Natamycin is applied as a preservative agent on the surface outside, and taking current legislation into account (COMMISSION REGULATION (EU) No. 1129/2011 of 11 November 2011 amending Annex II to Regulation (EC) No 1333/2008 of the European Parliament and of the Council by establishing a Union list of food additives)
There, the Natamycin acts as an inhibitor preventing contamination of the cheese, as it does not invade the product, it also does not jeopardise the end product, because it does not alter the main fermentation process. It also does not change the characteristics of the cheese to be marketed, in terms of its colour, aroma and texture.
Food additives such as Natamycin are applied to the rind of cheese to achieve the desired effect, either scattered in water and applied using a spray, or by immersing the cheese in the solution.