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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 the presence of phenolic substances and their antioxidant activity in food products containing rosehip (Rosa canina L.)
Hronová, Vendula ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor's thesis monitored the content of bioactive substances and antioxidant activity in the jams made of the fruit of rose hips (Rosa canina L.). The jams were sweetened with various sweeteners such as cane sugar, beet sugar, erythritol and stevia. Moreover, the rheological properties of jams were determined. The properties of home-made jams prepared from rosehip fruit were compared with the commercial jam. Another aim was to determine whether the by-products received after the production of jams could serve as beneficial sources of bioactive substances after the preparation of water extracts. The content of carbohydrates, polyphenols, flavonoids, and antioxidant activity were determined in jams and extracts spectrophotometrically. Next, the spectrophotometric detection of pectin, the chemical characterization of jams by infrared spectrometry, and the spectrophotometric determination of the jam colour were performed. The concentration of bioactive substances in jams was influenced by the geographical location and the time and weather conditions of harvest. The rheological properties and pectin content of the jams depended on the type of the used sweetener. The assessment of the water extracts prepared from the by-products after jam production and from the dried fruits of rosehip showed the high content of bioactive substances and high antioxidant activity in all tested extracts. The presented work points out that it is possible to prepare jams with superfood properties from the fruit of rose hips and extracts with high antioxidant activity.
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Prebiotic sweetener tagatose
Jurečková, Zuzana ; Vránová, Dana (referee) ; Vespalcová, Milena (advisor)
This sweetener, D-tagatose, has numerous advantages, which would eventually be able to use in the food industry. It summarizes the properties of Dtagatose, physical and also chemical, the possibility of production from lactose or bacterial action on Dtalitol. The basic information about the properties of Dtagatosy also discusses the actual metabolism of Dtagatose, prebiotic properties and their effect in the gastrointestinal tract. Dtagatose is a proposed new sweetener, because the possibility can not be missed in certain applications tagatose in a different types of foods for example confectionery. And positive qualities in comparison with sucrose. This comparison is made to examples of disease associated with excessive use of conventional sweeteners sucrose. This paper also discusses possibilities Dtagatose determination in foods by different methods.
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Artificial sweeteners and their potential impact on the ecosystem
Vavrčíková, Veronika ; Mravcová, Ludmila (referee) ; Zlámalová Gargošová, Helena (advisor)
This diploma thesis deals with the determination and ecotoxicological assessment of artificial sweeteners. The diploma was focused on monitoring the most commonly used sweeteners, which includes acesulfam-K, cyclamate, saccharin and sucralose. These sweeteners were analyzed by liquid chromatography with mass spectrometry, using solid phase extraction for their concentration. The samples for their determination were taken from wastewater treatment plant in Modrice. Artificial sweeteners are synthetically produced substances, which is the main reason for their occurrence in waste water. Some of them are not efficiently removed from the wastewater treatment plant and penetrate into the environment. Analysis of the samples was found, that sucralose penetrates into the environment. The ecotoxicological effect of the sweeteners was evaluated via aquatic organisms, namely on the freshwater crustaceans Thamnocephalus platyurus and Daphnia magna, on the water plant Lemna minor, and the battery of tests was supplemented by a representative of the destructors Vibrio fischeri. For all sweeteners, LC20, EC20 and IC20 values were determined. For some sweeteners, LC50, EC50 and IC50 values were also determined. During testing, saccharin represented the highest toxicity.
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Hodnocení kvality bylinných sirupů
Hrabiecová, Vendula
The thesis deals with a production of atypical formula of herbal syrups. The theoretical part describes ingredients for the syrups production, ingredients they contain, techno-logical procedure of the production and legislative requirements for the syrups produc-tion. In the practical part, two syrups were produced according to their own formula using three different sweeteners. The samples were sensory evaluated and using Statis-tica 14 and Microsoft Excel software. The samples were evaluated by two groups of students. The first group consist-ed of 47 students who were not experienced evaluators. A 5-point scale was prepared for them. The second group consisted of 10 students who were experienced evaluators. An unstructured 100 mm hedonic and intensity scale was prepared for them. The samples were evaluated based on preference of the sweeteners and herbal formula. The first group of evaluators (n = 47) preferred cane sugar as a sweetener in syrups. Based on the preference of the herbal formula, the results of both samples were equal. The second group (n = 10) preferred beet sugar in the first syrup and cane sugar in the second one. Based on the popularity of the composition of the samples, the first formula was chosen as having a higher potential for industrial production.
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Diabetic versus eating in public establishments (candy store) - production of ice cream for diabetics.
