In the beer production process, an important stage is the wort boiling process, which is very energy-intensive. During boiling, numerous changes occur that have a significant impact on the final quality of the product. As part of the Brewery Laško Union project (PLU), we attempted in our master's thesis to reduce evaporation and thus save energy by shortening the wort boiling time. We evaluated the impact of shorter boiling times on the properties of wort and beer (pH value, extract and alcohol content, color, bitterness content, foam stability, colloidal stability, sensory properties, and others). Special attention was given to the analysis of the volatile sulfur compound dimethyl sulfide (DMS), which negatively affects the beer's aroma in higher concentrations. The results of our experiment showed that by reducing the wort boiling time by 10 min, evaporation could be decreased by approximately 1%. For certain process parameters such as pH value, extract content, and alcohol content, no significant differences were observed between the samples with reduced boiling time and the reference samples. The effect of reduced evaporation on some variables was often not significant due to excessive variation between repetitions. The color of the beer was slightly more intense with longer boiling. Shorter boiling time contributed to greater bitterness and better foam stability in some samples. Shorter evaporation occasionally led to improved colloidal stability of the beer. The DMS content in the beer was lower than in the cold wort. A shorter boiling time had a positive impact on the DMS content. All process parameters of the wort and beer samples with reduced boiling time met the threshold values. We can conclude that reducing the wort boiling time by 10 min did not have a negative effect on the final quality and sensory evaluation of the beer.
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