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Quantification of food waste in municipal waste and the possibility of processing this waste
Orságová, Marie ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
The theoretical study of anaerobic digestion is designed to predict the amount of biogas in food waste. The theoretical part characterizes the processing of biodegradable waste as well as the use of biogas and the calculation method for determining biogas production. In the experimental part, the analytical technique of inductively coupled plasma optical emission spectrometry (ICP-OES) was used to determine minerals (K, Ca, P, Mg, Na, Zn, Cu, Fe and Mn) in food waste, as well as elemental analysis for carbon, oxygen, hydrogen and nitrogen determination. This thesis provides a simplified model that predicts the amount of produced biogas and could be used for further feasibility studies, such as bioreactors dimensioning. The method can be used for different starting materials and repeated for other similar applications in an effort to extend anaerobic digestion systems as a source of clean energy.
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Optimization of HPLC-ELSD method for determination of sugars in foods
Laba, Marija ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This master's thesis deals with the optimalization of HPLC-ELSD method for the determination of carbohydrates in food. The theoretical part focuses on the classification and characterization of carbohydrates, the occurrence of carbohydrates in food and their physiological importance. There was targeted mainly glucose, fructose, sucrose and maltose. There is a brief summary of the analytical methods that can be used to determine carbohydrates. Experimental part is based on a literary review. It also deals with high performance liquid chromatography with evaporative light scattering detector. The main content in this part is the optimalization of condition for reliable and rapid separation of the most frequently occurring carbohydrates in foods. The carbohydrates were identified and quantified under optimum condition in real samples specifically in fruit juice, beer, ketchup and red pepper powder. The result is commented in conclusion.
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Characterization of new czech hop varieties
Faruzel, Vojtěch ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
In this thesis the problem of characterization of new Czech hop varieties was investigated. The selected new varieties were Mimosa, Jazz and Blues. Their composition was compared with the widely used varieties Žatecký poloraný červeňák and Kazbek. The content of -bitter acids and -bitter acids, total phenolic content, flavonoid content and antioxidant activity were determined by UV-VIS spectroscopy for all hop varieties. The composition of hop essential oils was estimated by SPME-GC-MS. The diversity of the hop varieties was confirmed from the measured data by statistical analysis. The new varieties showed statistically significant differences in all monitored parameters, especially in comparison with the varieties Žatecký poloraný červeňák and Kazbek. The quantitatively different representation of -bitter acids and -bitter acids has an influence on the character and intensity of bitterness of these hop varieties. The composition of the hop essential oils, the content of phenolic substances, flavonoids and antioxidant activity are reflected in the different organoleptic properties of the hops analysed and of the beer.
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Extraction of anthocyanin pigments from elderberries pomace
Lošková, Tereza ; Pořízka, Jaromír (referee) ; Vespalcová, Milena (advisor)
This Diploma thesis deals with the production of the concentrate from the Elderberry marc extract (Sambucus nigra L.). The basic chemical characteristics in this concentrate were determined. The theoretical part of the thesis deal with the botanic characteristic of the Elderberry and its berries. The characteristic of the phenolic compounds, mainly anhocyanins was summarized. The use of the anthocyanin pigments in the food industry, the possibilities of their extraction and the concentrate production was discussed. Thereafter the methods of the anthocyanin content and the phenolic content determination were described. In the experimental part of study, the production of the anthocyanin rich extract from Elderberry marc was optimized. The extraction of the marc by the 1:1 ethanol/water (V/V) solvent with the ratio marc/solvent 1:2 (w/V) showed the most convenient. The production of the concentrate followed. During the concentration on the rotary evaporator the pigment degradation was investigated. The degradation decreased with the decrease of the temperature. The final concentrate was prepared from the extract on the rotary evaporator by 45 °C for 15 minutes. This product had the 7times lower volume compared to the initial extract. In the final concentrate come of the chemical characteristic were determined. By liquid chromatography (HPLC) the major pigments cyanidin-3-sambubiosid and cyanidin-3-glucosid were determined. Their total content was determined to 34,9 gl-1. The total anthocyanin content was determined by pH differential method to 7,1 gl-1 (expressed as cyanidin-3-glucoside equivalent). The total phenolic content was determined to 27,1 gl-1 (expressed as gallic acid equivalent) by Folin-Ciocalteu method. By electron paramagnetic resonance the increase in antioxidant activity with the increase in concentration was found. Up to 42 aromatic compounds was determined in Elderberry marc, its extract and the final concentrate.
