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Proposal of systems for targeted transoprt of compounds of sweet taste
Demová, Radoslava ; Hlaváček, Viliam (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on possibility of immobilization sweeteners on polymeric system. In the theoretical part information about sweeteners, carrier systems and the possibility of immobilization technique were reviewed. In the experimental part preparation of nanoparticles of polyhydroxybutyrate (PHB) was optimized. The PHB particles were characterized by dynamic light scattering (DLS). PHB particles were activated by plasma treatment. The surface morphology was studied using infrared and Raman spectroscopy. Immobilization of following substances with a sweet taste was tested: glucose, fructose, sucrose, mannitol, sorbitol and erythritol. From these compounds only sucrose was immobilized on PHB particles successfully. Prepared immobilized particles were exposed to the artificial stomach juice, intestinal juices and bile acids and amount of released sucrose was monitored. Finally, long-term stability prepared particles was measured and also the amount of sucrose released was determined.
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Study of thermal properties of sucrose
Pecháčková, Kateřina ; Lucie, Trhlíková (referee) ; Zmeškal, Oldřich (advisor)
This work is focused on the study of thermal properties of materials that are used for accumulating heat on the basis of phase transition. These are mainly sugar alcohols (mannitol, erythritol) or carbohydrates (glucose) respectively. Thermal properties, thermal in particular, and thermal conductivity and specific heat capacity were measured in a wide range of temperatures comprising of the transformation from the solid to the liquid phase in the entire volume of substance. To study the temperature dependence of thermal properties, transient methods were used, that allow to determine the diffusion and relaxation time, thermal absorption coefficient and a parameter characterizing the properties of resources based on the fractal model of heat transfer (shape and the heating of the sample). Thermal parameters were determined from those values for defined ideal heat source (planar) and defined ideal heating (leap). There are results of three sucrose samples produced in the Opava refinery (unrefined, refined, clean). Differences in their thermal properties were studied. In addition, thermal properties of a pure solution (commercial) of sugar in distilled water at different concentrations were studied (1:1, 3:1, 1:3). The results presented in this thesis may be used to more efficient use of thermal energy in heating of dwellings, both with the use of solutions, which have a higher heat capacity than water and also with the use of phase transformation.
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Influence of selected coffee bean roasting technology on its chemical composition
Šajdlerová, Kristýna ; Mikulíková, Renata (referee) ; Diviš, Pavel (advisor)
The subject of this diploma thesis is the monitoring of chemical changes taking place in the coffee bean during roasting using various devices. For these purposes an industrial coffee roaster and a home roaster were used in the practical part. The theoretical part deals mainly with the characterization of coffee beans in terms of the content of various compounds and a description of the changes that occur during roasting. Different types of roasting machines are also presented. In the experimental part the roasting of coffee beans and the determination of the concentration of selected substances in the samples taken during roasting were performed. The monitored parameters included the concentration of sucrose, organic acids (citric, acetic, lactic, malic, formic and chlorogenic), caffeine and aromatic substances. One of the biggest differences found between the both roasters is the reduction in the concentration of chlorogenic acid, which decreased by 33 % for domestic equipment, while the decrease was almost doubled for industrial roasters. Another significant difference was also observed in the change in sucrose content. Sucrose degradation occurred in 94 % of coffee bean samples roasted on an industrial roaster, while only 75 % of the second type of roaster.
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Solid form of liposomal systems for inhalation
Fardová, Lucie ; Kalina, Michal (referee) ; Mravec, Filip (advisor)
This thesis deals with the preparation of solid liposomal systems for inhalation delivery. Liposomal systems were prepared by rehydration of a phospholipid film from dipalmitoylphosphatidylcholine. A sucrose solution used for film rehydration served as a protectant during spray drying. Additional liposome samples contained cholesterol, phosphatidic acid, or polyethylene glycol for better stabilization. The prepared liposome solutions were examined using scanning transmission electron microscopy, dynamic light scattering, and electrophoretic light scattering methods. Dried powders were measured using infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and determination of particle aerodynamic size. The results demonstrate the successful preparation of all liposomal systems, their drying into powder form, and subsequent reconstruction after rehydration with water or buffer. Based on the observed properties, liposomes with polyethylene glycol appeared to be the most suitable.
