Laboratory of Brewing and Malting

Our laboratory deals with education, research, and development in the fields of brewing and malting. Research activities investigate:

Health-promoting compounds in brewing raw materials (hops, barley and beer
Microbiological, colloidal, and sensorial stability of beer
Microbial contaminants in beer and raw materials
Authentication of beer and brewing raw materials
Study of the properties of brewing yeast
Formation, stability, and decomposition of beer foam
Development of new products
Development of new analytical methods

Research group members

Main Research Topics

Increasing the Shelf Life of Unfiltered Beers

A consequence of increasing the production of unfiltered beer is the need for a significant extension of their shelf lives. For this purpose, we test the use of high hydrostatic pressure in plastic barrier packages. Moreover, we are also investigating the development and subsequent application of modular flow minipasterizeur for use in micro- and mini-breweries.

Increasing the Colloidal Stability of Czech Beers

Czech beers have higher polyphenol content and polypeptides than many other beers, and thus they tend to form colloidal haze. Colloidal stabilization is typically used for the sorption of synthetic stabilizers to extend shelf lives. We have developed a new generation of adsorbents capable of removing one of the precursors to colloidal haze. For this purpose, waste materials from the production of hop extracts and pellets are also being tested, which combines the advantages of increasing colloidal stability and preserving the antioxidant effects of beer.

Development of Bottom Yeast Strains with Improved Technological Properties

As a result of an expression of the cell wall, yeast with inserted genes produces anchored proteins with two functions. The first is a higher affinity towards polyphenolic compounds, where a microorganism may serve as an agent for increasing the colloidal stability of beer. The second protein is an enzyme catalysing the conversion of 2-acetolactate to acetoin. Accelerating this reaction would greatly simplify the process of maturing and reduce the risks associated with excessive levels of diacetyl, which causes a buttery flavour in beer. This research is conducted in collaboration with the Department of Biochemistry and Microbiology.

Biologically Active Substances of Hops

Used in folk medicine for several thousand years, hops contain substances with various beneficial health effects. These substances, which are also found in beer, can be isolated from hops and used in food supplements and final-stage drugs. Currently, we are testing methods related to the isolation and biotransformation of prenylated flavonoids (in particular, xanthohumol and 8-prenylnaringenin), including their strong phytoestrogenic properties that should facilitate their application in the suppression of menopausal symptoms.

Study of Beer Foam and Prediction of Gushing and the Possibilities of Its Suppression

Beer foam and beer foam stability are important organoleptic characteristics associate with beer but with a significant negative effect: gushing. Research into gushing includes methods for studying the causes and intensity of this phenomenon and the study of hydrophobins, primary triggers of gushing. We have developed a pressure column that enables our research of this complex phenomenon. We aim to develop a better understanding of the fundamental mechanisms of gushing and create proposals for its suppression (applying parasitic fungi to suppress the contamination of microflora in malt, which forms hydrophobins).

Study of Microbial Contamination in Breweries

The most widespread forms of contamination in breweries involve a microbial consortium form of biofilms. The scope of the project is to identify anaerobic beer spoilage bacteria (particularly from the Pectinatus and Megasphaera families) and experimentally study how they adhere to their chosen representatives on solid surfaces. By understanding the adhesion mechanism used by these species, we hope to develop new methods for suppressing adhesion or for increasing the effectiveness of the cleaning of surfaces in food processing plants.

Development of New Analytical Methods and Their Validation

Each beer is unique, and, because of this, we can analyse the composition and content of individual volatile compounds that characterize the origin of the raw materials used to produce it, its age, and immediate sensory conditions. We can even predict changes to a beer over time. New methods for conducting such analysis are being developed, mainly based on solid-phase microextension (SPME-GC-MS) for the determination of higher alcohols, esters and acids, and terpene compounds. Newly developed methods are then used to solve other research topics for the entire laboratory.

