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Škůdci rostlin pěstovaných v akvaponii
Božik, Kristián
Aquaponic farms have become known to people in recent years. This is a great way to get plant and animal food in one place. The problem, however, is the fact that even with this way of growing plants, we cannot avoid the presence of diseases, pests or other abiotic disorders that can endanger production. This diploma thesis deals with the possible occurrence of pests and plant diseases that can endanger the function of the farm and possible ways of their protection, with a focus on a biological protection. Due to the presence of fish and bacteria, it is necessary to consider the properties of the active substance, which could have an unintended effect on these non-target organisms. The occurrence of pests was monitored in an experiment in growing lettuce. The occurrence of aphids was observed, and the most suitable method of crop treatment was chosen. The aphid treatment consisted of the application of a rapeseed oil-based preparation.
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Characterization of lipids in cheese analogues
Bittnerová, Eva ; Šimíčková, Adéla (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the identification and quantification of free and bound fatty acids in samples of vegetable oils, specifically in linseed and rapeseed, and in cheese analogues made from them. The theoretical part deals with the characterization of cheese analogues, the composition and technology of fresh cheese production and the description of selected vegetable oils. It also contains the principle and instrumentation of gas chromatography with a flame ionization detector. In the experimental part, model samples of fresh cheese analogues with the addition of linseed and rapeseed oil and the corresponding oil as the basic raw material for their production were analyzed. The fat was extracted from the cheese analogues with a mixture of diethylether and petroleumether, the fatty acids were converted to methylesters by acid esterification with methanolic bortrifluoride catalyst and determined by gas chromatography with flame ionization detection. A total of 15 fatty acids were identified, predominantly oleic, linolenic and palmitic acids. In both oils, oleic, linoleic and linolenic acids were the most represented; significant amounts of myristic, palmitic and stearic acids were also found in the analog samples. The content of free fatty acids was significantly lower than that bound of all samples.
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Dielectric Properties of Vegetable Oils for Electrical Engineering
Spohner, Milan ; Mejzlík,, Miroslav (referee) ; Mentlík, Václav (referee) ; Liedermann, Karel (advisor)
The dissertation thesis deals with the analysis of prospective environmentally compatible electrical insulating fluids for electrical engineering in relation to their chemical structure. The thesis starts with the overview of the current state of the art and of the latest trends in the use of synthetic and biodegradable natural oils. In the experimental part were studied these oils: mineral oils, rapeseed oil, sunflower oils, soybean oil, methyl oleate, peanut oil, MCT oil, castor oil and other. Dielectric properties were measured using LRC meter Agilent 4980A including dielectric liquid test fixture Agilent 16452A and also by the Novocontrol Alpha-A analyzer. Electrical properties are presented in the frequency range 10 mHz – 1 MHz range in the temperature interval 253 K to 363 K. The work goes on with the study of the suitability of individual oils for lower temperature, including the impact of the chemical structure and formulation on electrical properties.
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Characterization of lipids in cheese analogues
Bittnerová, Eva ; Šimíčková, Adéla (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the identification and quantification of free and bound fatty acids in samples of vegetable oils, specifically in linseed and rapeseed, and in cheese analogues made from them. The theoretical part deals with the characterization of cheese analogues, the composition and technology of fresh cheese production and the description of selected vegetable oils. It also contains the principle and instrumentation of gas chromatography with a flame ionization detector. In the experimental part, model samples of fresh cheese analogues with the addition of linseed and rapeseed oil and the corresponding oil as the basic raw material for their production were analyzed. The fat was extracted from the cheese analogues with a mixture of diethylether and petroleumether, the fatty acids were converted to methylesters by acid esterification with methanolic bortrifluoride catalyst and determined by gas chromatography with flame ionization detection. A total of 15 fatty acids were identified, predominantly oleic, linolenic and palmitic acids. In both oils, oleic, linoleic and linolenic acids were the most represented; significant amounts of myristic, palmitic and stearic acids were also found in the analog samples. The content of free fatty acids was significantly lower than that bound of all samples.
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Dielectric Properties of Vegetable Oils for Electrical Engineering
Spohner, Milan ; Mejzlík,, Miroslav (referee) ; Mentlík, Václav (referee) ; Liedermann, Karel (advisor)
The dissertation thesis deals with the analysis of prospective environmentally compatible electrical insulating fluids for electrical engineering in relation to their chemical structure. The thesis starts with the overview of the current state of the art and of the latest trends in the use of synthetic and biodegradable natural oils. In the experimental part were studied these oils: mineral oils, rapeseed oil, sunflower oils, soybean oil, methyl oleate, peanut oil, MCT oil, castor oil and other. Dielectric properties were measured using LRC meter Agilent 4980A including dielectric liquid test fixture Agilent 16452A and also by the Novocontrol Alpha-A analyzer. Electrical properties are presented in the frequency range 10 mHz – 1 MHz range in the temperature interval 253 K to 363 K. The work goes on with the study of the suitability of individual oils for lower temperature, including the impact of the chemical structure and formulation on electrical properties.
