An object of the present invention is to provide a simple measure which can suppress freshness deterioration of a myoglobin-containing food. The present invention relates to a myoglobin-containing food freshness deterioration suppressing material for suppressing freshness deterioration of a myoglobin-containing food, comprising: a substrate comprising a polymer； and an antioxidant with which at least a part of the surface of the substrate is covered, and/or an antioxidant supported in a layer forming at least a part of the surface of the substrate； wherein 0.01 g/m 2 or more and 20 g/m 2 or less of the antioxidant is included relative to the area of the part in which the antioxidant is present, of the surface of the substrate.本發明的目的在於提供一種可抑制包含肌紅蛋白的食品的新鮮度惡化的簡便方法。本發明是有關於一種包含肌紅蛋白的食品新鮮度惡化抑制材料，其是用於抑制包含肌紅蛋白的食品的新鮮度惡化，包含含有高分子化合物的基材、以及將所述基材的表面的至少一部分被覆的抗氧化劑及/或承載於形成所述基材的表面的至少一部分的層中的抗氧化劑，且相對於所述基材的表面中存在所述抗氧化劑的部分的面積，含有0.01g/m2以上、20g/m2以下的所述抗氧化劑。
