Aflatoxin M1 contaminations in different types of cheese in Serbia

Abstract

Aflatoxin M1 (AFM1) is excreted into milk as the main metabolite of aflatoxin B1 and as such it poses a potential risk to human health. Accordingly, the analysis of AFM1 in milk and milk products is of great importance. The aim of this research was to investigate the AFM1 level in different types of cheese (soft cheese, processed cheese, fresh cheese, semi-hard cheese, parmesan, mozzarella, hard cheese) on the Serbian market. A total of 42 samples of cheese of different producers were collected from the domestic market. After extraction with dichlor-methane, cheese samples were prepared and analysed by ELISA test. Among the analysed 42 samples, 17 (40.5 %) were contaminated by AFM1 at levels ranging from 156.0 ng/kg to 810.0 ng/kg. The 15 samples (35.7 % of the samples) were contaminated by AFM1, at levels ranging from 54.0 ng/kg to 83.0 ng/kg and 10 samples (23.8 % of the samples) had undetectable AFM1 levels (<50 ng/kg). Based on these results, it could be concluded that 28.6 % (12/42) cheese samples had AFM1 concentration higher than EU maximum level (250 ng/kg), with concentrations between 263.0 and 810.0 ng/kg. The percentage of cheese samples with AFM1 levels exceeding the EU maximum AFM1 level was relatively high, indicating that the presence of AFM1 is still a big problem for producers in Serbia. The testing of raw milk used for cheese production is important for the protection of public health. Stricter measures should be taken to reach a satisfactory level of concentration. In addition, optimum storage conditions for animal feed should be provided, and animal feeding should be monitored for the presence of AFM1 and other aflatoxins.