Degradation of Aflatoxin B1 during the Fermentation of Alcoholic Beverages

Aflatoxin B-1 (AFB(1)) is a contaminant of grain and fruit and has one of the highest levels of carcinogenicity of any natural toxin. AFB(1) and the fungi that produce it can also contaminate the raw materials used for beer and wine manufacture, such as corn and grapes. Therefore, brewers must ensure strict monitoring to reduce the risk of contamination. In this study, the fate of AFB(1) during the fermentation process was investigated using laboratory-scale bottom and top beer fermentation and wine fermentation. During fermentation, cool wort beer samples and wine must samples were artificially spiked with AFB(1) and the levels of AFB(1) remaining after fermentation were analyzed. AFB(1) levels were unchanged during both types of fermentation used for beer but were reduced to 30% of their initial concentration in wine. Differential analysis of the spiked and unspiked wine samples showed that the degradation compound was AFB(2a), a hydrated derivative of AFB(1). Thus, the results showed that the risk of AFB(1) carryover was still present for both types of beer fermentation but was reduced in the case of wine fermentation because of hydration.