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Health effects of Czech beer
Bokrová, Jitka ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis was to study physiological effect of various kinds of lager beer and to compare these effects in Czech beer and several beers produced in foreign countries. In theoretical part Czech beer characteristics and biologically active compounds in beer are described. Quantification of total phenolics, total flavonoids, antioxidant activity and bitter substances was performed photometrically. The quantity of vitamin C was determined by high performance liquid chromatography with spectrophotometrical detection. Beer buffering capacity was analyzed by pH measurement in artificial stomach and intestinal liquid, respectively. Analysis of physiological effect was accomplished by analysis of proteolytic enzyme activity. The total of 22 samples (16 Czech and 6 foreign lager beers) was studied. In these samples levels of basic technological characteristics and buffering capacity were compared. Alcoholic and non-alcoholic beers were compared too. According to experimental data it was confirmed that consumption of Czech beer (mainly lager beer) positively influences digestion process and activity of digestive proteolytic enzymes.
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Analysis of flavonoids in beer by LC-MS
Měřínská, Radana ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Presented diploma thesis is focused on analysis of phenolic compounds in various types of beers. The aim of this work was to find possible differences among several types of beers and also between Czech beers and beers of foreign production. Theoretical part contains detailed description of beer technology, review of important analytical methods for determination of phenolic compounds and total antioxidant activity. The main attention is focused on instrumental technique LC/MS. In the experimental part values of total phenolics and total flavonoids and results of antioxidant status in analyzed beers were determined spectrophotometrically. Basic brewing characteristics were determined by pycnometry. On-line liquid chromatography with photo diode array detection and mass spectrometry detection was used for identification and quantification of individual phenolic compounds. Spectrophotometric analysis of phenolic and flavonoid levels seems to be less specific, that is consistent with findings in accessible literature. It was proved, that iso- bitter compounds exhibit about 65.44 – 90.93 % of the total bitter substances. These components are responsible for the main part of beer bitterness. The HPLC/PDA/ESI-MS was necessary to use for determination of characteristic phenolic compounds in individual types of beer. Within our measurement three columns were tested, the most favourable results were obtained using the column Restek C18. When compared with foreing beers, in Czech beers higher level of majority of phenolic compounds was detected and specific distribution of individual derivatives was found as well.
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Determination of selected parameters in the Czech lager beer
Žáková, Kateřina ; Gregor,, Tomáš (referee) ; Diviš, Pavel (advisor)
The topic of this bachelor thesis is to establish an concentration of selected substances at czech beers lager type. In the first part of the work there are in a range of the theory described basic materials for a beer production and its production proces too. A large part is dedicated to describing of analytical methods used for an analysis of choosen phenolic substances, organic acids and inorganic substances (elements). In the experimental part the measured results are discussed. The target of this work was to compare a composition and to find specific or characteristic ingredients in selected brands type lager produced in Czech republic. Further there were compared the samples with the Czech Beer designation and the samples without those signing.
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Characterization of active substances in several kinds of beer
Benešová, Pavla ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis is to analyse biologically active compounds, especially of phenolic character, in 10 kinds of alcohol-free beer in comparison with alcoholic beer. In theoretical part basic steps of brewery technology are described including alcohol-free beer production. Characteristic compounds occurring especially in Czech beer e.g. proteins, phenolics, bitter substances and also methods for their analysis are discussed as well. Microfluidic electrophoresis (Experion, BioRad) was used to beer protein analysis. Phenolic compounds, flavonoids, technological characteristics and antioxidative activity were measured by spectophotometry. Individual phenolics of selected beers were identified and quantified by LC/ESI-MS analysis too. In alcohol-free beers similar concentrations of biologically active compounds were found in comparison with alcoholic beers, especially in the case of beer phenolics.