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Influence of the filtration and pasterurization on content of selected vitamins in beer
Šimíčková, Adéla ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
This master thesis focuses on the influence of the filtration and the pasteurization on the content of the selected vitamins in beer. Specifically, the vitamin B2, B3, B6, B9 and B12. The high performance liquid chromatography with diode array detector was used as a separation method for the vitamin content analysis. First this method was optimized and then validated. The data obtained by analyzing 28 beer samples were evaluated using a statistical method – the analysis of variance. This method provided parameters P, F and Fcrit which are important for the assessment of the statistically significant differences between the individual groups of beer . Based on these parameters, a significant effect of the filtration was observed for the vitamin B2 and B3. The filtration has reduced the amount of the vitamin B2 while it increased the concentration of the vitamin B3. The pasteurization had no significant effect on the vitamin content.
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Characterization of different bran species in terms of ferulic acid content
Nábělek, Jakub ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
This bachelor’s thesis works with an alkaline extraction of a ferulic acid from different kinds of cereal bran. Another researched issue was extraction of nutritionally interesting elements extracted from bran and from hydrolysed waste. Those extracts has possible usage as a mineral fertilizer for plants. In the theoretical part, this thesis deals with problematice of cereals, composition and differences in a cereal grain depending on kinds of cereal and an enviromental conditions. Chemical composition of cereal materials, focused on phenolic acids are also described. Another part deals with theoretical background of methods for the extraction of phenolic acids from bran with description of advantages and disadvantages. Methods for alkaline hydrolysis and extraction of minerals from different kind of bran bran are described in experimental part of this work. Sodium hydroxide (0,5 M) was used for the hydrolysis of bran material. For the determination of the yields of ferulic acid, HPLC method with UV/VIS detection at wave-length 330 nm with usage of mobile phase mixture of methanol and 0,5 % solution of formic acid was used. Acidified deionized water was used for the extraction of nutritionally interesting elements from bran and also from the hydrolyzed material. For the determination of the elemental composition of extracts (Cu, Fe, Zn, Mn, P, Ca, K, Mg), ICP-OES method was used. It was found, that differences in wheat bran species in terms of yields of Ferulic acid are satistically important. The biggest yields of ferulic acid was obtained from the sample of spelt. The smallest yields of this acic was obtained from the sample of oat. Content of micro and macro-elements showed statistical important differences in different kinds of bran and their hydrolyzed waste. Most abundand elemets were obtained from rice bran and from spelts hydrolyzate. The smallest abundand elemens were obtaned from oat bran and hydrolyzate.
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Studying the authenticity of coffee of various geographical origins
Flegr, Šimon ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This diploma thesis researches coffee authenticity problematice, mainly focusing on the authenticity of geographic origin. In the theoretical part of this work, botanical classification is described as well as production technology and processes. The work also includes chemical composition of coffee, describing the major components and changes during production phases. It describes major production areas of the world, in terms of general description and brief history. Problematics with coffee fraud and its identification are also described. Theoretical part also includes general geological description of 17 studied coffee growing regions. Experimental part is devoted to trace amount analysis of selected elements and volatile compounds. The element analysis was conducted using mass spectrometry or optical emission spectrometry, volatile compounds were determined using gas chromatography combined with mass spectrometry detection. Results were statistically described and analyzed, resulting in several discrimination models based on geographic origin.
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Influence of the chicken breeding method on the selected chemical constituents of chicken eggs
Michalec, Adam ; Vespalcová, Milena (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis is focused on the analysis of egg yolks and egg whites from chickens raised with different breeding methods in the Czech Republic using three analytical methods. The Kjeldahl method was used to determine the proteins, the Soxhlet method was used to determine the lipids and ICP-OES was used for elemental analysis. The theoretical part describes the history of chicken breeding, marking and distribution of eggs and composition of eggs based on various aspects. The main point was the separation of egg yolk and egg white and the subsequent description on the chemical and physiological level. Principle of used methods is also described. The experimental part deals with the preparation of samples, calibration samples and process analysis. All the results of analysed substances are summarized, statistically evaluated and compared with the other literature. For this analysis were used eleven different types of eggs from the Czech Republic from six different categories.
