One study found two mycotoxins in some packs of grated Grana Padano. Specifically, the paper found ochratoxin and sterigmatocystin, both produced by microscopic molds. The former was found in 48.6% of the cases analysed, while the latter was present in 94.4% of the packs of grated “grana” type cheeses sold in supermarkets. These would be small but significant quantities.
Precautionary limits
The data was shared by Terenzio Bertuzzi of the Catholic University of Piacenza, who published the study in the journal Toxins. The Grana Padano and Parmigiano Reggiano consortia directly financed the research. Sterigmatocystin is considered an “emerging” toxic substance, for which the European Union has not yet established maximum limits to be observed. For ochratoxin, however, specific authorized parameters already exist, which vary according to the food. In particular, the limits are 3, 10 and 15 micrograms per kilo respectively for cereals and derivatives, raisins and spices.
By themselves, the quantities of the two toxins found in the 107 samples analyzed are not dangerous, but their consumption can be added to that present in other foods such as cereals and derivatives, coffee, legumes, cocoa, dried fruit, wine, beer and cured meats. To understand the impact on health, therefore, the overall intake must be considered, the researchers emphasize. Overall, reports the Ansa agency, the risk for the consumer would be minimal, while the legal limits set by the EU would be purely precautionary.
Toxic molds and how to avoid them
Cheeses are prone to the growth of microscopic molds on the surface. During the long maturation of hard cheeses (at least 9 months for the parmesan), mold spores can settle on the surface of the wheels and produce mycotoxins. The problem only concerns grated cheeses, but the incidence should not be underestimated given that about a quarter of the parmesan produced in Italy is transformed and sold as grated cheese. The reason is that the rind is also grated in these packages, given that the regulation allows a maximum use of 18% of this part of the cheese.
Prevention practices have been identified to avoid the formation of these moulds. In the maturing warehouses belonging to the main protection consortia, for example, the cheeses periodically undergo a rind cleaning process resulting in the reduction of the levels of the two toxins in the grated product. “The reduction of contamination would be greater by removing more rind. The two protection consortia are safe for the consumer, but we need to monitor the entire sector”, concluded Bertuzzi.
