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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.
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Optimalization of SPME for assessment of volatile sulphur compounds in malt and beer
Mišovie, Zuzana ; Vespalcová, Milena (referee) ; Mikulíková, Renata (advisor)
Volatile sulphur substances originating during technological processes in malt and beer production can be a cause of various off-flavors and aromas. Their precursors are sulphur-containing amino acids. Sulphur substances play an important role in brewing as even in very low concentrations they can negatively affect total character of beer. Therefore, it is necessary to monitor volatile sulphur substances and their precursors to eliminate undesirable processes. Because sulphur substances occur in beer and raw materials at trace levels, microanalytical methods are used for their detection. This diploma thesis describes the problems of sulphur substances and their determination using the SPME/GC method.
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Introducing of method of pyridoxine determination by liquid chromatography in food products and resources
Nechyba, Ondřej ; Benešová, Karolína (referee) ; Vespalcová, Milena (advisor)
This master‘s thesis deals with quantification of vitamin B6 in beverages, food supplements and raw materials in food industry. The literature retrieval part summarizes general information about vitamines, vitamine B6, nicotine acid and vitamine B1. Further on in this part there is described principle of high pressure liquid chromatography and quantification of individual vitamines. In the experimental there are listed used tools, apparatus and chemicals. There is described preparation of idividual samples of food supplements, energy drinks, multivitamine drinks, beers and brewer’s malts. This chapter also contains information about chromatographic separatory systems Shimadzu and SpectraSystem. The quantification was performed by high pressure liquid chromatography on a reverse phase with gradient elution and two ways of detection, fluorescent and spectrofotmetric. The result of experimental activities and vitamine content in analysed samples are presented in the next chapter. In the final contains summarization of results obtained in experimental part. The maser’s thesis was measured in the laboratory of Institute of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology.
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HPLC determination of thiamine in barley, malt and food supplements
Vítková, Kateřina ; Běláková, Sylva (referee) ; Vespalcová, Milena (advisor)
The aim of this diploma thesis is focused on determination of B vitamin in food especially in malting barley and malt. This diploma thesis is consists of theoretical and experimental parts including the conclusion and supplements. Theoretical part describes thiamine characteristic, chemical structure, chemical and physical properties, function of thiamin in organism, impact it´s insufficiency to the human health, occurrence in common food and methods for it´s determination. Further are describing theoretical principles of high-efficiency liquid chromatography, chromatography on reverse phase, derivatization and ways of validation. In the Experimental section is detailed description of used method for determination of thiamine in barley and malt, fresh mash and beer but also in common food supplements as are B-kompex, Pangamin and Thiamin. Determination was made by high-efficiency liquid chromatography on reverse phase with isocratic elution and fluorescent detection. Next part introduce the results of theses, discussion of experimental work, volume of thiamine in analyzed food and validation parameters of used method. In the conclusion are valorized results of experimental work. In the attachment are graphs of standard curves, chromatogram and calculations of validation parameters. Diploma thesis was realized in laboratory of Chemistry and Technology of Foodstuff, Faculty of chemistry, Brno University of Technology.
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Determination of beta-carotene in barleycorn by HPLC
Puč, Vojtěch ; Maleček, Miroslav (referee) ; Prýma, Jaroslav (advisor)
This diploma thesis deals with the natural antioxidants present in cereals, especially in barley (Hordeum vulgare). A close attention is paid to the study of carotenoids determination was conducted. In the experimental part, the method of beta-carotene determination was optimized using high-performance liquid chromatography, diode array detector and mass detector (HPLC/DAD/APCI-MS). The method was used for the beta-carotene and lutein determination in the samples of barleycorn, malt and green barley. This method involves the sample saponification, extraction by diethylether, followed by separation on ODS Hypersil 250x4,6 mm, 5m column, using MTBE/MeOH (20:80) as mobile phase and spectrophotometric detection (450 nm). Quantitative analysis was implemented in the HPLC/DAD system. The MS detector was used for identification of analytes. A number of still unpublished data about the content of beta-carotene and lutein in several varieties of malting barley, malt and green barley are stated in this thesis. The highest content of beta-carotene was found in the green barley sample of variety Malz, harvested in first grow phase (8,49 mg/kg of the dry matter). The content of beta-carotene in barleycorn is relatively low (0,07-0,14 mg/kg of the dry matter). The content of beta-carotene is several times higher in the malt produced from barleycorn (0,24-0,56 mg/kg of the dry matter). The diploma thesis was implemented in the Research Institute of Brewing and Malting, Plc. in Brno.
