Decontamination of aflatoxin B1-contaminated corn by ammonium persulphate during fermentation

The decontamination of aflatoxin B-1 (AFB(1))-contaminated corn, which is required if the corn is to be suitable for alternative use, by an ammoniation-fermentation integrated process was studied. This process could be used for the production of fuel ethanol from aflatoxin-containing corn. Different concentrations (0.25, 0.50, 1.00, 1.5 and 2.0% w/w) of ammonium persulphate were tested in the detoxification of AFB(1)-contaminated corn during fermentation. In order to increase the decontamination of corn, 0.5 and 1.0% (w/w) azodicarbonamide, benzoyl peroxide and hydrogen peroxide were tested. Peroxides were added at three different stages of the fermentation process: liquefaction, saccharification and fermentation. Levels of AFB(1) and ethanol were determined after each fermentation process. Treated corn was tested for mutagenic potential using the Ames test with TA100 tester strain and pure AFB(1) as positive control. Addition of 2.0% (w/w) ammonium persulphate caused the highest level of decontamination without affecting ethanol production. Addition of peroxides did not significantly (P < 0.05) increase ethanol production or significantly (P < 0.05) improve the decontamination process. The best processes for decontamination of corn and for ethanol production included the addition of 2.0% (w/w) ammonium persulphate for both and of 1.0 and 0.5% (w/w) benzoyl peroxide respectively. All treated corn samples showed no mutagenic potential. Possible industrial use of these processes is discussed. (C) 2002 Society of Chemical Industry.