Tricothecenes and enzyme activities in the mashing step of the brewing process

The relation between contamination by trichothecenes, DON (Deoxyvalenol) and 15-ADON (15-acetil-deoxyvalenol), and enzymes, protease, β-amylase and α-amylase, in the mashing step was studied. Malted barley was subject to mashing at three temperature ramps, which resulted in enzyme extracts. Enzyme activity of the extract was evaluated in a model solution with DON and 15-ADON. Results indicated that activities of protease and β-amylase are changed by trichothecenes. Reduction in 15-ADON concentration was 100% when the initial concentration was 0.23 µg mL^-1 and 74, 72 and 92% when it was 0.85 µg mL^-1, under activities of protease, β-amylase and α-amylase, respectively. On the other hand, DON concentration increased 45 and 30% under protease and β-amylase activities, respectively. Malt contamination by DON and 15-ADON can affect enzyme activity and modify the process yield, which may cause economic losses.