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Study some active substances in Czech beer
Pařilová, Kateřina ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
The aim of this work was to study phenolics and other active compounds in 22 kinds of lager beer and especially to find some differences between Czech beer and beers made in foreign countries. In theoretical part the most useful methods for phenolic and protein analysis are discussed. Further, basic steps of brewery technology are introduced and main beer components with regard to Czech beer specificity are presented. Analysis of total phenolics, total flavonoids, antioxidant activity and most of basic technological characteristics was performed spectrophotometrically. To identification and quantitative analysis of individual phenolics on-line liquid chromatography with photo-diode array (PDA) and mass spectrometry (MS) detection was used. Protein analysis was performed by vertical electrophoresis SDS-PAGE and by Experion microfluidic electrophoresis (BioRad). From the total of 22 samples, 15 Czech beers and 7 beers of foreign marks were enrolled into this study. In these samples levels of brewery characteristics, group antioxidants and individual phenolics were compared. Flask and can beers as well as alcoholic and non-alcoholic beers were compared too. As a model comparative sample the Czech hop of Sládek variety was used. Finally, usefulness of tested parameters to differentiation composition and technology of individual beer samples was evaluated and parameters suitable for Czech beer authenticity analysis were proposed.
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Pivovarské technologie v ČR a ve světě
Hambálková, Pavlína
The bachelor's thesis focuses on beer production technology in the Czech Republic and around the world. It is divided into theoretical and practical parts. The theoretical part describes the history of beer from its origins to the present day. The production technology is elaborated, including the raw materials and processes used. It particularly focuses on the phenomenon of Czech beer, its characteristics and uniqueness compared to other products. The practical part presents data from sensory and analytical measurements of selected bottom-fermented beers. The aim of the thesis was to analyze the literature and compare the quality of Czech lagers with a group of foreign beers. The highest rating in sensory analysis was awarded to Pilsner Urquell, which had the most points in all selected parameters, positively correlating with the quality of raw materials and production technology of this beer and the popularity of Czech lagers in our country.
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Nové možnosti a technologie ve výrobě piva
Čechová, Kateřina
The bachelor thesis is focused on new ways of using raw materials in the brewing in-dustry and new innovations. The theoretical part mentions basic raw materials for beer production, special types of malt, solid adjuncts from other raw materials, especially pseudocereals, liquid adjuncts, various methods of processing hops and new proce-dures or new equipment in beer production. Also the principle of production of Czech beer and European beer is compared. In the second part, the possibility of using star-chy surrogates was investigated. A recipe was created using buckwheat and then the sensory profile of the beer was created. From the obtained results, it was found that the addition of buckwheat negatively affected the sensory properties of the beer, which was reflected in the negative evaluation of both aroma and taste.
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Dosažitelný stupeň prokvašení ve vztahu k ječmeni
Zárubová, Emílie
In my bachelor thesis on “Achievable degree of fermentation in relation to barley” I am dealing with chapters related to achievable degree of beer fermentation. At the beginning of the work, there are information about spring barley, its history, anatomical structure and chemical composition of the grain. Hereafter, the requirements for malting barley varieties are described and several important varieties are characterized. Very important is the chapter about fermentation, its course and individual types. The core is a chapter on the possibilities of determining fermentability and the factors that affect it. Furthermore, the theme of Czech beer is processed, including the requirements for beer to be included under the CHZO Czech beer. The work also includes chapters on beer production, partial stages of production, as well as raw materials needed for beer production.
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Výroba piva s CHZO "České pivo" a piva vyráběného v EU
Dolníčková, Tamara
The aim of my bachelor thesis is to describe issues regarding the process of beer production in the Czech Republic - starting with the characteristics of individual raw materials that are needed for brewing (barley and malt associated therewith, hops, water and yeast), then further characterize the all operations that take place in the brewery (mashing, wort boiling, fermentation, filtration and pasteurization of beer), describe and define the protected geographical indication "Czech beer", to name and describe varieties of barley, which is preferred for Czech beer and explain how our beer differs from beers produced in the European Union, or which specific species are preferred in the country and in foreign countries.
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Czech breweries a their cartelisation 1869-1918
Rozinková, Kateřina ; Jakubec, Ivan (referee) ; Jančík, Drahomír (referee)
This thesis aims to capture the fundamental factors of development of Czech breweries and their cartelization in period 1869 - 1918. It analyzes three big companies, which represent specific ways of organization. It analyzes especially the mechanisms of their business and financial results, technological level, organization of sales and cooperation in cartels. Cartels are discussed separately and mentioned is their importance for the development of the field in the period.
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