Behavior of Ochratoxin A in Brewing

Malt containing high levels (up to 52 μg/kg) of ochratoxin A (OA) was prepared on a pilot scale by inoculating malting barley with live Penicillium verrucosum. This malt was then used for pilot brewing trials to determine the extent to which OA can survive the brewing process. Substantial losses, up to 40% of the OA in the grist, were observed during mashing, most probably by proteolytic degradation. Another 16% was eliminated with the spent grains. Some losses of OA occurred during fermentation, but these were less than those in mashing. Overall, between 13 and 32% of the OA present in the original grist survived into the beer.