Density Segregation of Corn and Wheat Naturally Contaminated with Aflatoxin, Deoxynivalenol and Zearalenone

Abstract

Density segregation was used to reduce mycotoxin levels of corn samples naturally contaminated with aflatoxin or deoxynivalenol, and wheat samples naturally contaminated with deoxynivalenol or zearalenone. Corn kernels which were buoyant in saturated sodium chloride represented 3% of the total sample, yet contained 74% of the aflatoxin. Corn buoyant in water contained 51 and 14% of the total deoxynivalenol present in two naturally contaminated corn samples. Subsequent segregation of corn non-buoyant in water with 30% sucrose removed additional deoxynivalenol-contaminated kernels, resulting in the combined removal of 59 and 79% of the deoxynivalenol. Removal of deoxynivalenol-contaminated corn kernels with both water and 30% sucrose reduced the concentration of deoxynivalenol by 53 and 77%. Removing wheat buoyant in water and 30% sucrose decreased the deoxynivalenol present by 96 and 68%, and reduced the deoxynivalenol concentration by 96 and 67%. Removing wheat naturally contaminated with zearalenone buoyant in water and 30% sucrose combined resulted in no detectable zearalenone remaining in the non-buoyant fraction of the samples.