The paper concerns a study of drying and the creation of a statistical model for measuring the relative humidity of the drying environment in a belt dryer, as well as the moisture content of hop heads, stems, and bracts. The SAAZ variety was used, which is widely cultivated in the Czech Republic, and the data from harvesting seasons since 2017 were recorded. The findings demonstrated the influence and dependence of the moisture content of hop cones and their parts on the relative humidity of the drying environment in a belt dryer of hops. This dependence was confirmed by a statistical analysis of the measured values. Furthermore, a quadratic model was developed based on measurements taken over three harvest seasons. The model is applicable to predict the moisture content of the hops at a given location based on the relative humidity of the drying environment in the belt dryer and could be useful for developing an automatic hop-drying system.

Faculty of Economics and Management Department of Statistics Czech University of Life Sciences Prague Kamýcká 129 CZ165 00 Praha Czech Republic

Faculty of Engineering Department of Agricultural Machines Czech University of Life Sciences Prague Kamýcká 129 CZ165 00 Praha Czech Republic

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