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Pretreatment of hops for further processing in beer technology
Tichá, Anna ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis deals with pre-treatment of hops for further processing in beer technology. In the experimental part of the work, the effect of low temperatures, as pre-treatment of hops, on the monitored parameters was observed. Three types of cold pretreatment were used. In two cases, the hop material was frozen using a freezer at -25 ° C and in the second case at -70 ° C. In the third case, the hop material was treated by contact with liquid nitrogen in combination with mechanical treatment. The variety of hop materiál was Žatecký poloraný červeňák, which were in the form of pellets or pressed hop cones. The total bitterness of the samples, the total content of phenolic substances, the total content of flavonoids, the antioxidant activity and the concentration of essential oils, specifically myrcene humulene and geraniol, were examined. The effect of pre-treatment was investigated during conventional worth boiling as well as dryhopping. The experimental part includes descriptions of the hopping process, descriptions of individual analytical methods. A parallel measurement was performed on each sample. Significant advantages or disadvantages of some of the pretreatments were not demonstrable, however, the most significant differences were observed in samples hopped with hops pretreated by freezing at -70 ° C, which had a positive effect on the amount of extracted essential oils during cold hops.
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Historical brewery - potential for regional development
Mosler, Štěpán ; Boháč, Ivo (referee) ; Králová, Eva (referee) ; Zemánková, Helena (advisor)
Nowadays there are hundreds of breweries scattered throughout Bohemia, Moravia and Silesia, waiting for their new future. They are either abandoned or in private property. In the worst case they have been deteriorating with no hope of recovery. There are not many left. It is very difficult to find a new function and especially enlightened investor. Important thing is how we will treat with these structures in the future. Will we use this unique potential, or leave this place for a new function? Which way we can choose? What is the potential of these buildings and what they need? This thesis attempts to briefly describe and demonstrate the value of brewery architecture which due to dramatic changes in society became endangered. And to offer possible solutions for the preservation this unique buildings their charm and atmosphere for the next generations.
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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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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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Vliv technologie pěstování chmele (Humulus lupulus L.) na kvalitu produktu a využití produktu
KLÍMA, Tomáš
The thesis is focused on the technology of hop growing and the quality of the product of hops, i.e., hop cones. The theoretical part of the thesis defines the hop plant in general and varieties produces in the Czech Republic. It also deals with protection against insect and diseases, fertilization of hops and the technology used in cultivation. Finally, the theoretical part deals with the processing of the hop product. In the practical part, the thesis establishes generally valid rules in hop cul-tivation technology. The effect of NanoFYT Si, which contains SiO2 particles, is then tested in a field experiment. This experiment is then evaluated and discussed with previous research on the effect of silicon on field crops.
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Vývoj a rozmístění pěstování a produkce chmele ve světě
PAVLIŠOVÁ, Aneta
The bachelor thesis deals with the distribution of hops production and areas of hop fields according to the countries of the world and with the distribution of area of hop fields according to small districts of the Czech Republic. It also monitors the development of these distributions. In the introductory chapters of the thesis the hop literature and characteristics of hop as agricultural crop is given. Data for analyses comes from databases of the Food and Agriculture Organization - FAO (for countries) and the Czech land office (statistics for small districts), and they are transformed into resume tables, graphs and maps. In the long term, the largest hops producers in the world are the USA and Germany, with a considerable distance from the Czech Republic and China and, with a further distance from Poland and Slovenia. The number of hop countries is gradually decreasing and hops production is increasingly concentrated into the USA and Germany. The Czech Republic has the largest areas of hop fields in the Rakovník, Louny, Žatec and Podbořany small districts. The area of hop fields has decreased significantly in the Czech Republic.
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Raw materials for beer production - history and present and their benefits for human health
NOHEJL, Vlastimil
This bachelor's thesis outlines the evolution of brewing from its outset to the present time. The aspects of production, processing, division, and composition of raw brewing materials are described in detail as well as the possibility of using alternative plant components to create non-traditional beers. The next chapter outlines the process of beer production with the emphasis on the individual technological operations and the importance of mashing temperatures. Since beer is a natural, nutritionally rich, fermented beverage, the final part of the thesis examines its health benefits.
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Comparison of selected parameters of draft beers and lagers from breweries and microbrewery
HEJTMÁNKOVÁ, Zdeňka
The dissertation compares selected qualitative parameters beers on tap and lagers produced in large breweries and mini-breweries. The first part of the thesis briefly describes the basic raw materials for beer production. This is followed by a description of the production technology,which includes the production of malt and wort, fermentation and the finishing of beer. The practical part of the dissertation describes selected types of beer. Values obtained from a component analysis of beers are evaluated in tables and graphs. Individual beers are assessed mainly according to the alcohol content (% vol.). The difference between the microbrewery and large breweries was insignificant. The work includes sensory evaluation of selected samples. Taste, aroma, opacity, carbonation and bitterness of beers are assessed. The best rated beer in the sensory rating was Samson BOCK. From the mini-brewery Čtyrák 12 ° light premium lager beer was the best.
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Vacuolar proteins in development of yeast colonies
Trubitsyna, Yana ; Palková, Zdena (advisor) ; Heidingsfeld, Olga (referee)
The laboratory strains of yeast Saccharomyces Cerevisiae form colonies which can differentiate into two main cell subpopulations. U and L cells demonstrate different morphology, metabolism and stress-resistance. It was also proved that some of metabolic pathways in U cells are a similar to ones in tumor cells. The unique metabolism is activated in U cells; the TORC1 is active in these cells together with autophagy and glycogen accumulation, which are characteristic for cells with inactivated TORC1. CORVET and HOPS complexes together with vacuolar ATPase are involved in processes related to vacuolar fusion and trafficking. Also, these complexes contribute to the regulation of TORC1 activity. Vam6p is a subunit of HOPS complex and it is also involved in regulation of TORC1 acting as GEF for Gtr1p GTPase, which activates TORC1. The aim of this study was to outline whether selected subunits of mentioned complexes affect TORC1 activity in U cells. Further aim was to confirm the effect of Vam6p on selected proteins production. These proteins were chosen based on results of proteomic analysis performed in our laboratory. In order to investigate possible effects of proteins of interest absence on colonies' morphology, strains deleted in selected genes were prepared (VPS3, VPS8, VPS33, VPS41, VPH2, VAC7 a...
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Pretreatment of hops for further processing in beer technology
Tichá, Anna ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis deals with pre-treatment of hops for further processing in beer technology. In the experimental part of the work, the effect of low temperatures, as pre-treatment of hops, on the monitored parameters was observed. Three types of cold pretreatment were used. In two cases, the hop material was frozen using a freezer at -25 ° C and in the second case at -70 ° C. In the third case, the hop material was treated by contact with liquid nitrogen in combination with mechanical treatment. The variety of hop materiál was Žatecký poloraný červeňák, which were in the form of pellets or pressed hop cones. The total bitterness of the samples, the total content of phenolic substances, the total content of flavonoids, the antioxidant activity and the concentration of essential oils, specifically myrcene humulene and geraniol, were examined. The effect of pre-treatment was investigated during conventional worth boiling as well as dryhopping. The experimental part includes descriptions of the hopping process, descriptions of individual analytical methods. A parallel measurement was performed on each sample. Significant advantages or disadvantages of some of the pretreatments were not demonstrable, however, the most significant differences were observed in samples hopped with hops pretreated by freezing at -70 ° C, which had a positive effect on the amount of extracted essential oils during cold hops.
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