|
|
Mycotoxins in Brewing Materials and Beer
Běláková, Sylvie ; Vávrová, Milada (referee) ; Márová, Ivana (referee) ; Kráčmar, Stanislav (referee) ; Čáslavský, Josef (advisor)
The presented thesis deals with the issue of mycotoxins in brewing materials and beer. Attention was devoted mainly to the selected fusarium mycotoxins (deoxynivalenol, zearalenol, T-2 toxin, and HT-2 toxin) ochratoxin A and aflatoxins B1, B2, G1, and G2. The aim of the thesis was to optimize and validate analytical methods for the determination of the above mentioned mycotoxins in the brewing materials and beer. Analytes were separated using high-performance liquid chromatography with mass – spectrometric detection (HPLC-MS/MS) and ultra-performance liquid chromatography with fluorescence detection (UPLC/FLR). These analytical methods were then applied for mapping the occurrence of fusarium mycotoxins in malting barley crops in the Czech Republic and monitoring the level of contamination with mycotoxins in malting and brewing industries. In addition, experiments studying over-foaming of beer were conducted as primary gushing – over-foaming of beer – is connected, similarly as mycotoxins, with the presence of microscopic filamentous fungi in the raw materials for beer production. Studies describing in detail these methods are part of this thesis (Annex I – V). From all published results, it is evident that the occurrence of mycotoxins in cereals including barley is natural and cannot be completely prevented, not even if all conditions of correct agricultural practice are observed. It is known that some mycotoxins present in contaminated malting barley pass to the final product – beer due to their chemical and physical properties. However, the mycotoxin concentrations found do not mean any significant health risk for consumers.
|
|
|
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.
|
|
|
Senzorické vlastnosti sladiny
Piechová, Hana
Beer foaminess is one of the main sensory properties of beer. Polypeptides have a positive effect on foam formation, while lipids have a negative effect. The wort contains both types of substances, but it does not foam by itself due to a lack of carbon dioxide. The aim of the thesis is to find out whether there is any influence of a particular variety and year on the foaminess of the wort. 14 varieties of spring malting barley were monitored at nine locations from the harvest between the years 2020 and 2022. The foaming of the wort was measured on a 1-CUBE type FA device at the Research Institute of Brewing and Malting (Výzkumný ústav pivovarský a sladařský, a. s.). The found foaminess values of the wort were clearly influenced by 30% by year and by 33% by variety. What is statistically significant is that the lowest foaming rate of the varieties was found in the 2020 harvest. The average stability of the wort foaming was 170 s and for individual varieties it ranged from 111–220 s. The statistically significantly lowest foaming stability of the wort was observed in the Overture and KWS Amadora varieties, the highest values of the wort foaming were found in the LG Ester and Spitfire varieties. The KWS Amadora variety showed the greatest foaming variability (70%), the LG Stamgast showed the lowest variability (18.5%). The foaminess of the wort can potentially predict the foaminess of beer.
|
|
|
Možnosti využití sladu pro sportovní výživu
Mišúnová, Lucie
The diploma thesis on “Possibilities of using malts for sports nutrition“is focused on the production of malts and their use in sports supplements. The theoretical part is devoted to individual cereals and pseudocereals, their nutritional composition, individual nutri-ents and their importance in nutrition and some possible products for sports nutrition. The practical part includes the production of single malts from selected cereals and pseudocereals and the production of experimental products that could have applications in sports nutrition. The products were then analysed for sensory analysis and nutritional value was determined.
|
|
|
Vliv technologického postupu na kvalitu sladové whisky
Havlát, Petr
This thesis discusses the specifications of Scotch malt whisky and Irish malt whiskey. It also focuses on various technological aspects of malt whiskey. Specifically malt production, technological possibilities of preparing malt mash, technological influence of fermented malt mash, conditions and processes during maturation and analyzing samples from 100 years old malt whiskey found at the South Pole. The practical part includes the production of malt from the Malz variety of malting barley, from which samples of distillates were subsequently produced under different conditions of sweet mash fermentation and matured for 12 months in laboratory conditions. The distillate samples were mixed according to the type of preparation of the fermented malt mash and diluted to 36 %, 40 %, 44 % and 48 % alcohol by volume. The alcoholic strength varied according to the amount of distillers' yeast added and the length of fermentation. During the practical part, several methods were used to determine the moisture of malting barley, and the starch content in malting barley. Density, alcohol concentration and real alcohol yield were determined psychometrically. Individual samples of the whiskey were GC analyzed after 12 months, revealing a concentration of higher alcohols and several different esters. The CG values were then statistically compared with sensory analysis results which were also statistically evaluated and discussed. The aim of this work was to verify the influence of different technological procedures in the preparation of ripe mash. Apart from dilution, all other technological processes remained the same. Four samples of different alcoholic strengths were created and analysed, one year apart, for the concentration of sensory compounds that carry both positive and negative character in the whisky. The physico-chemical analysis was to be compared with the sensory analysis. The samples were malted in the school's micro malt for pilsner malt. The best sensorial-rated whiskey sample was 44 % alcohol by volume, but this was not statistically confirmed.
