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Characterization of minor fruit varieties in terms of use in the food industry
Jurečková, Zuzana ; Vítová, Eva (referee) ; Golian, Jozef (referee) ; Diviš, Pavel (advisor)
The thesis deals with one group of small fruits, the genus Ribes, ie currants, and gooseberries. It assesses their physical and chemical parameters with respect to the possibility of use in these properties for the design of a new type of product – beverages. Titration, spectrometric and other methods were used for the evaluation of these properties. A total of fifteen of these methods were available (total juice yield, juice pH, total dry matter, soluble fruit dry matter, titratable acidity, formolic number, reducing carbohydrate content, D-glucose, D-fructose and sucrose content, total polyphenolic substance content, anthocyanins, vitamin C and total antioxidant capacity) and a total of nine analytes (copper, iron, magnesium, phosphorus, zinc, manganese, potassium, calcium and sodium) were selected for the determination of mineral elements. For two years (harvest 2014 and 2015), these parameters were monitored for color variants of currants (white, red and black) and gooseberries (green-fruited, yellow-fruited and red-fruited). A total of six white varieties were tested in the group of currants - Olin, Jantar, Primus, Blanka, Viktoria and Orion, eleven varieties of red currants - Junnifer, Jesan, Detvan, Rovada, Rubigo, J.V.Tets, Tatran, Losan, Kozolupský raný, Stanca, NŠLS 11/6 and eleven varieties of black currant varieties - Ometa, Démon, Triton, Ben Hope, Ruben, Ben Gairm, Ben Lomond, Moravia, Ben Conan, Fokus and Ceres. A total of five varieties of green-fruited gooseberries were tested - Zebín, Mucurines, Rixanta, Rodnik and Prima. Yellow-fruited gooseberries were available in four varieties - Lemon Giant, Invicta, Golden Fig and Darek. The red-fruited gooseberries included varieties - Rolonda, Alan, Karat, Karmen, Krasnoslawjanskij, Himnomacki Rot, Remarka, Tamara and Black Neguš. Using Tukey's test, an analysis was performed and by scoring individual varieties based on the results of individual analyzes, a list of recommended varieties was compiled for further work on the development of a new beverage. Unfortunately, in 2015 there were very few fruits of green-fruited and yellow-fruited gooseberries, so it was decided that the volume of fruit will fall on the testing of bioactive substances. Therefore, at the end of the work, it is not possible to objectively evaluate these varieties of gooseberries in the whole range of analyzes. Therefore, the point evaluation of varieties was based on the averages of individual varieties. The red-fruited varieties were available in full, and therefore a full evaluation could take place. The most significant differences between red gooseberry varieties were in the content of bioactive substances (the content of polyphenolic substances, anthocyanin dyes, and vitamin C) and antioxidant capacity. These results were provided to the food subject, which continued to work with these values. Based on this project, utility model No. PUV 2016-33171 and the resulting combined drink based on wine and fruit juice were developed.
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Economic aspects use of energy of photovoltaic plant
Cerman, Marek ; Procházka, Jiří (referee) ; Macháček, Jan (advisor)
The major topic of this master‘s thesis is to create a complex model of general photovoltaic power plant (PVP). First chapters are engaged in research of photovoltaic. Growth of globally installed power and analysis of situation in Czech Republic are described in this section. The spectrum of conditions is introduced, from current legislative framework up to local Sun radiation. The actual technologies and their advantages are depicted, especially rate of utilization of energy. Expected trends of future development of conversion efficiency are mentioned, with prediction of production costs of photovoltaic. In context with those aspects, the question of grid parity achievement arises. The own assembled model of photovoltaic power plant has been created in Microsoft Excel. The mathematical apparatus is described in a separate chapter, individually solving technical part, which main result – the amount of yearly generated electricity, is applied for economical calculation. Final results are the usual economic indicators, mainly: Net Present Value (NPV), Internal Rate of Return (IRR), Levelized Cost of Electricity (LCOE). There is series of aspects defined by user in the model which may impact the amount of produced electricity and economics of user’s project, such as use of loan, replacement of converters, operational costs etc. These aspects are frequently neglected by project sellers. In the end, intended photovoltaic power plants of 2.75 kWp and 28.98 kWp are simulated by the model in real conditions of 2013. Sensitivity of impact of both proposals to the aspects mentioned above has been analyzed. In the conclusion the achieved results are summarized and the key factors which determine the PVP’s economic efficiency are assessed.
