Evaluation of Aflatoxin M1 Enrichment Factor in Semihard Cow's Milk Cheese and Correlation with Cheese Yield

Assessment of aflatoxin M1 enrichment factor in cheese produced with naturally contaminated milk

Aflatoxin M1 (AFM1) is a well-known carcinogenic compound that may contaminate milk and dairy products. Thus, with the regulation 1881/2006, the European Union established a concentration limit for AFM1 in milk and insisted on the importance of defining enrichment factors (EFs) for cheese. In 2019, the Italian Ministry of Health proposed four different EFs based on cheese's moisture content on a fat-free basis (MMFB) for bovine dairy products. This study aimed to define the EFs of cheese with different MFFB. The milk used for cheesemaking was naturally contaminated with different AFM1 concentrations. Results showed that all the EF average values from this study were lower than those of the Italian Ministry of Health. Hence, the current EFs might need to be reconsidered for a better categorization of AFM1 risk in cheese.

Probabilistic modeling and risk characterization of the chronic aflatoxin M1 exposure of Hungarian consumers

Aflatoxin contamination can appear in various points of the food chain. If animals are fed with contaminated feed, AFB1 is transformed-among others-to aflatoxin M1 (AFM1) metabolite. AFM1 is less toxic than AFB1, but it is still genotoxic and carcinogenic and it is present in raw and processed milk and all kinds of milk products. In this article, the chronic exposure estimation and risk characterization of Hungarian consumers are presented, based on the AFM1 contamination of milk and dairy products, and calculated with a probabilistic method, the two-dimensional Monte-Carlo model. The calculations were performed using the R plugin (mc2d package) integrated into the KNIME (Konstanz Information Miner) software. The simulations were performed using data from the 2018-2020 food consumption survey. The AFM1 analytical data were derived from the Hungarian monitoring survey and 1,985 milk samples were analyzed within the framework of the joint project of the University of Debrecen and the National Food Chain Safety Office of Hungary (NÉBIH). Limited AFM1 concentrations were available for processed dairy products; therefore, a database of AFM1 processing factors for sour milk products and various cheeses was produced based on the latest literature data, and consumer exposure was calculated with the milk equivalent of the consumed quantities of these products. For risk characterization, the calculation of hazard index (HI), Margin of Exposure, and the hepatocellular carcinoma incidence were used. The results indicate that the group of toddlers that consume a large amount of milk and milk products are exposed to a certain level of health risk. The mean estimated daily intake of toddlers is in the range of 0.008-0.221 ng kg-1 bw day-1; the 97.5th percentile exposure of toddlers is between 0.013 ng kg-1 bw day-1 and 0.379 ng kg-1 bw day-1, resulting in a HI above 1. According to our study, the exposure of older age groups does not pose an emergent health risk. Nevertheless, the presence of carcinogenic compounds should be kept to a minimum in the whole population.

A Study of the Occurrence of Aflatoxin M1 in Milk Supply Chain over a Seven-Year Period (2014-2020): Human Exposure Assessment and Risk Characterization in the Population of Central Italy

Aflatoxin food contamination represents a rising global issue that will continue to increase due to climate change. Aflatoxin M1 (AFM1) is of high concern for the whole dairy industry. In light of AFM1′s harmful potential, a human health exposure assessment and risk characterization were performed for all age populations of central Italy with regard to milk and cheese consumption by means of the margin of exposure (MOE). In total, 16,934 cow and ewe’s milk samples were collected from 2014 to 2020 and analyzed by an enzyme-linked immunosorbent assay (ELISA) screening method, confirmed by high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The average concentration of AFM1 in cow’s milk ranged from 0.009 to 0.015 µg/kg, while in ewe’s milk, the average concentration ranged from 0.009 to 0.013 µg/kg. The average amount of AFM1 exposure ranged from 0.00005 to 0.00195 g/kg bw/day, with the main contributor represented by drinking milk, followed by the consumption of soft cheeses. A high level of public health concern related to the youngest consumers has arisen from risk characterizations highlighting the need for constant monitoring of AFM1′s occurrence in milk by inspection authorities, alongside regular updates with regard to exposure assessments.

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.