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Determination of sweeteners and preservatives in energy drinks by HPLC
Zídková, Anežka ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This master´s thesis is focused on simultaneous determination of sweeteners and preservatives in energy drinks by liquid chromatography coupled with DAD and ELSD detection. The method was optimized for determination of aspartame, acesulfame K, saccharin, sucralose, steviol glycosides, benzoic acid and sorbic acid. Analyses were carried out on the Poroshell 120 EC-C18 column (4.6 x 150 mm, 2.7 m, Agilent) using mixture of methanol, acetone and water with formic acid and trimethylamine as a gradient mobile phase at a flow rate 0,5 mL•min-1. Validation parameters were determined (limit of detection, limit of quantification, repeatability and recovery). The validated method was applied on real samples.
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Removal of selected organic pollutants from water using advanced oxidation processes
Dalajková, Nikola ; Vávrová, Milada (referee) ; Repková, Martina (advisor)
The aim of this diploma thesis is the determination of selected organic pollutants with a focus on artificial sweeteners in waste water from wastewater treatment plant (WWTP) Modřice and the subsequent degradation of the thus obtained concentrations in model water using advanced oxidation processes (AOP). Two sweeteners were determined, namely sucralose and saccharin found in waste water. Synthetic sweeteners are not sufficiently cleaned in the WWTP and penetrate the environment. Effective processes for removing organic substances, including alternative sweeteners, are AOP processes. These processes are based on reactions of highly reactive hydroxyl radical (OH·), which is produced by many chemical reactions. Generally, they use ozone (O3) and hydrogen peroxide (H2O2). On sampling, wastewater samples were treated with Solid Phase Extraction (SPE) and then evaluated by HPLC/MS (High Performance Liquid Chromatography). In observing the degradation of selected sweeteners, three AOP methods were used: O3/UV, H2O2/UV and O3/H2O2. For each of these methods, the efficiency of degradation of sucralose and saccharin was investigated. From the evaluated data it was found that the most efficient AOP process for removing artificial sweeteners from water is the O3/H2O2 method.
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SStudy of crystalline structure of polyhydroxybutyrate and nucleating activity of selected additives
Sedláček, Zbyněk ; Tocháček, Jiří (referee) ; Bálková, Radka (advisor)
This diploma thesis deals with study of crystalline structure of polyhydroxybutyrate (PHB), which contains different types of additives for studying of their nucleation activity and which were prepared by mixing. It is about boronitrid (BN), sacharin, hydroxapatit, plasticizer Tegmer a tree types of talc. Crystal structure was analysed by differential scanning calorimetry and x-ray diffraction, supramolecular structure was observed by optical microscopy (polarized and confocal laser scanning). Nucleating activity was evaluated by isothermal and non-isothermal crystallization made on calorimeter and heated table of optical microscope. There is not influence of additives on crystallographic structure, but additives affects number and size of spherulites including crystal domains defects, which can have impact on final mechanical properties. BN and talcs react as nucleating agents, other additives during low and high cooling speeds (vc) inhibit nucleation and in middle cooling speeds are without effect. Nucleating activity is not evaluated by numerically, because decrease of crystallization temperature together with vc is not linear. Results of direct methods are based on picture analysis, which is great benefit for understanding of crystal behaviour of PHB.
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Determination of sweeteners and preservatives in energy drinks by HPLC
Zídková, Anežka ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This master´s thesis is focused on simultaneous determination of sweeteners and preservatives in energy drinks by liquid chromatography coupled with DAD and ELSD detection. The method was optimized for determination of aspartame, acesulfame K, saccharin, sucralose, steviol glycosides, benzoic acid and sorbic acid. Analyses were carried out on the Poroshell 120 EC-C18 column (4.6 x 150 mm, 2.7 m, Agilent) using mixture of methanol, acetone and water with formic acid and trimethylamine as a gradient mobile phase at a flow rate 0,5 mL•min-1. Validation parameters were determined (limit of detection, limit of quantification, repeatability and recovery). The validated method was applied on real samples.
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Removal of selected organic pollutants from water using advanced oxidation processes
Dalajková, Nikola ; Vávrová, Milada (referee) ; Repková, Martina (advisor)
The aim of this diploma thesis is the determination of selected organic pollutants with a focus on artificial sweeteners in waste water from wastewater treatment plant (WWTP) Modřice and the subsequent degradation of the thus obtained concentrations in model water using advanced oxidation processes (AOP). Two sweeteners were determined, namely sucralose and saccharin found in waste water. Synthetic sweeteners are not sufficiently cleaned in the WWTP and penetrate the environment. Effective processes for removing organic substances, including alternative sweeteners, are AOP processes. These processes are based on reactions of highly reactive hydroxyl radical (OH·), which is produced by many chemical reactions. Generally, they use ozone (O3) and hydrogen peroxide (H2O2). On sampling, wastewater samples were treated with Solid Phase Extraction (SPE) and then evaluated by HPLC/MS (High Performance Liquid Chromatography). In observing the degradation of selected sweeteners, three AOP methods were used: O3/UV, H2O2/UV and O3/H2O2. For each of these methods, the efficiency of degradation of sucralose and saccharin was investigated. From the evaluated data it was found that the most efficient AOP process for removing artificial sweeteners from water is the O3/H2O2 method.
