Analysis of aflatoxin M1 and M2 in commercial dairy products using high-performance liquid chromatography with a fluorescence detector

Aflatoxin M1 (AFM1) and M2 (AFM2) in commercial dairy products were analyzed by high-performance liquid chromatography (HPLC) with a fluorescence detector (FLD). To ensure an accurate analysis, two derivatization methods, bromination and aflatoxin–trifluoroacetic acid derivatization (ATD), were compared. The limits of detection (LODs) of the bromination method were 124.42–151.73 ng/kg, and the recovery rates were between 64 and 102%. The detection rates and concentration levels of AFM1 were 6–74% and 14.48–270.94 ng/kg, respectively. AFM1 was detected in 74% of milk powder samples and 36% of ice cream samples. The mean values of AFM1 in milk powder and ice cream samples were 270.94 and 33.16 ng/kg, respectively. In the case of AFM2, the detection rates were 2–10%, and the concentration levels were 20.62–55.67 ng/kg in milk and milk powder. Among milk and milk powder samples, ultra heat-treated (UHT) milk had lower AFM1 contamination levels than pasteurized milk.