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Possibility of utilization of solid waste from spent coffee grounds rafination for agricultural purposes
Slavíková, Zuzana ; Vespalcová, Milena (referee) ; Pořízka, Jaromír (advisor)
The main focus of this diploma thesis is the utilization of spent coffee ground (SCG) and its biorefinery products in agriculture primarly as a prospective organic fertilizer. The study verifies an influence of the addition of native SCG as well as its acid hydrolysed, defatted and oxidized forms to experimental clay soil on chemical and physical properties (ph, conductivity and mineral content). Growing experiments were realized by using Lactuca sativa to detect positive or negative effects on growth. Samples of basic soil and soil with the addition of commercial NPK fertilizer served as a reference to measuring data. Measurements showed that addition of SCG and products of its biorefinery to the soil caused a decrease of pH and an increase of conductivity of soil samples. Significant increase of extractable calcium, magnesium, manganese and moderate increase of potassium content was detected. 2 % addition of SCG to soil had no impact on plants growth. The number and visual appearance of lettuces were comparable with plants in basic soil. No seed on acid hydrolysed samples germinated, which was caused by an increase of conductivity and sulphate content in these samples. In defatted and oxidized samples the early germination and the highest number of lettuces was observed. The low content of phosphorus in all soil samples had a great impact on growth rate and visual appearance of cultivated lettuces. In comparison with soil with NPK addition, lettuces in samples with SCG and its form had a pink-grey colour and lower growth.
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Application of analytical techniques and chemometry for authentification of wine
Pořízka, Jaromír ; Karovičová, Jolana (referee) ; Jarošová, Alžběta (referee) ; Diviš, Pavel (advisor)
This PhD. thesis is focused on application of different analytical techniques for determination of elemental composition of Moravian wine combined with analysis of selected polyphenol compounds. Two spectrometric techniques were used for elemental analysis of wine – Mass spectrometry and Optical emission spectrometry with inductively coupled plasma (ICP-MS and ICP-OES). Analysis of organic constituents of wine was evaluated by High performance liquid chromatograph with diode array detector (HPLC-DAD). Data from analysis of wine were used for construction of mathematical models for determining geographical origin of wine and for determining type of varietal wine. Data handling was performed by usage of multivariate statistical methods (cluster analysis, principal component analysis and canonical discriminant analysis). For the discrimination of wine by the geographical origin, two separate models for white and red wine were constructed. Effectiveness of discrimination of Moravian wine (with knowledge about origin) into 4 wine regions was 100 % successful for white wine and 96,43 % for red wine samples. Those models were used for cross validation test of unknown samples with result 95 % successfully classified samples of white wine and 82,15% of red wine. Besides that, mathematical model for discrimination and classification of varietal wine was made. Müller Thurgau, Riesling and Gruner Veltliner were discriminated by the usage of 8 elemental parameters. Discrimination success rate of known samples was evaluated by canonical discriminant analysis with 95,83% of correctly classified known samples and 70,83% of correctly classified unknown varietal wine (cross validation test). In addition to these part of research, impact of different grape production systems on elemental composition of wine and Vitis Vinifera was studied. The core of the study was to find the connections between the type of agriculture and chemical properties of wine and Vitis Vinifera. Two agriculture systems were assessed – Organic agriculture and Integrated pest management. . Results of this study showed that quantity and manner of pesticide application is very important factor affecting the final elemental composition of the grapevine and wine, especially the content of copper, zinc and manganese. That knowledge can be used in the future for creation of classification model of wine according to grape production system. For comparison of radical scavenging activity, electron paramagnetic resonance spectroscopy (EPR) with DPPH method was used. In the case of this study, the influence of vine growing under different farming systems on the total antioxidant activity of wine was found to be insignificant.
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