The biotechnologically obtained natamycin is used as a preservative and also as a medicine. It has an antimycotic (antifungal) effect on human skin and mucous membranes, but also on sausage and cheese. It is used as a broad spectrum mycotic against athlete’s foot and vaginal thrush, among other things. If you put it on the surface of sausage or cheese, natamycin also prevents unwanted fungi from spreading there. If you eat the correspondingly treated food, you naturally eat the antifungal agent.
Antifungal in cheese
Natamycin (E 235) was pre-tested and assessed by the Expert Committee on Food Additives (JECFA) before it was approved. After several increases, the level of safety (“Level causing no toxicological effects”) was finally set at a maximum of 200 milligrams per person and day or 3 milligrams per kilogram of body weight.
The Scientific Committee on Food of the EU Commission (Scientific Committee on Food, SCF) considered natamycin to be acceptable on cheese and sausage casings if only the finished product was treated with natamycin and the residues on the surface do not exceed one milligram per square decimeter. 5 millimeters below the surface, natamycin must no longer be detectable.
German experts criticize limited values
German experts assess these values considerably more critically than those responsible in the EU. The Federal Institute for Risk Assessment (BfR) agreed to the use of natamycin in cheese. However, they did not consider it necessary to treat the surface of sausage casings. From a microbiological and technological point of view, according to the German authority, there is no need to use an antifungal.
Not every cheese has to be labeled
Natamycin has to be labeled in the list of ingredients of a ready-made cheese. However, types of cheese that are offered loose at the cheese counter do not have to be labeled. Here it remains unclear whether the cheese was treated with antifungal agents or not.
Cheese rind – always cut with 5 millimeters of cheese
The statement “rind is not fit for consumption” conveys to the customer that the waxy coating is inedible and should therefore be removed. However, the consumer does not know that he would also have to cut off at least five millimeters from the cheese to protect himself from taking the antifungal. Yes, even types of cheese that do not have a visible rind can be treated with natamycin.
With regular consumption of appropriately treated food, one takes small amounts of the antifungal agent again and again. In this way, natamycin can damage the intestinal flora and also promote the development of resistance in fungi. So if you get a fungal infection in the future, the natamycin might not work as well.
The World Health Organization (WHO) also found in a study that even these small amounts of natamycin, which you consume with sausage and cheese, contribute to attacking the intestinal flora.
Doctors are now also demanding a warning on the cheese, which should point out the risk of breast cancer.