Identify the natural levels of mycotoxins in Egyptian roasted peanuts and the destructive effect of gamma radiation

Abstract

A total of 36 roasted peanut samples were collected from 12 regions at 4 Egyptian governorates (Cairo, Giza, Alexandria and El-Faiyum) during 2017. Aflatoxins (B1, B2, G1 and G2), ochratoxin A and zearalenone were determined in the collected samples using HPLC. Seventy five percent of samples were contaminated with aflatoxins. Aflatoxin B1 was the most dominant type, whereas aflatoxin G2 was found only in two samples at low levels. Samples were completely ochratoxin A and zearalenone-free. Quantitative results revealed that the samples of Al-Manshieh region at Alexandria governorate had the highest averages of aflatoxins B1, B2 and G2 (33.15, 3.66 and 0.22 μgkg-1, respectively), while Al-Ajami samples at the same governorate had the highest average of aflatoxin G1 as 2.83 μgkg-1. Likewise, samples from Dokki at Giza governorate had high levels of total aflatoxins recording 26.33 μgkg-1. Regarding to the effect of gamma radiation on aflatoxin B1, the doses of 5, 10 and 20 kGy were studied. The reduction levels of aflatoxin B1 varied according to the spiking levels and dose of gamma radiation. The dose 5 KGy was ineffective, whereas, a significant reduction in AFB1 was noticed using 10 and 20KGy recording > 26.7% reduction notably in samples spiked with 20 μgkg-1 AFB1 and treated with 20 KGy (59% reduction).