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Burning pellets from non-wood biomass in boilers II
Linda, Matúš ; Baláš, Marek (referee) ; Zejda, Vojtěch (advisor)
Bachelor thesis is divided into four main chapters. The first chapter deals with issue of combustion of agropellets in boilers. This section specifies types of pellets, their production and problems of combustion in boilers associated with formation of emissions. The second chapter specifies valid legislation and emissions limits. The third chapter describes fuel analysis of agropellets samples. This includes an analysis in order to determine the properties and chemical composition of agropellets resulting in determination of gross heat and calorific value. The fourth chapter evaluates agropellets influence on boilers and emissions creation on the basis of data and knowledge. The results are compared with data of other commonly used solid fuel found in literature sources.
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Selected nutritional parameters of some lesser known fruit
Diblíková, Michaela ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
Diploma thesis is focused on the chemical analysis of the juices of black, red and white currant and jostaberry (Ribes a Ribes x culverwellii). The theoretical part is focused to the definition of fruit, fruit importance in human nutrition, description of Ribes and Ribes x culverwellii genuses, active substances in the currants and the jostaberry, description of selected chemical parameters and the determination of some of them. The procedures of determining for the following chemical parameters are described in the experimental section: determination of reducing sugars, determination of total and soluble solids, formol number, pH, titratable acidity, determination of total phenols and anthocyanins and determination of vitamin C in two samples jostaberry, six varieties of black currants, one variety of white currant and two varieties of red currants. Based on the evaluation of the obtained results, the comparison was made with different varieties and the thesis that "overall comparison of the different varieties in the content of phenolic compounds, vitamin C and anthocyanins appears to be the most promising variety of blackcurrant demon. It should however be noted that the highest content of phenolics and anthocyanins were determined in jostaberry„ has been suggested.
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Basic characterization of selected samples of animal feeds
Svoboda, Ilona ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
The aim of the diploma thesis was to choose poper parameters for a quick and simple characterization of animal feed, to verify working procedures and to apply these on chosen samples. Within the scope of this work, samples of animal dog feed produced in a private company „Adamkovy tlacenky“ were analyzed. The feed is in the form of brawn, stored in artificial casing; it consists of up to 80% of animal components and up to 20% of vegetable components, while the rest of the weight is the pork gelatine. The feed does not contain preservatives, colourings as well as any other chemically produced additives. For the analysis three formulas were chosen: "Hovězinka", "Kuřátko" and "Srdcovka", the composition of which is protected by the patent. The choice was made to include samples of different composition. The content of raw crude protein, fat, fibre, dry basis, and ash was determined. The obtained values were compared with the standards for feed normally utilized by the feed industry. The results will be used to improve the formulas and to develop new types of feed.
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The assessment of basic chemical parameters of natural cheese
Školová, Dominika ; Babák, Libor (referee) ; Vítová, Eva (advisor)
The aim of this work was to determine basic chemical parameters of natural cheese, namely Camembert type (white mold cheese) and Emmentaler type (cheese with high-heat curd). Model samples of cheese were produced in a pilot plant using unpasteurized milk in"organic" quality. Based on the literature search following parameters suitable for simple and fast characterization of cheese composition were selected: dry matter (drying to constant weight), fat in dry matter (calculated), total nitrogen (resp. determination of protein content) by the Kjeldahl method and fats, resp. total lipids (extraction with solvent). The results were finally compared with samples of the corresponding cheese type purchased on the market.
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The addition of carbon dioxide to milk for cheese production
Králová, Petra ; Hrstka, Miroslav (referee) ; Kvasnička, Miloš (advisor)
This work deals with the addition of carbon dioxide to milk for cheese production. The first aim was to elaborate a literary search focused on chemical composition of milk and its changes after addition of carbon dioxide and to describe production processes, with or without addition of carbon dioxide. The opening part was in particular focused on production of cheese with carbon dioxide and what all this gas causes during production. Carbon dioxide significantly decreases pH, thereby preventing from multiplication of undesirable microorganisms, it is also very important for shortening of production time, because it shortens the coagulation time. The main aim of experimental part was to determine the optimum addition of carbon dioxide to milk for production of Balkan cheese and using several analytical methods to compare cheese produced with and without addition of carbon dioxide. The sensory methods suitable for following of sensory differences of produced cheeses were also chosen and applied. By request of Dairy in Polná Ltd., the operation economy was calculated, which revealed that production with carbon dioxide is very useful and can reduce production costs of Balkan cheese, which would certainly be positive. The advantages and disadvantages of cheese production with carbon dioxide for consumers as well as for producer are evaluated as conclusion of this work.
