Fate and Development of Naturally Occurring Fusarium Mycotoxins During Malting and Brewing1

Abstract

There was widespread occurrence of Fusarium head blight and the mycotoxin deoxynivalenol (DON) on barley produced in Minnesota, North Dakota, and South Dakota during 1993. To study the fate of Fusarium mycotoxins during malting and brewing, five barley samples infested with Fusarium graminearum were selected from the 1993 crop in North Dakota. DON levels ranged from 4.8 to 22.5 μg/g of barley. Zearalenone (1.5 μg/ g) and 15-acetyldeoxynivalenol (15-ADON) (2.1 μg/ g) were detected on one of the samples. Steeping generally reduced the mycotoxin level to near the estimated level of detection. However, mold growth and production of DON occured during germination. DON levels in five-day green malts represented 18–114% of that present on the original barley. The magnitude of this variation suggests differences in mold viability or in the nature of infestation between individual samples. Zearalenone and 15-ADON also increased during germination. After brewing, 80–93% of the DON present on the malt grist was detected in the beer. A small amount of DON was detected on the spent grains. Zearalenone and 15-ADON were not detected in beer; 60 and 18% respectively, of the zearalenone and 15-ADON present on the malt grist was found in the spent grains.