KRČMÁŘOVÁ, Lucie
In my bachelor thesis I deal with one of the most common diseases of civilization, diabetes mellitus. The theoretical part contains historical facts, information about anatomy of the pankreas, epidemiological characteristics and types of diabetes, as well as diagnosis, treatment and complications of this disease. In the part dealing with nutrition, I deal with macronutrients and micronutrients found in diabetic nutrition, glycemic index, recommendations for diabetics and the main topic of my bachelor thesis, sweeteners. In the practical part I deal with the production of two types of fruit sorbets (strawberry and raspberry) with the addition of artificial sweetener - sucralose. This ice cream is tested on five healthy volunteers and five volunteers with 1. and 2,. type of diabetes compared to strawberry and raspberry sorbet with sugar. The result of the research is to found out how individual types of the ice cream affect the glycemic curve of healthy volunteers and volunteers with diabetes.
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Consumption of energy drinks by pupils at a selected lower secondary school
Kunešová, Klára ; Thorovská, Alena (advisor) ; Zvírotský, Michal (referee)
Consumption of energy drinks by pupils at a selected lower secondary school ABSTRACT The presented bachelor's thesis deals with the issue of energy drinks consumption by pupils at a selected lower secondary school. The concept energy drink is described in the introduction to the theoretical part of the thesis. Furthemore, the theoretical part of the thesis is dedicated to the description of the most common components in energy drinks. Subsequently, the thesis focuses mainly on the amount of sweeteners in selected energy drinks on the Czech market. In the practical part of the thesis there is a questionnaire survey investigated among pupils at the lower secondary school in Český Brod, where their general awareness of energy drinks is ascertained. KEYWORDS Energy drinks, vitamins, taurine, caffeine, sweeteners, questionnaire survey, lower secondary school, consumer behaviour
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Study of the presence of phenolic substances and their antioxidant activity in food products containing rosehip (Rosa canina L.)
Hronová, Vendula ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor's thesis monitored the content of bioactive substances and antioxidant activity in the jams made of the fruit of rose hips (Rosa canina L.). The jams were sweetened with various sweeteners such as cane sugar, beet sugar, erythritol and stevia. Moreover, the rheological properties of jams were determined. The properties of home-made jams prepared from rosehip fruit were compared with the commercial jam. Another aim was to determine whether the by-products received after the production of jams could serve as beneficial sources of bioactive substances after the preparation of water extracts. The content of carbohydrates, polyphenols, flavonoids, and antioxidant activity were determined in jams and extracts spectrophotometrically. Next, the spectrophotometric detection of pectin, the chemical characterization of jams by infrared spectrometry, and the spectrophotometric determination of the jam colour were performed. The concentration of bioactive substances in jams was influenced by the geographical location and the time and weather conditions of harvest. The rheological properties and pectin content of the jams depended on the type of the used sweetener. The assessment of the water extracts prepared from the by-products after jam production and from the dried fruits of rosehip showed the high content of bioactive substances and high antioxidant activity in all tested extracts. The presented work points out that it is possible to prepare jams with superfood properties from the fruit of rose hips and extracts with high antioxidant activity.
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Sugar substitutes
Žuffová, Frederika ; Drastík, Martin (advisor) ; Kuchařová, Monika (referee)
The aim of diploma thesis "Sugar substitutes" was to create a list of sugar substitutes and review their impact on human health. It analyzes the realtionship of sugar substitutes to obesity, diabetes and caries. Diploma thesis discusses the possibilities of using sugar substitutes and their characteristics. Thesis includes information about acceptable daily intake of each sweetener and comparison its sweetness to sucrose. The brief description of every group of food additives and chapter about valid legislation are also parts of this thesis. Key words: sugar substitutes, artificial sweeteners, additives, acceptable daily intake, diabetes mellitus, obesity, caries
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Využití náhradních sladidel v nealkoholických nápojích a jejich vliv na senzorickou jakost
TOLKNEROVÁ, Denisa
The subject of this thesis was to evaluate the use of sweeteners in a selected group of soft drinks from the viewpoint of the sensory quality. Using selected methods of sensory analysis were evaluated four samples of soft drinks with lemon flavor. The first sample A - Sprite contained aspartame, acesulfame K and fructose - glucose syrup. The second sample B - Slice consisted of the aspartame and acesulfame Ksweeteners. Sample C - Lemon contained only sugar and last sample D - Santerre, was composed of aspartame, acesulfame K and sodium saccharin. The evaluators were divided into two groups according to age. The first group of respondents was composed of students from the University of South Bohemia in the age of 18-27 years. The second group was composed of randomly selected people aged 40+. The aim of the thesis was to determine whether there is a disparity between the groups. Top rated sample became the sample A - Sprite. Differences occurred in sample B and C. Sample B which contains aspartame and acesulfame K was preferably evaluated bythe first group, whereas the second group consisting of older respondents evaluated preferably sample C Lemon. Lemon sample contains only sugar and its taste is therefore less noticeable or even perceived as without flavour, based on the evaluated results.The lowest rated sample was unambiguously sample D, which contains sweetener aspartame, acesulfame K and sodium saccharin. Part of this work was a questionnaire for consumers.Its main aim was to find out what mostly influences respondents when buying soft drinks, what attitude artificial sweeteners they have and if they find the composition of soft drinks determinative.
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