Aflatoxin monitoring in Italian hazelnut products by LC-MS

Hazelnut samples of different origin were collected in stores in Northern Italy and analysed for aflatoxin (AF) contamination by a sensitive chromatographic method on the basis of a tandem mass spectrometer with electrospray ionisation. The effects of two extracting solvent mixtures (methanol/water and acetonitrile/water) and different extraction times were tested and compared in terms of recovery. Analysis showed that 35 out of 93 samples (37.6%) were contaminated by AFs. The incidence of positive samples was higher in Turkish (66.7%) than in Italian samples (35.9%). Mean AF contamination was higher (p = 0.045, Kruskal-Wallis test) in the Turkish samples (0.33 µg kg(-1)) compared to the Italian (0.14 µg kg(-1)) ones. In both cases, however, a low level of total AF contamination was found in the positive samples (0.64 µg kg(-1)), both being far below the maximum limit set in European legislation.