Determination of aflatoxins, deoxynivalenol, ochratoxin A and zearalenone in organic wheat flour under different storage conditions

Samples of flour derived from an organic wheat seed cultivated in the region Abruzzo (Central Italy) were examined for detection of aflatoxins, deoxynivalenol, ochratoxin A and zearalenone after storage in presence of oxygen or under vacuum, for one year. They were analyzed by high performance liquid chromatography with fluorescence detection for aflatoxins, ochratoxin A and zearalenone and with diode array detector for deoxynivalenol. An immunoaffinity column cleanup was applied for all the compounds, except for aflatoxins determination which required a solid phase extraction. Recoveries (range 76%-107%) and within-laboratory reproducibility (RSD% < 10.3) met the performance criteria of Commission Regulation (EU) No 519/2014 amending Commission Regulation (EC) No 401/2006 for the detection of mycotoxins in foodstuffs. Analytes were below the detection limit of the method and this result was probably due the quality of organic seed and good agricultural practices performed for prevention of mycotoxin formation.