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Comparison of nutritional and utility value of tubers in selected cultivars of table potatoes
BOUŠKOVÁ, Jana
The aim of this bachelor thesis was to evaluate the differences in the content of selected nutritionally significant substances and evaluation of cooking quality for the selected set of varieties of consumer potatoes. A general introduction to the issue is contained in the literary overview. In 2019, a small-scale experiment was established in Lukavci with 6 varieties of consumer potato varieties and 1 variety for processing into starch (as a contrast control). Cultivation took place under the conditions of conventional cultivation technology. The crop was harvested by hand on 11. 10. 2019. Subsequently, samples were taken for chemical analysis. The experiment evaluated the average tuber weight, dry matter content, N-substances and protein content, total polyphenol content and total antioxydant activity. The table value of tubers was assessed through a cooking test with a panel of evaluators. All data obtained were statistically evaluated and processed into graphs.
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Changes of selected indicators during the aging of beer
NOVÁK, Jan
The diploma thesis deals with the monitoring of selected quality parameters of chemical analysis during the beer maturation. The course of the change in alcohol content, the actual and apparent extract in the beer, the extract of the original wort and the degree of fermentation of the beer were monitored. Results of the analysis of beers from the Mini-Brewery of the Faculty of Agriculture of the University of South Bohemia in České Budějovice and the brewery Litovel, a.s. are compared in a uniform technological time of production at the end of maturation just before bottling with samples of beers purchased in the market network in the Czech Republic.
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The issues of proving the use of pesticides in illegal poisoning of animals
Křížová, Iveta ; Cajthaml, Tomáš (advisor) ; Kukla, Jaroslav (referee)
Pesticide poisoning is a worldwide problem. Pesticides are chemicals designed to eliminate unwanted organisms. Many products are banned due to their toxicity, but they are still being abused. The problem arises in proving poisoning due to lack of evidence. Tracing chemicals using chemical attribution signatures is a relatively new method used in forensic sciences, but pesticides are understudied in this field. Characteristic compounds in chemicals are searched for that may provide the necessary information about produce and use illicit substances. This bachelor's thesis deals with the abuse of pesticide products in illegal poisoning of wildlife. Special attention is paid to carbofuran, which is the most frequently abused pesticide in the Czech Republic. The aim of the experimental part was to analyze carbofuran preparations and to prove that individual preparations differ qualitatively from each other.
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Bioflavouring of beer using new Czech hop varieties
Ondruch, Petr ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis focuses on bioflavouring of beer using new czech hop varieties. Dry hopping is a phenomem, that contributes to the attractiveness and diversity of beer and is nowadays gaining in popularity. The aim of this work was to determine the effect of dry hopping on sensory profile and analytical parametrs of dry-hopped beers using czech hop varieties. Sensory evaluation and chemical analysis of these beers were taken. The chemical analysis included determination of the basic beer characteristics, total phenolic a flavonoid content, antioxidant activity and the concentration of selected organic acids and chemical elements. It was found out that dry-hopped beers compared to the reference beer presented higher bitterness, antioxidant activity and contained higher amount of flavonoids. Also an increase in pottasium, manganese, copper, calcium and malic acid levels was reported. The pH of beer samples was not affected by dry hopping. Sensory evaluation showed that dry hopping had a positive influence on the overall enjoyment of the beer, which was mainly determined by the higher aroma and more intense bitterness. By summaring all the data, it is obvious that dry hopping of beer using new czech hop varieties has a positive effect on the quality of the final beer and these hop varities are suitable for further use in the beer industry.
