Screening and Quantitation of 191 Mycotoxins and Other Fungal Metabolites in Almonds, Hazelnuts, Peanuts, and Pistachios Using UHPLC/MS/MS Authors

This application note describes the development of a multitarget method for the determination of 191 mycotoxins and other fungal metabolites as well as its validation in almonds, hazelnuts, peanuts, and pistachios. In addition to all mycotoxins regulated in the European Union, the method includes many mycotoxins that are frequently found in food. The method comprises a simple extraction with an acidified acetonitrile-water mixture, a subsequent dilution of the raw extract, and measurement by UHPLC/MS/MS. Calibration was performed for all compounds with solvent standards. Furthermore, this application note presents parts of a validation for the 65 most important mycotoxins in the four tested matrixes. The method showed excellent sensitivity down to 0.04 μg/kg for enniatin B3 in peanuts, and good reproducibility with standard deviations below 10 % for the majority of analytes. Apparent recoveries of 70 to 120 % were obtained in approximately 60 % of the matrix-analyte combinations. In cases with lower recoveries, either extraction recoveries were low (for example, for fumonisins) or signal suppression was observed for several early eluting analytes. There was signal enhancement in a few cases, leading to higher apparent recoveries. The method was applied to the analysis of naturally contaminated nut samples and overall 40 different fungal metabolites could be identified. Interestingly, the most frequently found toxins were not the compounds currently regulated in the European Union but beauvericin, enniatin B, and macrosporin. The most contaminated hazelnut sample contained 26 different toxins. All results are presented in more detail in Varga et al. [1].