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Study of fruit ripening and storage
Langová, Jiřina ; Zemanová, Jana (referee) ; Babák, Libor (advisor)
There are many changes in fruit quality during its ripening and storage. The following four apple varieties were studied: Champion, Glostr, Golden Delicious and Idaret. Amount of reducing sugars, total amount of sugars, quantities of acids, refractive solids and loss of starch were monitored. The changes of parameters, the differences between the varieties and differences in storage were compared. Parameters were monitored from mid-August 2008, when the apples ripened. After the harvest, apples were stored in a cool box at 2 - 3 ° C and at room temperature 20 - 23 ° C. Apples stored in the cool box were analyzed till the end of March 2009, and apples stored at room temperature until the beginning of January 2009. Total quantity of sugars in all varieties increases before harvest, while it decreases after picking the apples. The quantity of reducing sugars in apples rises gradually and after their picking it falls significantly in apples stored at 20 - 23 ° C. In apples stored in the cool box it continues rising until the end of November, and then it also decreases. Losses of starch are considerable and they are accelerated after the harvest. The quantity of acids also decreases throughout and amounts of refractive solids increases. For all varieties there are significant changes in storage at 20 - 23 ° C. Temperature, therefore, significantly affects processing of sugars and acids in fruit respiration.
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Basic chemical characteristics of chokeberry juices
Zámorská, Vendula ; Veselá, Mária (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals wirh characteristics of berries and assessment of basic chemical parameters of chokeberry juices (Aronia melanocarpa). The theoretical part is about the basic botanical description of selected varieties of Aronia and its taxonomic status. The following are important substances contained in fruits and their part in human nutrition and use for food purposes. The end of the theoretical part of bachelor thesis is about basic methods of determining the nutritional parameters of berries. In the experimental part solids content of the fruit. Furthermore soluble dry matter content, pH, titratable acidity, formol number, reducing sacharides and ascorbic acid by spectrofotometry were determined. Based on the results, juices were compared.
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Basic chemical characteristics of juices from selected red currants varieties
Rucká, Markéta ; Jurečková, Zuzana (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis is focused on the determination of basic chemical characteristics of selected red currants varieties from the Research and Breeding Institute of Pomology Holovousy Ltd. The theoretical part concentrates on general information about red currant, such as history of cultivation, origin and its expansion. There is also mention of the general characteristics of currant, currant building and significance of red currant cultivation. Chapter "Individual varieties" deals with the analysed varieties of red currants, especially its description and its biological properties, followed by an overview of the main substances contained in red currants and their brief description. Bachelor thesis also presents examples of the processing and the utilization of red currant in the food industry. The final chapter provides information about the individual determinations of the chemical characteristics of red currants, which include juice yield, soluble solids content, total dry matter content, pH, titratable acidity, formol number and reducing sugars. The experimental part describes the specific conditions and methods of individual determinations, followed by a summary of the results and their discussion. Variety Jesan showed the highest juice yield (63 ml per 100 g) and the highest pH value (3,16). The highest soluble solids content (13,94 %) and the highest formol number (22,83 ml of 0,1 M NaOH per 100 g) was determined in a variety Jonkheer van Tets. The highest dry matter value was detected for variety Rovada (14,48 %). The titratable acids content was highest in variety NŠLS 11/6 (403,88 mmol•kg-1). The highest concentration of reducing sugars was found in variety Tatran (8,17 %).
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Basic chemical characteristics of juices of selected white currant varieties
Zlámalová, Petra ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
The bachelor thesis deals with determination of basic chemical charcteristics of juices of selected white currant varieties. The theoretical part focuses on botanical description of the plant, history of cultivation, important chemical substances contained in the fruits and their effects on human body. There is also described use of white currant in the food industry and the basic principals of determination of the juice parameters, there. The experimental part focuses on determination of juice yield, soluble solids, pH, dry matter content, titrable acidity and formol number. Based on resultes, the individual cultivars were compared. The determination showes that cultivar Olin has the highest titrable acidity and the most of soluble solids at all. Cultivar Orion has the biggest juice yield, cultivar Primus has the biggest dry matter content and cultivar Jantar has the highest formol number and pH.
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Basic chemical characteristics of juices from selected blackcurrant varieties
Maňásková, Eva ; Pořízka, Jaromír (referee) ; Vespalcová, Milena (advisor)
This thesis deals with the basic characteristic of juices of the selected varieties of blackcurrant. The theoretical part presents the history and origin of this fruit cultivation, basic botanical description of each species and selected varieties and also features active substances contained in fruits. Conclusion the theoretical part then describes procedures basic methods of determining the various chemical parameters of fruits. In the experimental part was set tentative determination juice yield, soluble solids content, pH, titratable acidity and formol number. Based on the results were different varieties compared.
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