Rheological and Microbiological Characteristics of Hops and Hot Trub Particles Formed during Beer Production

Molecules

Marek Zdaniewicz¹  Katarzyna Wolny-Koładka²  Monika Sterczyńska³ 

[1] Department of Fermentation Technology and Microbiology, University of Agriculture in Krakow, Balicka 122, 30-149 Krakow, Poland;Department of Microbiology and Biomonitoring, University of Agriculture in Krakow, Mickiewicza Ave 24/28, 30-059 Krakow, Poland;Faculty of Mechanical Engineering, Department of Food Industry Processes and Facilities, Koszalin University of Technology, 15-17 Raclawicka, PL75620 Koszalin, Poland;

关键词: hop pellets;    Polish hops;    hot trub;    rheology;    viscosity;    waste;   

DOI  :  10.3390/molecules26030681

来源: DOAJ

【 摘 要 】

During the production of beer, and especially beer wort, the main wastes are spent grain and hot trub, i.e., the so-called “hot break.” Combined with yeast after fermentation, they represent the most valuable wastes. Hot trub is also one of the most valuable by-products. Studies on the chemical composition of these sediments and their rheological properties as waste products will contribute to their effective disposal and even further use as valuable pharmaceutical and cosmetic raw materials. So far, hot trub has been studied for morphology and particle distribution depending on the raw material composition and beer wort extract. However, there are no preliminary studies on the rheological properties of hot trub and hops. In particular, no attention has yet been paid to the dependence of these properties on the hop variety or different protein sources used. The aim of this study was to examine the effect of different hopping methods on hot trub viscosity and beer wort physicochemical parameters. Additionally, the hop solutions were measured at different temperatures. A microbiological analysis of hop sediments was also performed to determine the post-process survival of selected microorganisms in these wastes. For manufacturers of pumps used in the brewing industry, the most convenient material is that of the lowest viscosity. Low viscosity hot trub can be removed at lower velocities, which reduces costs and simplifies washing and transport. The sediments also had similar equilibrium viscosity values at high shear rates.

【 授权许可】

Unknown