EFFECT OF GAMMA-IRRADIATION ON THE NATURAL OCCURRENCE OF FUSARIUM MYCOTOXINS IN WHEAT, FLOUR AND BREAD

A survey was carried out to obtain data on the occurrence of Furarium mycotoxin in wheat and flour samples collected from local markets in E gypt and to study the influence of gamma-irradiation on controlling th e occurrence of these mycotoxins in wheat, flour and bread. Deoxynival enol (DON) was detected in five samples of wheat at levels ranging fro m 103 to 287 mu g/kg and one sample each of flour and bread at concent rations 188 and 170 mu g/kg. Zearalenone (ZEN) was detected in ten sam ples of wheat at levels from 28 to 42 mu g/kg and four samples each of flour and bread at concentrations of 95 and 34 mu g/kg, respectively. T-2 toxin was detected only in one sample each of wheat, flour and br ead at concentrations of 2.9, 2.2 and 2.3 mu g/kg, respectively. Gamma -irradiation at dose level of 6 kGy completely eliminated fungal flora in flour and wheat. DON, ZEN and T-2 toxin concentrations are reduced to 85, 20 and 2.0 mu g/kg for wheat and to 125, 45, and 1.0 mu g/kg f or flour after 4 kGy exposure and a sharp drop in Fusarium toxin level s occurred at 6 kGy and was eliminated at 8 kGy. Bread prepared from 6 kGy was contaminated with Fusarium toxin at levels below 5 mu d/kg. I t was noticed that gamma-irradiation reduce greatly the natural occurr ence of Fusarium mycotoxins in bread.