Occurrence of Aflatoxins in Peanuts and Peanut Products Determined by Liquid Chromatography with Fluorescence Detection

Liquid chromatography with fluorescence detection using immunoaffinity column clean-up was a method described for determination of aflatoxins (AFB1, AFB2, AFG1 and AFG2) in peanuts and peanut based products. The validation of the procedure was performed. Good coefficient of correlation was found for all aflatoxins in the range of 0.9993–0.9999. Limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.003–0.005 mg/kg and 0.009–0.023 mg/kg, respectively, which was acceptable. The mean recovery for total aflatoxins was 88.21%. The method also showed acceptable precision values in the range of 0.171–2.626% at proposed concentration levels for all four aflatoxins. RSDR values (within laboratory reproducibility) calculated from the results showed good correlation between two analysts for all aflatoxins and they ranged from 4.93-11.87%. The developed method was applied for the determination of aflatoxins in 27 samples of peanuts and peanut based products. The results showed that 21 peanut samples (77.7%) were below LOD of the method. Three samples had positive results over the MRL. There was one extreme value recorded for the total aflatoxins in peanut (289.2 mg/kg) and two peanut based products, peanut snack and peanut, with total content of aflatoxins being 16.3 mg/kg and 8.0 mg/kg, respectively. The obtained results demonstrated that the procedure was suitable for the determination of aflatoxins in peanuts and peanut based products and it could be implemented for the routine analysis.