Evaluation of Aflatoxin M₁ enrichment factor in different cow milk cheese hardness category

Aflatoxin M¹ (AFM₁) is a hepatocarcinogenic and genotoxic derivative of aflatoxin B₁ excreted into milk after ingestion of feed contaminated by Aspergillus genus fungi. Because of the important role of dairy products, especially cow cheese, in the human diet, there is great concern about the presence of AFM₁ in this food category. EC Regulation No. 1881/2006 establishes the importance of the enrichment factor (EF), an essential parameter that must be defined in order to evaluate the maximum level of the toxin in cheese aiming to ensure that cheese has been produced from compliant milk. The Italian Ministry of Health has established two provisional AFM₁ EFs (5.5 and 3.0) to be applied to as many cheese categories (hard and soft), defined according to the moisture content on a fat free basis (MFFB) classification. Two experimental productions of Primosale and Fior di Latte cheese, both belonging to the soft cheese category, showed an EF of 4.1 and 2.9 respectively. Data in literature also suggest that the EF attribution based on the current categorization may need reconsideration.