A food preservative is a substance added to food to prevent spoilage caused by bacteria, fungi, or other microorganisms, as well as to slow down oxidation and rancidity. Preservatives help extend the shelf life of food products, maintaining their quality and safety for a longer period. Common food preservatives include sodium propionate, calcium propionate, potassium sorbate, natamycin, sodium benzoate, and nisin. They are used in a wide range of food products, including canned goods, cured meats, snacks, and baked goods. The use of food preservatives is regulated to ensure that they are safe for consumption and do not pose health risks.