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Phytoextraction of Artificial Sweeteners from Aqueous Solutions
Luptáková, Dominika ; Smrček, Stanislav (advisor) ; Břichnáčová Habartová, Věra (referee)
The artificial sweeteners are currently worldwide used as food additives. In human organism they are only partially metabolized and then renally excreted. The big amounts of these abiogenic compounds contaminate municipal wastewaters. The efficiency of cleaning process in the sewage treatment plants (STP) is usually for cyclamate about 99 % and saccharine cca. 90 %. Acesulfame K is in STP practically not eliminated. Although most of artificial sweeteners are considered as good degradable, the residues were found in both surface waters and groundwaters. At long-term treatment can these compounds exhibited biological effect such as cancer genesis, gastrointestinal effects and/or surprisingly body mass increasing. The phytoextraction of saccharine and acesulfame K was experimentally studied by using of "in vitro" cultivated plants Helianthus annuus, Zea mays, and Brassica napus. The phytoextraction was monitored as decrease in medium concentration of tested substance in Murashige-Skoog cultivation medium. It was shown, that used species are able to extract tested substances and during 5 to 7 days 30 - 60 % of acesulfam K and 50 - 60 % of saccharine amounts disappear from cultivation medium depending of used plant species. The best extraction ability was observed at Helianthus annuus cultivars - 0.1...
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Low- and nonenergy sweeteners
Trnková, Lenka ; Orsák, Matyáš (advisor) ; Hniličková, Helena (referee)
Low- and no-calorie sugar subtistutes are compounds that provide food with its sweet taste. As the term suggests, they have lower or no food energy and usually are characterized by higher sweetness than sucrose. For that reason, these substances are especially used during the treatment of diabetes mellitus, to reduce the energy content of food or in prevention of dental caries.
Natural sweeteners were discovered a long time ago, during the search for sustenance. For example Stevia was used by South American Natives even before the European conquest of the territory. However, the history of artificial sweeteners is not too significant, because it relates to breaking the laboratory rules. That is how saccharin was invented in 1878.
Sugar substitutes are added to food on purpose, adjusting the taste or extending the shelf life of foods. In the EU, every approved sweetener has got an E-code, which is displayed on the label.
Sugar substitutes can be grouped according to their origin, their nutrition value or their chemical structure. This thesis discusses low- and no-calorie sugar substitutes that can be synthetic or natural. Mentioned synthetic sweeteners typically contain less then 21 kJ per portion. These intensive food additives possess many times the sweetness of sucrose. The main representatives of this group are saccharin, cyclamate, acesulfame K, sucralose and aspartame with its derivatives. The group of natural sugar substitutes constits of substances like erythritol, D-tagatose, trehalose, neohesperidin dihydrochalcone, stevioside and thaumatin.
There are some limitations confirmed by expert studies. For example, patients suffering from diabetes mellitus should mainly use synthetic sweeteners, because of their low nutritional value.
Even though in some states certain sweeteners are forbidden, safety studies say that there are no adverse effects, if the recommended daily intake is respected. Sugar substitutes, therefore, can be considered safe.
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SStudy of crystalline structure of polyhydroxybutyrate and nucleating activity of selected additives
Sedláček, Zbyněk ; Tocháček, Jiří (referee) ; Bálková, Radka (advisor)
This diploma thesis deals with study of crystalline structure of polyhydroxybutyrate (PHB), which contains different types of additives for studying of their nucleation activity and which were prepared by mixing. It is about boronitrid (BN), sacharin, hydroxapatit, plasticizer Tegmer a tree types of talc. Crystal structure was analysed by differential scanning calorimetry and x-ray diffraction, supramolecular structure was observed by optical microscopy (polarized and confocal laser scanning). Nucleating activity was evaluated by isothermal and non-isothermal crystallization made on calorimeter and heated table of optical microscope. There is not influence of additives on crystallographic structure, but additives affects number and size of spherulites including crystal domains defects, which can have impact on final mechanical properties. BN and talcs react as nucleating agents, other additives during low and high cooling speeds (vc) inhibit nucleation and in middle cooling speeds are without effect. Nucleating activity is not evaluated by numerically, because decrease of crystallization temperature together with vc is not linear. Results of direct methods are based on picture analysis, which is great benefit for understanding of crystal behaviour of PHB.
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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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