeric compound, an antioxidant covering at least a part of the surface of the substrate, and/or an antioxidant supported on a layer that forms at least a part of the surface of the substrate, the antioxidant being contained at 0.01g/m