|
|
|
Brewing beer in home conditions
Potoček, Petr ; Skryja, Pavel (referee) ; Kilkovský, Bohuslav (advisor)
The thesis compares the conditions of home and industrial beer production. The introduction familiarizes the reader with basic concepts and the process of beer production. The next section compares the brewing methods of infusion and decoction. The final part of the thesis processes the data collected and proposes changes to the procedure of beer brewing at the Faculty of Mechanical Engineering of Brno University of Technology.
|
|
|
Lipid and fatty acid content depending on the barley variety
Havlíková, Michaela ; Pernica,, Marek (referee) ; Svoboda, Zdeněk (advisor)
The bachelor thesis deals with the evaluation of the influence of barley variety on lipid content and fatty acid profile. Samples of barley and malt from the 2022 harvest, seven varieties recommended by Research Institute of Brewing and Malting, Plc. for the production of beer with the protected geographical indication ,,České pivo“, were analysed. The theoretical part of the thesis characterizes lipids and fatty acids, describes their occurrence and importance in barley grain, describes the changes associated with them during the technology of malt and beer production and how these changes can affect the final quality of beer. The possibilities for the determination of lipids and fatty acids are given and attention is paid to the determination of the fatty acid profile by using the method of gas chromatography. In the experimental part, lipids were extracted from barley grains and malt by fluidized bed extraction method using the fexIKA® dive-in control extractor. The extracted lipids were transesterified into methyl esters of the corresponding fatty acids, which were analysed by gas chromatography with flame ionization detection on a SLB-IL 100 capillary column. In both barley and malt were identified eight fatty acids as their methyl esters. The predominant fatty acid was linoleic acid. Reduction of total lipid content and change in fatty acid profile due to the malting process were observed.
|
|
|
Technológia výroby ovocných pív
Seriš, Daniel
This bachelor thesis deals with the description of the production technology of fruit beers. The literary part is devoted to the history of beer production, the characteristics of the basic raw materials, the technological process of production, the assortment and the legislative requirements for quality. Increased attention is laid on the fruit component its uses and its application into the beer during its production. In the practical part, 8 samples of fruit beers were analyzed. 4 samples were experimentally prepared in the Institute of Harvesting Technology of Horticultural Products Faculty of Horticulture at Mendel University in Brno and the remaining 4 were purchased in commercial chains and breweries. In the laboratory, ethanol, polyphenols and antioxidant capacity were determined in samples. By sensory analysis the organoleptic qualities of beers were evaluated. The flavor, smell, color, fruity taste, bitterness and overall impression were evaluated. The results were statistically evaluated and processed into graphs and tables.
|
|
|
Sledování vybraných parametrů ovlivňujících gushing u sladovnického ječmene
Němec, David
Presented diploma thesis is about malting barley as a initial ingredient for producing beer and about its negative effect called gushing. In the first part of dissertation is described technological procedure of malt production and defined term gushing. Also there are mentioned information about cause of initiation, reduction possibilities and methods to describe gushing phenomena. Practical part is mainly focused to define susceptibility of malting barley to gushing and for testing was chosen three days test Carlsberg. The gushing was monitored on differently treated vegetation of spring barley which was grown in seasons 2012 and 2013 in Hrubčice locality. On the performed 160 testing samples were evaluated influence of threads barley on degree of barley gushing.
|
|
|
Možnosti ovlivnění kvality sladu a jeho uplatnění ve výrobě piva
Podaný, Adam
In the literary part of the thesis are information about the possibilities of influencing the quality of malt and its application in the beer production. In the practical part we explored the effect of nitrogen and sulphur on quality of malt. The results of small-plot field trials established on plots of the Agrospol agricultural enterprise in 2012 in Velká Bystřic we can see the positive effect of applied N and S fertilizers on the quality of the malt produced from the grain of spring barley variety Bojos. Nitrogen and sulfur fertilization improved grain germination. The grain of the variant fertilized with N and N + S - fertilizers had faster germination. Sulfate sulfur increased the starch content in the grain. The amount of extract in malt corresponded with the starch content in barley grain. Also content of the proteins is corresponded with doses of the nitrogen fertilizers.
|
guest ::
