Aflatoxin M1 in UHT and powder milk marketed in the northern area of Morocco

Abstract

Aflatoxins are secondary metabolites produced by some species belonging to Aspergillus genus. They are considered as natural contaminants in feed and food products. The present study investigates the presence of mycotoxins in milk; it offers an evaluation of aflatoxin M1 (AFM1) occurrence in UHT and powder milk. The method applied for AFM1 analysis in milk was first validated and then used to determine the AFM1 levels in UHT milk (n = 40) and powder milk (n = 7) samples collected from supermarkets and dairy companies in both Tangier and Tetouan cities (northern area of Morocco). AFM1 was determined in milk samples using liquid chromatography coupled to fluorescence detection after immuno-affinity clean up. Validation step showed that the method used was linear at concentrations ranging between 10 and 160 ng/kg; it was reproducible and provided a recovery rate ranging between 99.5% and 114.6%. Analytical results showed that AFM1 was detected in 14 out of 40 UHT milk samples (35%) with an average concentration of 14.76 ± 10.21 ng/kg and detected in all the 7 powder milk samples (100%) with an average concentration of 25.50 ± 12.06 ng/kg. None of the analyzed samples exceeded the maximum limit sets by both Moroccan and European regulations in liquid and powder milk. Based on the results of this study, the consumer seems to be exposed to a lower risk of AFM1. However, a monitoring program should be implemented and enforced.