Natamycin is used to externally protect food matured by microorganisms, like certain cheeses and dried meats. It prevents the external formation of moss without affecting the bacterial flora which favours its maturing.
In Europe, natamycin is often used in the surface treatment of dry fermented sausages and also to treat the surface of cooked hams.
Regulation (EU) 438/2013 of the European Commission, 13 May 2013, modifies and corrects annex II of Regulation (EC) 1333/2008 of the European Parliament and Council with regard to the use of certain food additives. In this Regulation, Natamycin (E 235) is authorised, amongst other additives, in the surface treatment of cold slice and for different food products.
The European regulation for meat is similar to that for cheese. The maximum level of natamycin on the surface of dry cured sausages is 1 mg/dm2, and it must be absent at a depth of more than 5 mm.