Substances deployed specifically to suppress mould and yeast growth in or on foods. The approved arsenal includes sorbic and propionic acids for bakery products, natamycin for cheese surfaces and fermented sausages, and sulphur dioxide in wines and dried fruit — each with defined uses and maximum levels. Choice depends on the target organisms, the food’s pH and water activity, and what regulations permit in each market. Labels must declare them, and manufacturers must demonstrate efficacy under real storage conditions. Over-reliance on any single agent invites resistant spoilage strains, so hurdle strategies combine them with other controls.