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Alcohol-free beers with herbal extracts
Vyskočilová, Terezie ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
This bachelor thesis deals with alcohol-free beers and herbal extracts, which are the beers flavoured with. In the theoretical part the methods of non-alcoholic beer production and the representation of the active ingredients in herbs are described. A total of 7 herbal extracts were prepared and added into 3 non-alcoholic Czech beers. Each variant was examined in order to detect changes of the content of active substances before and after the addition of the herbal extract. The content of polyphenols, flavonoids, bitter substances and iso-bitter acids as well as antioxidant activity were analyzed spectrophotometrically. Using HPLC/UV-VIS analysis a content of catechins was assayed. The two selected flavours were encapsulated into liposome; the particles were tested of size and stability. Sensory analysis of all herbal extracts including the encapsulated ones was performed to determine the response of consumers and flavour preferences.
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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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Bioflavouring of low alcoholic beer by dry hopping
Dušánek, Václav ; Mikulíková, Renata (referee) ; Pořízka, Jaromír (advisor)
This bachelor thesis deals with the influence of cold hopping of low-alcohol beers on analytical properties and sensory profile of beer. The effect of cold hopping was observed using the varieties Kazbek, Jazz, Mimosa and Uran. In the experimental part, the production process of low-alcohol beer using immobilized yeast is described. After the main fermentation, the low-alcohol beer was kegged into five cuvettes and after 20 days cold-hopped at a dose of 3 g/l with individual varieties. The effect of cold hopping with individual varieties on the organoleptic properties of the beer was observed. Bitterness was determined, with cold-hopped beers showing an increase between 17-24 % in bitterness. Furthermore, the ethanol content was determined by high-performance liquid chromatography at 2,14 % vol. A significant increase in all volatiles, in particular -myrcene and linalool, was found in the cold-hopped beers by gas chromatography with mass spectrometry. The sensory analysis showed that the cold hopping had a positive effect on the overall impression and masked the taste defects of the reference low-alcohol beer. The best hop evaluated for the use of the cold hopping method was the Kazbek variety. The Jazz and Mimosa varieties were also perceived relatively positively by the evaluators. On the other hand, the Uran variety achieved a worse overall impression than the reference beer.
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Možnosti výroby nealkoholického piva
Krčálová, Jana
This work (bachelor degree) deals with the ways how to produce nonalcoholic beer. The ingrediences and production itself are included as well. The most used ways are three. The direct production, the microorganism application and the alcohol removal. All of them show advantages and disadvantages that are presented. The market survey was performed as well to prove the possible differences between alcoholic and nonalcoholic beer prices. For that reason, this work is broaden concerning market research and its price policy results.
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Vliv kombinace sladů a vybraných látek na finální kvalitu nízkostupňového piva
Caltová, Jana
The theme of this thesis is. The effect of storage and other elements on beer quality. The theoretical part of my work concentrates on the history and production of beer, methods of production of low-alcohol and non-alcoholic beer. In my thesis I deal with reverse osmosis, use of special kinds of yeasts or with fermentation. In the practical part of my work is described the production of low-alcohol and non-alcoholic beer. For non-alcoholic beers there were used different kinds of storages. The practical part of my work is focused on results of sensory analysis and measurement analysis.
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Technologie výroby nízkostupňových piv
Jedličková, Nikola
The theme of this thesis is "Production technology of low beers." In the introduction to the theoretical part defines the notion of low-alcohol and non-alcoholic beer. Furthermore, the introduction of work focuses on the technology of classic beer. Then describes the variol possibilities for the preparation of low beers, which can be divided into three groups -- to limit the formation of alkohol in beer production, the use of special yeast species and microorganism and elimination of alkohol from the finished beer. The practical part contains the production of low burs with different kinds of the hops. Subsequently were performedanalytical measurements and sensory with evaluation results of the analysis.
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Alcohol-free beers with herbal extracts
Vyskočilová, Terezie ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
This bachelor thesis deals with alcohol-free beers and herbal extracts, which are the beers flavoured with. In the theoretical part the methods of non-alcoholic beer production and the representation of the active ingredients in herbs are described. A total of 7 herbal extracts were prepared and added into 3 non-alcoholic Czech beers. Each variant was examined in order to detect changes of the content of active substances before and after the addition of the herbal extract. The content of polyphenols, flavonoids, bitter substances and iso-bitter acids as well as antioxidant activity were analyzed spectrophotometrically. Using HPLC/UV-VIS analysis a content of catechins was assayed. The two selected flavours were encapsulated into liposome; the particles were tested of size and stability. Sensory analysis of all herbal extracts including the encapsulated ones was performed to determine the response of consumers and flavour preferences.
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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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Sensory analysis of non-alcoholic beers depending on production technology
BRABCOVÁ, Markéta
The aim of this dissertation was sensorial evaluation of non-alcoholic beers according technology of their production. Ten samples of non-alcoholic beers from different breweries were tested with sensorial analysis. Non-alcoholic beer Lobkowitz Premium and Radegast Birell were made with help of special types of yeasts. The rest of non-alcoholic beers was made by technology of controlled fermentation. Non-alcoholic beer Samson made by method of controlled fermentation gained the first place and Radegast Birell made with help of special types of yeasts gained the second place. It is not possible to specify, which one from used technologies of producing non-alcoholic beers have got a proven positive effect on the sensorial quality of beer, from identified data. Sample D (Samson) reached maximum values of complex perception of aroma, fullness, briskness and character of bitterness in sensorial evaluation of chosen criterions. The highest value of complex perception of taste was recorded at sample J (Radegast Birell). On the other hand, sample F (Budweiser Budvar) reached the lowest values of fullness, briskness and komplex perception of taste. The lowest values of komplex perception of aroma was noted in sample G (Dudák) and sample C (Bernard) had got the lowest values in complex perception of character of bitterness. Samples B (Platan) and D (Samson) contained additional sweetener E 954 (Saccharin). Saccharin is weaker than standard sugar but it leaves a bitter taste behind after ingestion. Men perceived sample B (Platan) in terms of aroma and taste negatively and in term of character of bitterness positively. Women registered only minimal differences in perception of aroma, intensity of taste and character of bitterness in this sample. Used sweetener could inluenced men´s view on taste because of its bitterness. The conducted survey also showed that in situations where the respondents can not give alcoholic beer , 80 % of men´s surveyed by opting for non-alcoholic beer . On the contrary, 87 % of women would prefer a different soft drink.
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