Use of Innovative Microorganisms for the Production of Beer

Increasing market competition has led breweries to expand the assortment of beers they offer. One promising possibility for the development of new products is the use of innovative microorganisms during the fermentation process. One such group of microorganisms is probiotics, which are beneficial to human health, improving immunity, and maintaining a balance of intestinal microflora. The aim of this research is to obtain a set of microorganisms with probiotic properties that are able to ferment brewing wort and/or to tolerate an environment of traditional and non-alcoholic beer without reducing viability. We are also studying the fermentation capacity of selected microorganisms, the formation of flavour compounds, and the effect of the presence of microorganisms on non-traditional beer flavour and colloidal stability.

Collaboration

Updated: 26.2.2019 12:54, Author: Martin Halecký

Selected Results

Prusova N., Dzuman Z., Jelinek L., Karabin M., Hajslova J., Rychlik M., Stranska M.: Free and conjugated Alternaria and Fusarium mycotoxins during Pilsner malt production and double-mash brewing, Food Chemistry, 369, 130926, doi.org/10.1016/j.foodchem.2021.130926, (2022) IF 7,514 (on-line)

Karaoglan S.Y., Jung R., Gauthier M., Kincl T., Dostálek P.: Maltose-Negative Yeast in Non-Alcoholic and Low-Alcoholic Beer Production. Fermentation 8(6), 273, (2022), IF 5,123 (on-line)

Karabín M., Haimannová T., Fialová K., Jelínek L., Dostálek P.: Preparation of Hop Estrogen-Active Material for Production of Food Supplements. Molecules 26(19), 6065 (2021) IF 4,411 (on-line)

Kinčl T., Dostálek P., Brányik T., Olšovská J.: High-gravity brewing without adjuncts - The effect on beer parameters. LWT-Food Science and Technology 148, 111755 (2021) IF 4,952 (on-line)

Štulíková K., Bulíř T., Nešpor J., Jelínek L., Karabín M., Dostálek P.: Application of High-Pressure Processing to Assure the Storage Stability of Unfiltered Lager Beer, Molecules, 25, 2414, (2020), IF 3,267 (on-line)

Nešpor J., Karabín M., Štulíková K., Dostálek P.: An HS-SPME-GC-MS Method for Profiling Volatile Compounds as Related to Technology Used in Cider Production, Molecules, 24, 2117, (2019), IF 3,06 (on-line)

Nešpor J., Andrés-Iglesias C., Karabín M., Montero O., Blanco C. A., Dostalek P.: Volatile compounds profiling in Czech and Spanish lager beers in relation to used production technology, Food Analytical Methods, 12(10), 2293-2305, (2019), IF 3,413 (on-line)

Postulkova M., Rezanina J., Fiala J., Ruzicka M.C., Dostalek P., Branyik T.: Suppression of fungal contamination by Pythium oligandrum during malting of barley. Journal of the Institute of Brewing 124, 336-340 (2018), IF 0,868 (on-line)

Nešpor J., Karabín M., Hanko V., Dostálek P.: Application of response surface design to optimise the chromatographic analysis of volatile compounds in beer. Journal of the Institute of Brewing 124 (3), 244-253 (2018), IF 0,868 (on-line)

Karabín M., Hanko V., Nešpor J., Jelínek L., Dostálek P.: Hop tannin extract: A promising tool for acceleration of lautering. Journal of the Institute of Brewing (2018), 124, 374-380, IF 0,868 (on-line)

Carvalho D.O., Paulu A., Dostálek P., Guido L.F.: Measurement of catechin-7-O-glucoside from barley to malt. Journal of the Institute of Brewing (2018), 124, 359-364, IF 0,868 (on-line)

Krausová I., Mizera J., Dostále, P., Řanda Z.: Non-destructive determination of nitrogen in malting barleys by instrumental photon activation analysis and its comparison with the Dumas method. Journal of the Institute of Brewing 124 (1), 4-8 (2018), IF 0,868 (on-line)

Štulíková K., Karabín M., Nešpor J., Dostálek P.: Therapeutic perspectives of 8-prenylnaringenin, a potent phytoestrogen from hops. Molecules 23 (3), 660, 1-13 (2018), IF 3,098 (on-line)

Karabín M., Jelínek L., Kotrba P., Cejnar R., Dostálek P.: Enhancing the performance of brewing yeasts. Biotechnology Advances 36 (3) 691-706 (2018), IF 11,452 (on-line)

×