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Effect of linoleic and α-linolenic acidis in pig nutrition on quantity and quality of intramuscular fat of pork with emphasis on the n-6/n-3 PUFA-spectrum
Vehovský, Karel ; Stupka, Roman (advisor)
Human nutrition is a function of nutrients' intake from food. The essential nutrients needed by the human body to produce energy, growth and repair of cells, tissues and organs and which accepts in the human diet, are fats. They are obtained from plant or animal sources. Especially animal fats are often ranged among the unpopular food components. Czech Republic is a country with traditionally high consumption of pork. Recently, about healthy foods greatly increase the interest. These include some animal products having an altered composition of fatty acids in fats. The content and composition of saturated and unsaturated fatty acids in human nutrition are important for protecting of human health. The high content of saturated fatty acids in foods and unfavorable ratio between the n-6 and n-3 fatty acids may be the cause of many diseases, especially cardiovascular diseases. Fats in the diet should contain saturated, monounsaturated and polyunsaturated fatty acids, in a ratio of about 1: 1.4: 0,6. From a health perspective, the most important are the n-3 polyunsaturated fatty acids. Animal fats, however, contain sufficient n-6 polyunsaturated fatty acids, n-3, however, a little. Pork meat quality from the viewpoint of fatty acids composition is currently not very favorable. Significant effects on the fatty acids profile of animal fats have the fats in the feed. It is thus the possibility of by using the diet to influence the composition of fatty acids in the fat in pig. The work is focused on the possibility of influencing the fatty acids composition of pork intramuscular fat using supplementation of different sources and different feeding techniques of unsaturated fatty acids in the feed in pigs. In the experiment, as a source of unsaturated fatty acids the supplement of the rapeseed or soybean oil was used. The results demonstrate that the above unsaturated fatty acid sources significantly changes the fatty acid composition of intramuscular fat.
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Impact of alternative feed on growth, yield and sensory evaluation of flesh of salmonids.
PFLUG, Róbert
The bachelor thesis evaluates the impact of alternative feed on growth, yield and sensory evaluation of flesh of salmonids. The technology "finishing feeding" and its impact on these indicators was evaluated by a feeding test conducted in trout farm in Annin (Klatovské rybářství a.s.). The experimental species was brook trout (Salvelinus fontinalis L.) with average weight of 156 ? 4,91 g. The test was carried out for 135 days and there were 2 diets. Diet A (rapeseed oil, RO) or B (fish oil, FO) or their combination (45RO:90FO; 90RO:45FO). Each treatment was carried out in duplicate. After 45, 90 days and at the end of the test, evaluation of production characteristics, yield and sensory evulation of fish muscle was carried out. Fish oil replacement by rapeseed oil had no effects on fish survival, growth, feed conversion and yield. After 45 days (first sensory evoluation), flesh of fish fed diet with rapeseed oil was better senzory evaluated than fish fed fish oil diet. However, the later sensory evaluation didn?t show any statistical differences among the treatments.
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Effect of alternative feed on content of omega 3 fatty acids in fish muscles
KREJSA, Jakub
The aim of my bachelor thesis was to evaluate the effect of fish oil substitution for rapeseed oil in the feed on the fat content and fatty acid composition in the flesh of Brook trout (Salvelinus fontinalis) in the finishing feeding technology. The experiment was conducted in 2012 for the period of 135 days. The individuals of Brook trout were divided into four groups. The first two groups were fed with the feed containing only rapeseed or fish oil. The feeding of the remaining two groups was divided into two phases. In the first phase the fish oil was partly replaced by the rapeseed oil. In the second phase the fish oil was replaced by the feed which contained fish oil only. It was proved that a half replacement of the fish oil with the rapeseed oil does not influence the content of fat in the flesh of Brook trout. We observed that the fish had the higher content of MUFA and n-6 PUFA and lower content of n-3 PUFA, DHA, EPA and n-3/n-6 with increasing period where the feed with rapeseed oil was served. Following application of the finishing feeding technology with the use of feed with fish oil had the opposite effects. Furthermore, the dilution model was proved to be highly reliable for the prediction of the fatty acids composition. Based on these findings, it is possible to predict changes of fatty acid composition in the flesh of Brook trout as well as to predict how long is needed to apply finishing feeding to reach required content of EPA+DHA or n-3 HUFA.
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PROSPECTUS
Hellerová, Hana ; Hartman, Ladislav (advisor) ; Potoček, Jaroslav (referee)
Ve své práci, jak již název napovídá, se zabývám využitím řepkového oleje jako alternativního paliva na místo nafty. Díky vyčerpatelnému zdroji: ropy, ze které se nafta vyrábí, je toto téma v dnešní době velice diskutované, prozatím jsou s ním malé zkušenosti, avšak do budoucna je jednou z mála variant náhrady fosilních paliv. Z tohoto důvodu aplikuji šetření do praxe, provádím výzkum ve skutečně existující společnosti, která denně provozuje několik mechanizačních strojů poháněných litry a litry nafty a zkoumám ekonomický dopad na náklady při nahrazení nafty alternativní pohonnou hmotou - řepkovým olejem. Pro větší zajímavost volím výrobu vlastního filtrovaného oleje z nakoupeného řepkového semene, na novém lisovacím zařízení, to vše mimo jiné za pomoci dohledu zaměstnanců na chod strojů.
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