Yeast and mold growth may be produced in cheese, rendering it unfit for human consumption. Therefore, during ripening, cheeses are protected against development of mold by coating of their surfaces a protective layer.
Mould growth on the surface of sausages is generally undesired. Unsuitable storage conditions, such as high humidity and temperature, can affect the surface stability of the sausages and moulds spores can germinate and grow on them. To increase the production security and prevent the growth of moulds, the sausage surface is often treated with natamycin with rosemary extract.
Natanacl™, containing min. 50% natamycin produced by fermentation using a strain of “Streptomyces natalensis”, has considerably facilitated protection of cheeses against yeast and 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 mold 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.