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Chromatographic determination of simple sugars in selected beverages
Jurečková, Zuzana ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
An important part of the drinks are simple carbohydrates, because this thesis focuses on this issue. The theoretical part describes the characteristics , production , metabolism and the use of simple carbohydrates such as glucose, fructose and sucrose. There is also the definition of drinks and their main divisions . The literature review is based on the experimental part of analyzing selected beverages by high performance liquid chromatography with refractometric detection coupled to columns or alkyl ion-exchange phases. In conclusion, the results were compared to determine and comment . Nowadays the emphasis is on the correct functioning of the digestive tract. An important factor that supports the intestinal microflora is a prebiotic carbohydrate - tagatosa This could become tagatosa whose properties , production, metabolism in the body and any use is also included in the search . In the experimental part is listed possible optimization analysis of samples containing tagatosy on both types of columns in the HPLC system. The result is again commented in conclusion.
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Industrial production of ethanol
Flajs, Roman ; Zichová, Miroslava (referee) ; Omelková, Jiřina (advisor)
This bachelor thesis deals with ethanol production for food and car industry. The aim of this work is to give a summary of different kinds of raw material especially lignocelluloses and microorganisms used for its processing and fermentation. The thesis focuses especially on technological process of ethanol production and the utilization of different materials for fuel production.
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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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Srovnání vývoje a produkce včelstev zimovaných na zásobách z invertního a řepného cukru
Musila, Jan
This thesis is focused on nutrition specifics of honeybee (Apis mellifera) and its ontogenetic stages, particularly on carbohydrates. The effects of sugar beet saccharose and invert syrup made from sugar beet as feeds for winter stores supply on overwintering, bee colony condition in early spring and the consequent honey yield were evaluated. In total, 70 bee colonies were included in the field experiment. The experiment was made on 6 apiaries in 4 locations within the Czech Republic. The thesis deals with particular tasks associated with chemical components which have negative impact on honeybee and which might occur in artificial feeds. It suggests potential solution of their appearance reduction in bee feeds. Problematics of honey adulteration regarding the type of used bee feed are discussed.
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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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Influence of sucrose in culture medium on phosphoenolpyruvate carboxylase activity in tobacco leaves
Fiala, Martin ; Ryšlavá, Helena (advisor) ; Hoffmeisterová, Hana (referee)
Plants are under physiological conditions autotrophic organisms that are capable to fix CO2 for the synthesis of carbohydrates. Metabolism of plants may be affected by presence of sucrose in the culture medium. The aim of this study was to determine whether activity of phosphoenolpyruvate carboxylase (EC 4.1.1.31, PEPC) and nitrate reductase (EC 1.7.1.1, NR) were affected by the presence of sucrose in the culture medium. PEPC plays important role in photosynthesis of C4 and CAM plants; in C3 plants PEPC plays an anaplerotic role by replenishing of citric acid cycle intermediates and providing carbon skeletons to support nitrogen assimilation. PEPC activity in plants grown in culture medium with sucrose was about 70 % higher than in plants grown without sucrose. Level of phosphorylation of PEPC was studied by detemnination of PEPC activity after alkaline phosphatase treatment, activation of PEPC by D-glucose-6-phosphate and inhibition of PEPC by L-malate. PEPC activity after dephosphorylation in both groups of plants was decreased at similar level. Also activation of PEPC by D-glucose-6-phosphate and inhibition of PEPC by L-malate was very similar in plants grown with sucrose and without sucrose. NR is a key enzyme in nitrogen fixation. Activity of NR in plants grown with sucrose was about 90 %...
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Chromatographic determination of simple sugars in selected beverages
Jurečková, Zuzana ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
An important part of the drinks are simple carbohydrates, because this thesis focuses on this issue. The theoretical part describes the characteristics , production , metabolism and the use of simple carbohydrates such as glucose, fructose and sucrose. There is also the definition of drinks and their main divisions . The literature review is based on the experimental part of analyzing selected beverages by high performance liquid chromatography with refractometric detection coupled to columns or alkyl ion-exchange phases. In conclusion, the results were compared to determine and comment . Nowadays the emphasis is on the correct functioning of the digestive tract. An important factor that supports the intestinal microflora is a prebiotic carbohydrate - tagatosa This could become tagatosa whose properties , production, metabolism in the body and any use is also included in the search . In the experimental part is listed possible optimization analysis of samples containing tagatosy on both types of columns in the HPLC system. The result is again commented in conclusion.
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Industrial production of ethanol
Flajs, Roman ; Zichová, Miroslava (referee) ; Omelková, Jiřina (advisor)
This bachelor thesis deals with ethanol production for food and car industry. The aim of this work is to give a summary of different kinds of raw material especially lignocelluloses and microorganisms used for its processing and fermentation. The thesis focuses especially on technological process of ethanol production and the utilization of different materials for fuel production.
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Sledování změn sacharosy v nápojích
Polesová, Denisa
The Master thesis was made at Department of Post-Harvest Technology of Horticulture Faculty of Mendel University in Brno in 2012/2014.The thesis is devided into the two parts, theoretical and experimental part. First of all I classified and described beverages and carbohydrates which is the theoretical part of the thesis. Next chapters describe individual form of carbohydrates, natural and artificial as well which occur in beverages. Apart of this, I also introduced its properties, occurrence, importance and possible methods of analysis.A great deal of attention of this thesis is given to the experimental part which is concentrated on speed of decomposition of sucrose in different pH, thus influence of action of citric acid and oxalic acid, which were mixed up in concentrations 1 and 5 %. The decomposition was also observed in fruit juices.The methods used for subsequent determination of carbohydrates were method of Luffa-Schoorla and enzymatic determination of carbohydrates with using of set K-SUFRG Megazyme.Efficiently operated inversion acids, mainly oxalic acid.
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Sweeteners (natural and artificial) used in the food industry
PIHLÍK, Pavel
The aim of this work is to introduce the sweeteners which are used in the food industry in the Czech Republic but also in the world. The basic sweetener which is a measure of the other sweeteners is regarded as sugar (sucrose). In this bachelor´s work, I described the history of the production of beet sugar in the Czech Republic, the products which are made of it and also its usage in food industry. Furthermore, I introduce the basic types of sweeteners by which we try to replace the beet sugar. I describe the history, production, characteristics and their usage. These are mainly the natural sweeteners which are divided into the carbohydrate (sucrose, fructose, glucose, honey, lactose and sugar alcohols), non-carbohydrate (stevioside, thaumatin) and artificial align (aspartame, saccharin, cyclamates, acesulfame-K, sucralose).
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