The aim of the master's thesis was to study the effect of the Aromazyme preparation on the release and biotransformation of aromatic compounds from hops into beer, focusing on monoterpene alcohols. In the practical part, we conducted 3 fermentation experiments, where we used 2 strains of yeast and 2 forms of hops and monitored various parameters. In the first fermentation experiment, we observed the difference in beta-glucosidase activity by measuring fluorescence in samples with the addition of the Aromazyme preparation (concentration in beer 5 g/hL and 10 g/hL) relative to the sample without addition. We found that a higher addition of the preparation had a more significant positive effect on beta-glucosidase activity, which changed during fermentation. In the second experiment, we evaluated the aromatic profile of beer by sampling at the time of preparation addition and at 2, and 4 days after the addition, using gas chromatography coupled with mass spectrometry (GC-MS). We noticed a slightly stronger negative effect of the enzyme preparation on the content of monoterpene alcohols in the case of Kveik yeast and a fermentation temperature of 30°C. The preparation mostly had a negative impact on the beer, causing a decrease in the content of aromatic compounds. The effect of the preparation also depended on the contact time, with a greater negative impact observed with longer dry hopping times using the CRYO form of hops. In the final fermentation experiment, intended for sensory analysis, we observed the effect of the amount of preparation during fermentation with Kveik yeast and the addition of CRYO hops. Due to an error in execution, the results were unusable, which was confirmed by physico-chemical analysis with the CDR BeerLab device. We did not confirm all hypotheses in the study. We rejected those hypotheses suggesting positive properties of using the preparation in beer. Nevertheless, we confirmed our predictions that the addition of the preparation does cause certain changes in beer.
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