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Recovery of the method for assessment of fatty acids
Gross, Michal ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
The objective of this bachelor thesis is to verify recovery yield used for determination of fatty acids based on gas chromatography with flame-ionization detection. In the theoretical part, fatty acids and lipids are characterized and extraction of lipidic fraction from food samples with its subsequent adjustments is suggested. Furthermore, the principle and current instrumentation of capillary gas chromatography with flame-ionization detection and standard parameters for validation of the analytical method are specified. In the experimental part, verification of recovery yield of the method for assessment of fatty acids was performed. The used method includes extraction of lipids from a sample in accordance with the standard ISO 1735 regulation and transesterification of both free and bounded fatty acids catalysed by boron trifluoride according to the ISO 12966-2 standard regulation. The produced methyl esters can be effectively determined using gas chromatography with flame-ionization detector. Analysed samples of rapeseed oil and tilsiter-type cheese were purchased in a common food market.
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Basic chemical characteristics of cranberry juice
Cao, Ha Thuy ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis is about lingonberries and cranberries. It is mainly about berries which were used for chemical analysis. The berries are from the Research and Breeding Institute of Pomology Holovousy Ltd. and they have delivered six cultivars of lingonberries and three cultivars of cranberries. There is a research of general information about classification, botanical description, important chemical substances such as vitamins, natural colorants and products made in the industry. Furthermore there is descriprion of chemical methods for basic analysis. The next part of bachelor thesis is about how all these methods were applied to berry juice. What instruments and chemicals were used. First assessment was profit of juice which was about 50,00–60,00 %, but lingonberry Runo bilawskie has at least 31,49 % and cranberries have less profit too. Total solids were determined in the range of 11,40 % (Pilgrim) to 18,50 % (Runo bielawskie) and solitable solids are in range of 10,00 % (Pilgrim) to 16,08 % (Korál). Lingonberry contains more reducing sugars (8,81–12,92 %) than cranberry (7,90–9,03 %). Titratable acids are about 32,04–49,60 mmol.l-1 for lingonberry and about 55,40–60,67 mmol.l-1 for cranberry. The measurements show that pH of both berries are about 3. The most phenolic substances are found in range of 2187,11–3476,75 mg.l-1. Berries content anthocyans colorants in range of 54,91-65,29 mg.l-1 and the most in cranberry. All results are shown in charts and in the end there is a discussion and conclusion about methods and results.
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Increasing the Yield of BGA Repair Process
Janíček, Martin ; Vala, Radek (referee) ; Řihák, Pavel (advisor)
This thesis deals with possibilities of increasing the yield of BGA repair process. First there is mentioned basic problematics and its notions, problems and possibilities. Next it deals with technological aspects of repairing of devices in BGA covers. Also there is mentioned basic problematics of evaluating of yield. There is stated current state of solving the problem and also there is suggested new design of application which would be more optimal for evaluation of the yield of process. This thesis contains results of practical testing of methods of application of flux affecting final quality of solder joints as well as kind of flux which was used. At the end
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Analysis of selected milk quality indicators and their impact on the yield and sensory properties of fresh cheeses
PLONER, Michaela
The aim of the diploma thesis was to evaluate the effect of cow´s milk quality on the fermentation, yield and selected properties of fresh cheese produced in laboratory conditions. For this purpose, there were 51 fresh cheese samples produced in three trials from 17 bulk milk samples originating from six farms. For milk and cheese sam-ples, selected analyzes were performed, and the obtained data were statistically eval-uated. The chemical composition, physicochemical and sensory properties, weight and yield of fresh cheese were evaluated depending on i) the time of fermentation, ii) the milk quality. As expected, the average values of pH, weight and yield of the fresh cheeses differed during the fermentation. The protein content, lactose and so-matic cell counts significantly influenced the yield and quality indicators of fresh cheese. The quality of milk also influenced the assessment of sensory properties, es-pecially color intensity and consistency. To achieve the optimal pH of fresh cheese (<5.00), the time of fermentation should be from 15 to 16 hours.
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Základy užitkového chovu poštovních holubů a jejich etologie
PITZMOS, Jiří
The bachelor's thesis deals with the basics of commercial breeding of carrier pigeons and their ethology. The aim of this thesis is to determine the economic intensity of closed intensive breeding of medium size pigeons and to evaluate the factors influencing profitability. Part of the research is a breeding experiment in which utility and production parameters such as nesting frequency, hatchability, daily pigeon gains, yield in relation to food intake and ethological monitoring are monitored.