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Chemical composition of photovoltaic panels
Koudelová, Marta ; Šebek, Ondřej (advisor) ; Tejnecký, Václav (referee)
The bachelor's thesis is focused on the issue of photovoltaic cells and panels. The literature search was formed from selected available literature with the purpose to characterize different types of the crystalline silicon photovoltaic cells and thin-films photovoltaic cells and describe the application of photovoltaic cells in the world and in the Czech Republic. In the next part of this thesis is a summary of current knowledge about recycling of photovoltaic cells and other utilization of layers and their possible impact on the environment. The practical part of the thesis deals with selected samples of PV panels. A few samples of photovoltaic panels were taken for chemical analyses. Chemical analyses are performed of the five samples of the photovoltaic panels. The results of chemical analyses were compared with acquired data from the literature. The results of the multielementary analysis of selected samples was that the photovoltaic panels contain a risk elements (e. g. As, Cd, Sb, Mo). The PV panels also contain economics utilizable elements (Ag). Content of silicon is up to 78,18 % SiO2. Key words Photovoltaic panel, photovoltaic cell, chemical analysis, risk elements, recycling
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Analysis of sweet peppers of different geographical origin
Fiala, Petr ; Mikulíková, Renata (referee) ; Diviš, Pavel (advisor)
The diploma thesis is focused on the determination of basic nutritional properties of 26 samples of ground pepper from different countries and evaluates, whether the chemical composition of ground pepper is affected by the geographical origin. The amount of 19 nutritional properties were determined by advanced analytical methodes (ICP-OES, HPLC DAD, HPLC ELSD) together with other laboratory techniques. Final results were statistically processed by the methods of analysis of variance (ANOVA), cluster analysis, principal component analysis (PCA) and discriminant analysis (DA). Statistical evaluation confirmed, that the chemical composition is affected by the geographical origin. Analysis of variance (ANOVA) determined 14 parameters to statistically differ (p
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An analysis of simple carbohydrate content in fruit as a means of data verification for use in clinical practice
Eliášová, Marie ; Starnovská, Tamara (advisor) ; Vyhnánková, Ivana (referee)
Introduction: Nowadays an occurrence of diseases related to carbohydrate metabolism, such as diabetes mellitus, obesity, metabolic syndrome or cardiovascular diseases, is rising. The medical nutrition which is an integral part of the therapy of these diseases includes a recommendation of fruit intake. Nevertheless, this recommendation does not take into account differences in carbohydrate content and composition in various fruit species. The simple carbohydrate intake by patients with the mentioned diseases can have serious medical consequences and therefore, it would be appropriate to make a selection of suitable and unsuitable fruit species based on their carbohydrate content and composition. With such knowledge it would be possible to create or specify recommendations for fruit intake for the mentioned diseases. The data of carbohydrate content and composition in fruit are publicly available in Czech Food Composition Database, nevertheless, these data should not be used to make recommendations until their validity is checked. An independent chemical analysis is an effective tool for verification of the data validity. Objectives: The first objective of this thesis was to perform an independent chemical analysis of various fruit species to characterize their simple carbohydrates and assess,...
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Optimization of chemical analysis of selected components in material of historical artworks
Pekař, Martin ; Čabala, Radomír (advisor) ; Hudeček, Jiří (referee)
The simplification of the historical pieces of work samples' treatment is described in the dissertation. The recent methods have been inappropriate therefore, modification of the treatment was necessary. The dammar and copal resin, important restoration materials, were used in the experiment. HPLC-MS, HPLC-ELSD, GC-FID, GC-MS and pyrolysis GC- MS were applied. The concentration of fatty acids in the historical sculpture was determined by GC-MS, and it was compared to the content of fatty acids inside an egg. For identification of monosaccharide in the gum, GC-MS (hexamethyldisilazan, trimethylchlorsilan, and pyridine) is the suitable method. GC-MS determines the same composition of dammar resin as stated in the cited sources. The simple process for the samples' treatment was designed.
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Chemical composition of photovoltaic panels
Koudelová, Marta ; Šebek, Ondřej (advisor) ; Tejnecký, Václav (referee)
The bachelor's thesis is focused on the issue of photovoltaic cells and panels. The literature search was formed from selected available literature with the purpose to characterize different types of the crystalline silicon photovoltaic cells and thin-films photovoltaic cells and describe the application of photovoltaic cells in the world and in the Czech Republic. In the next part of this thesis is a summary of current knowledge about recycling of photovoltaic cells and other utilization of layers and their possible impact on the environment. The practical part of the thesis deals with selected samples of PV panels. A few samples of photovoltaic panels were taken for chemical analyses. Chemical analyses are performed of the five samples of the photovoltaic panels. The results of chemical analyses were compared with acquired data from the literature. The results of the multielementary analysis of selected samples was that the photovoltaic panels contain a risk elements (e. g. As, Cd, Sb, Mo). The PV panels also contain economics utilizable elements (Ag). Content of silicon is up to 78,18 % SiO2. Key words Photovoltaic panel, photovoltaic cell, chemical analysis, risk elements, recycling
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