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Influence of selected coffee bean roasting technology on its chemical composition
Šajdlerová, Kristýna ; Mikulíková, Renata (referee) ; Diviš, Pavel (advisor)
The subject of this diploma thesis is the monitoring of chemical changes taking place in the coffee bean during roasting using various devices. For these purposes an industrial coffee roaster and a home roaster were used in the practical part. The theoretical part deals mainly with the characterization of coffee beans in terms of the content of various compounds and a description of the changes that occur during roasting. Different types of roasting machines are also presented. In the experimental part the roasting of coffee beans and the determination of the concentration of selected substances in the samples taken during roasting were performed. The monitored parameters included the concentration of sucrose, organic acids (citric, acetic, lactic, malic, formic and chlorogenic), caffeine and aromatic substances. One of the biggest differences found between the both roasters is the reduction in the concentration of chlorogenic acid, which decreased by 33 % for domestic equipment, while the decrease was almost doubled for industrial roasters. Another significant difference was also observed in the change in sucrose content. Sucrose degradation occurred in 94 % of coffee bean samples roasted on an industrial roaster, while only 75 % of the second type of roaster.
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Nutrigenomic analysis of diet influence in prenatal and early development on metabolic syndrome aspects manifestation in adulthood.
Školníková, Elena ; Šeda, Ondřej (advisor) ; Černá, Marie (referee) ; Malínská, Hana (referee)
16 Abstract The rising prevalence in noncommunicable diseases worldwide calls for the effort to determine their underlying causes. Common metabolic disorders in particular overwhelm the healthcare systems and are a one of the leading causes of poor quality of life of patients. Metabolic syndrome is represented by concurrence of several conditions - dyslipidaemia, obesity, hypertension or impaired glucose tolerance - altered metabolic phenotypes related to genetic and environmental factors. Recent studies suggest that early-life exposure to certain environmental stimuli is particularly capable of changing the mammalian phenotypes. Nutrition, as one of the major factors influencing health, is naturally a focus of research, which studies the link between parental diets and phenotypic alterations in offspring. The developmental origins of health and disease were historically more focused on maternal undernutrition, it is, however, more important to focus on surplus of macronutrients considering the westernization of modern diets. We propose the relevancy of not only the amount of macronutrients in maternal diet, but also their sources, as they may increase disease risk in offspring. Here we report, that sucrose as an alternative carbohydrate in maternal diet, has a marked impact on metabolism of the offspring...
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Regulácia vyrastania kotylárnych pupeňov hrachu
Kucsera, Attila
This work was aimed to achieve more details in regulation of cotyledonary bud outgrowth of pea plants (Pisum sativum L.). Plants were studied after decapitation of the apex and removal of cotyledons and their subsequent substitution with agar gels containing different susbstances. Experiments were perform in light and dark conditions. The obtained results proved that auxin could regulate outgrowth of pea cotyledonary buds. Furthermore, sucrose showed partly inhibitory effect on bud outgrowth. This inhibitory effect was pronounced if plants were cultivated in dark. Next experiments showed that cotyledons could regulate apical dominance depending on light or dark conditions.
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Význam sacharózy ve výrobě a zpracování potravin
Kalábová, Vendula
The Bachelor’s thesis summarises the problems of the importance and use of saccharose. The work mentions the characteristics and the division of saccharides where saccharose falls. It focuses on saccharose as such, its chemical composition and biological, physical, chemical and technological qualities. The work describes naturally occurring saccharose, its products and their use, or more precisely artificially produced saccharose and its use. Its use is mostly specified in food industry as well as its impact on human organism and the resulting dietary recommendations. Last but not least, the work also provides information on the development of sugar consumption both in the Czech Republic and in the world.
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Content of mono and disaccharides in soft drinks and their health impact.
Haurová, Anna ; Hrnčířová, Dana (advisor) ; Dlouhý, Pavel (referee)
Carbohydrates are an integral part of human diet. We distinguish them according to their length, usability, glycemic respond and taste. Sugars are mainly found in sweetened beverages and processed food. Consuming empty calories in the form of sugar sweetened drinks leads to the recommended daily allowance of sugars and total energy intake is being exceeded. It has negative impact on risk of civilization diseases like obesity, type 2 diabetes mellitus, dental carries and depression. Limiting the intake of sweetened beverages and industrial processed foods, principles of healthy diet and enough of exercise helps to prevent these diseases.
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Effect of used sweeteners on sensory properties of fruit jams
PIHLÍK, Pavel
This thesis deals with the sorting and use of sweeteners in the production of fruit spreads. The theoretical part focuses on the sorting of sweetening agents and their classification. Furthermore, it presents procedures of production of fruit spreads and their assortment. The main goal is to compare sensory attributes of jams that I produced according to an assigned recipe, which is described in the practical part of this thesis. These jams were made from regional fruits (strawberries, apricots, sour-cherries) and sweetened with both natural (sucrose, sorbitol, Steviol glycosides) and artificial (sucralose) sweetening agents. The control group of this research were the students and employees of the University of South Bohemia in České Budějovice in the age of 24-60 years. The evaluators filled in a sequence test protocol and a questionnaire for consumers. The results of the sensory analysis were processed into tables and graphs with the aid of statistical methods.
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