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Characterization of minor fruit varieties in terms of use in the food industry
Jurečková, Zuzana ; Vítová, Eva (referee) ; Golian, Jozef (referee) ; Diviš, Pavel (advisor)
The thesis deals with one group of small fruits, the genus Ribes, ie currants, and gooseberries. It assesses their physical and chemical parameters with respect to the possibility of use in these properties for the design of a new type of product – beverages. Titration, spectrometric and other methods were used for the evaluation of these properties. A total of fifteen of these methods were available (total juice yield, juice pH, total dry matter, soluble fruit dry matter, titratable acidity, formolic number, reducing carbohydrate content, D-glucose, D-fructose and sucrose content, total polyphenolic substance content, anthocyanins, vitamin C and total antioxidant capacity) and a total of nine analytes (copper, iron, magnesium, phosphorus, zinc, manganese, potassium, calcium and sodium) were selected for the determination of mineral elements. For two years (harvest 2014 and 2015), these parameters were monitored for color variants of currants (white, red and black) and gooseberries (green-fruited, yellow-fruited and red-fruited). A total of six white varieties were tested in the group of currants - Olin, Jantar, Primus, Blanka, Viktoria and Orion, eleven varieties of red currants - Junnifer, Jesan, Detvan, Rovada, Rubigo, J.V.Tets, Tatran, Losan, Kozolupský raný, Stanca, NŠLS 11/6 and eleven varieties of black currant varieties - Ometa, Démon, Triton, Ben Hope, Ruben, Ben Gairm, Ben Lomond, Moravia, Ben Conan, Fokus and Ceres. A total of five varieties of green-fruited gooseberries were tested - Zebín, Mucurines, Rixanta, Rodnik and Prima. Yellow-fruited gooseberries were available in four varieties - Lemon Giant, Invicta, Golden Fig and Darek. The red-fruited gooseberries included varieties - Rolonda, Alan, Karat, Karmen, Krasnoslawjanskij, Himnomacki Rot, Remarka, Tamara and Black Neguš. Using Tukey's test, an analysis was performed and by scoring individual varieties based on the results of individual analyzes, a list of recommended varieties was compiled for further work on the development of a new beverage. Unfortunately, in 2015 there were very few fruits of green-fruited and yellow-fruited gooseberries, so it was decided that the volume of fruit will fall on the testing of bioactive substances. Therefore, at the end of the work, it is not possible to objectively evaluate these varieties of gooseberries in the whole range of analyzes. Therefore, the point evaluation of varieties was based on the averages of individual varieties. The red-fruited varieties were available in full, and therefore a full evaluation could take place. The most significant differences between red gooseberry varieties were in the content of bioactive substances (the content of polyphenolic substances, anthocyanin dyes, and vitamin C) and antioxidant capacity. These results were provided to the food subject, which continued to work with these values. Based on this project, utility model No. PUV 2016-33171 and the resulting combined drink based on wine and fruit juice were developed.
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Vliv ročního období na tržní produkci sýrárny zpracovávající kravské mléko
Doleželová, Petra
In this graduation thesis, I have investigated the influence of the season on market production dairies. he aim of the work is divided into the following sub-goals: the influence of season on the reception of milk to the dairy, protein content in milk, yield milk and ferment aktivity. The dairy, which I described handles mainly on cow's milk for cheese Niva, curd and cream. Milk came from 8 surrounding farms, which breeding only the Czech Pied cattle. Monitoring was carried out for a period of one year starting from November 2014 to October 2015. I found that most milk was bought from suppliers in summer and least in the winter months. The milk protein content was highest in winter and lowest in summer. While the amount of milk purchased was constant, the price per liter of milk has a tendency of decreasing (from CZK 9.05 to 7.48), and thus the costs of buying milk lower, while revenues are constant. Milk yield ranged from 7.43 liters of milk / kg of cheese (in October) to 8.42 l / kg cheese (in February).
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Recovery of the method for assessment of fatty acids
Gross, Michal ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
The objective of this bachelor thesis is to verify recovery yield used for determination of fatty acids based on gas chromatography with flame-ionization detection. In the theoretical part, fatty acids and lipids are characterized and extraction of lipidic fraction from food samples with its subsequent adjustments is suggested. Furthermore, the principle and current instrumentation of capillary gas chromatography with flame-ionization detection and standard parameters for validation of the analytical method are specified. In the experimental part, verification of recovery yield of the method for assessment of fatty acids was performed. The used method includes extraction of lipids from a sample in accordance with the standard ISO 1735 regulation and transesterification of both free and bounded fatty acids catalysed by boron trifluoride according to the ISO 12966-2 standard regulation. The produced methyl esters can be effectively determined using gas chromatography with flame-ionization detector. Analysed samples of rapeseed oil and tilsiter-type cheese were purchased in a common food market.
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