Propellants help expel the food from its container. Propellants are sealed under pressure in an aerosol food container. They enable an aerosol can to spray out its contents, like cream in a can with a nozzle. Propellants should always be listed on the label by name rather than using the class name propellant followed by the code number. Common propellants used are Carbon dioxide, Nitrogen, Nitrous oxide, Butane, Isobutane, Propane, Octafluorocyclobutane