Mould growth may be produced in cheese, rendering it unfit for human consumption. Therefore, during ripening, cheeses are protected against development of mould by coating of their surfaces a protective layer.
Natalac™, containing 50% natamycin produced by fermentation using a strain of “Streptomyces natalensis”, has considerably facilitated protection of cheeses against mould growth during ripening. "Natalac™" may either be added to brine, used as an aqueous suspension for dipping of cheeses or added to polyvinyl acetate used to coat the cheese.
*Natamycin, at a concentration considerably lower than other known fungicides, destroys both mould hyphae and spores. The inhibitory concentration of sorbate is as high as 300 mg/dm² of cheese surface, while the permissible concentration of natamycin is only 2 mg/dm². Sorbate diffuses into cheese and affects its organoleptic properties, whereas the migration of natamycin is negligent, and when used in polyvinyl acetate, it remains on a surface of the cheese.