Occurrence of zearalenone in grains and its reduction by gamma radiation

Abstract

ABSTRACTPurpose: The purpose of the present study was to examine the reduction of Zearalenone (ZEA) in grains by using gamma radiation (γ- ray) to minimise exposure hazards and of economic and health consequence.Materials and Methods: A total of 150 samples of food grains (wheat, yellow corn, and white corn) were collected from Egyptian retail markets from five governorates (Cairo, Alexandria, Giza, Qena and Gharbia) to determine the ZEA contamination levels by high performance liquid chromatography (HPLC). To study reduction by γ- ray, twelve uncontaminated samples were spiked with ZEA at the maximum permitted limit (100 µg/kg) and irradiated with different energies of γ-rays (5, 10, 15 and 20 kGy), and then the reduction rates were evaluated.Results: Only two samples out of 150 randomly collected samples were found to be contaminated with ZEA. In the case of the effect of γ-rays on grain ZEA contents, the reduction in ZEA ranged between 49.0 ± 4.7 and 97.0 ± 1.5% in wheat samples, and between 24.8 ± 4.1 and 51.1 ± 3.5% in yellow corn samples, between 20.3 and 59.9% in white corn samples. Finally, at 20 kGy, the reductions were 97.0 ± 1.5, 51.1 ± 3.5 and 59.9 ± 3.2% in wheat, yellow corn and white corn, respectively.Conclusions: ZEA was more easily degraded in wheat than in yellow corn and white corn. Moisture content played a vital role in ZEA degradation. γ- Ray exposure was used as an effective method to reduce ZEA in wheat, yellow corn and white corn. The reduction rate increased relative to the irradiation dose. Further study is recommended to determine the reduction yields and toxicities of ZEA that may be achieved post γ- ray radiation.