Application of gamma-irradiation for destruction of aflatoxins in wheat four


Application of gamma-irradiation for destruction of aflatoxins in wheat four


Gergana Stamenova, Galya Valcheva, Petya Kovacheva
Faculty of chemistry and pharmacy, University of Sofia “St. Kliment Ohridski”, Bulgaria


Aflatoxins are mycotoxins, which are secondary metabolic products of Aspergillus flavus and Aspergillus parasiticus. The most important aflatoxins found in food and feed are: B1, B2, G1, G2. They have a carcinogenic, hepatotoxic and teratogenic effect, therefore control of their concentrations and prevention of their ingestion through food in humans and animals is essential. Various methods for reducing aflatoxin content are known: physical, chemical, and biological. They are to be applied in combination in order to reach the permitted concentration levels. The present study aims to establish the degree of aflatoxin destruction in flour after gamma-radiation with different doses. The experiment includes contamination of wheat flour with aflatoxins B1, B2, G1, G2 at concentrations between 4 and 12 μg/kg, gamma-irradiation with doses between 5 and 27 kGy and subsequent analysis with HPLC. The gamma-irradiation was carried out with the industrial gamma-irradiator BULGAMMA, based on the JS-850 60Co type gamma-irradiator at Sopharma AD. Doses applied to the irradiated samples were determined using ethanol-chlorobenzene dosimeters. The analysis was carried out according to BDS EN ISO 16050: Determination of aflatoxin B1 and the sum of aflatoxins B1, B2, G1, G2 in cereals and their products". The results obtained showed the highest degree of degradation of aflatoxin B2 and the lowest in aflatoxin B1 at the absorbed dose of 27 kGy. With low absorbed doses such as 5 kGy, between 10% destruction (for aflatoxin G2) and 40% destruction (for aflatoxin B2) was achieved.
Key words: aflatoxins B1, B2, G1, G2, flour, gamma-irradiation, HPLC