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Determination of zearalenone in malting barley
Wawroszová, Simona ; Čumová,, Martina (referee) ; Běláková, Sylvie (advisor)
This bachelor thesis deals with monitoring of zearalenone content in malting barley using immunochemical method ELISA and consequently method of liquid chromatography with mass spectrometry (LC-MS/MS). Theoretical part describes the brewing raw materials and important toxinogenic filamentous fungi. Special attention was drawn to selected fusarium mycotoxins (fumonisins, trichothecenes, zearalenone). It also describes some methods for determination of mycotoxins. Experimental section describes analyze 90 samples of malting barley of different varieties using method ELISA. In 19 samples zearalenone concentration was higher than limit of quantification. The highest level of zearalenone concentration (39,2 g•kg-1) contained barley, variety Wintmalt, where corn was used as a fore-crop. The samples were subsequently analyzed by LC-MS/MS. Zearalenone concentration was higher than limit of quantification only in four samples, namely in samples of Blaník, Malz and Wintmalt varieties of barley. Furthermore, the samples of intermediate products of malting process were analyzed by LC-MS/MS. No sample showed level of zearalenone higher than limit of quantification.
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Changeof phenolic acids content during malting of spring barley
Štýblová, Romana ; Janoušková, Eva (referee) ; Běláková, Sylvie (advisor)
This bachelor thesis deals with detection of chosen phenolic acids (sinapic acid, caffeic acid, ferulic acid, syringic acid, p – hydroxybenzoic acid, vanillic acid and p – coumaric acid) in the malting barley and monitoring of their changes during making a malt in real enviroment of floor malt house. Tehoretical part describes individual phenolic acids, their presentation in raw material for making of malt and methods for determination . There is described technology of making a malt. The nine samples was taken in experimental part. There were a malting barley, intermediate products of malting, malt and rootlets. Phenolic acids were extracted by alkaline and acid hydrolysis. This samples were detected by Ultra high – performance liquid chromatography using of UV detection (UPLC/PDA).
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Spiral conveyor
Nekoksa, Pavel ; Kašpárek, Jaroslav (referee) ; Malášek, Jiří (advisor)
This bachelor thesis deals with the design and construction design spiral conveyor. In the text part is performed design calculation of the major parts of spiral screw conveyor, drive unit design, storage worm screw, strength check of functional parts and an appropriate choice of material transported. Design documentation based on text part and consists of a conveyor assembly drawing, a list of items and drawing worm screw.
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Determination of ergosterol content in brewing materials
Matyáš, Martin ; Ing.Pavla Kožušníková, Ph.D. (referee) ; Benešová, Karolína (advisor)
Presented bachelor’s thesis is focused on determination of ergosterol content in barley and malt. In theoretical part the presence of ergosterol in barley and malt has been elaborated, the purposes of its determination, detailed overview of previously applied methods of extraction from samples of barley and malt as well as other biological materials and methods of quantification. Practical part is focused on optimizing of extraction and determination of ergosterol by high performance liquid chromatography with diode array detection (HPLC – DAD).
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The quality of raw materials for beer production
SOUČEK, Martin
The subject of the thesis "The quality of raw materials for beer production" is a quality brewing ingredients - barley malt, malt, hops, water and brewer's yeast. Individual ingredients are generally characterized. The main part of the thesis deals with the assessment of quality of raw materials according to various criteria such as the genetic basis, agroecological factors, and technological requirements. The paper also discusses the methods of measurement quality.
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