Determination of Aflatoxins and Ochratoxins in Sicilian Sweet Wines by High-Performance Liquid Chromatography with Fluorometric Detection and Immunoaffinity Cleanup

Abstract

Ochratoxin A is the only mycotoxins with legal limits in the European Union for wine, by contrast, there is no EU legislation imposed for Aflatoxins and Ochratoxin B. A reproducible and sensitive analytical method for six mycotoxins: Ochratoxin A, Ochratoxin B, Aflatoxins B1, Aflatoxin B2, Aflatoxin G1 and Aflatoxin G2 was developed by using immunoaffinity column cleanup and HPLC-FLD method in 30 sweet wines produced in Sicily. This typical type of wine is manufactured from grapes grown in warmer climates, which have a higher sugar content; also, the over-ripening and the drying process of the grapes before fermentation conditions are responsible for the particular susceptibility of these berries to contamination by mycotoxins producing fungi. Results revealed the presence of Ochratoxin A in 96.6 % and of Ochratoxin B in 83.3 % of the samples examined (mean 0.246 and 0.168 μg/l, respectively). None of the samples showed a contamination exceeding the EU limit (2 μg/kg). Nine of tested wines were found to contain Aflatoxins with concentrations ranging from below LOD values to 0.068 μg/l. The results showed a very low incidence of Ochratoxins and Aflatoxins in analyzed wines, confirming the high degree of quality and safety of Sicilian sweet wines.