Abstract: Provided is a composition comprising a non-ionic surfactant, an anionic surfactant, a carboxylic acid, a volatile oil, an amine, a nitrogen source, and water. This composition is useful in treating composting material used for cultivating edible fungi such as mushrooms to significantly reduce the malodorous gases normally associated therewith. Mushrooms and other edible fungi grown on such treated compost material exhibit enhanced nutritional qualities, including lower sodium levels and increased protein levels compared to fungi grown on conventionally prepared compost.