Natural co-occurrence of ochratoxin A, ochratoxin B and aflatoxins in Sicilian red wines

The natural occurrence of ochratoxin A, ochratoxin B, aflatoxin B-1, aflatoxin B-2, aflatoxin G(1) and aflatoxin G(2) (OTA, OTB, AFB(1), AFB(2), AFG(1), AFG(2)) in red wines was investigated by HPLC/FLD after immunoaffinity column clean-up in 57 market samples produced in Sicily (Italy). The results showed a very low incidence of these mycotoxins in analysed samples, confirming the high degree of quality and safety of Sicilian red wines. The results indicated 71.9% and 64.9% positive samples for OTA and OTB respectively, with an average level of 0.13 mu gl(-1), well below the European maximum permitted levels (MLs). The aflatoxin most frequently detected in the samples was AFG(1), present in 57.9% of samples, while the other aflatoxins were rarely present. Recovery experiments were carried out on eight mycotoxin-free red wines spiked with OTA, OTB, AFB(1), AFB(2), AFG(1) and AFG(2) at two different levels. The limits of detection (LODs) in wines were 0.02 mu gl(-1) for OTA, 0.04 mu gl(-1) for OTB, 0.03 mu gl(-1) for AFG(1), AFG(2) and AFB(2), and 0.05 mu gl(-1) for AFB(1). A good correlation was found, with good performances in term of precision for the method.