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Development of a new type of energy drinks containing natural active components
Vysoká, Marie ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The aim of this thesis is the development and preparation of a new energy drink. The theoretical part of the thesis focuses on the comparison of the drinks available in market, the presentation of the main active ingredients and the proposal of enriching the new energy drink. It also describes the possibility of using an encapsulation and the method used to determine specific compound in energy drink or encapsulated particles. In the experimental part of the work, at the beginning, the main content of energy drinks were characterized, for instance caffeine, sugar, polyphenol and vitamin C. Subsequently the energy drink based on selected types of loose teas that were enriched with the encapsulated extract of acai, acerola, maca, goji and ginseng was designed. All extracts contained large amounts of polyphenols and antioxidants. In addition, acerola extracts contained very high amounts of vitamin C. Two types of particles, alginate particles and liposomes were prepared for encapsulation. For all particles, encapsulation efficiency, size, stability, and antioxidant activity were determined. Long-term stability was then monitored within three months. The particles were also exposed to artificial gastric, pancreatic and bile juice. All tested particles showed very good encapsulation efficiency. In terms of long-term storage stability in an aqueous environment. Particularly liposome particles, which also showed high stability by zeta potential measurement, were suitable. On the contrary, in case of alginate particles, when stored in an aqueous medium, the release of active substances occurred. Finally, an energy drink was created and subjected to sensory analysis. The best energy drink was based on black or green tea with alginate particles acai, goji and ginseng.
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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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Characterization of beverages and food supplements containig caffeine
Patočková, Klára ; Pekař, Miloslav (referee) ; Márová, Ivana (advisor)
This master thesis is focused on characterization of some energy drinks and formulation of their modified composition. The theoretical part was focused on summary of energy drinks and some of their natural components - guarana, goji as well as on techniques of encapsulation. In the experimental part concentrations of caffeine, vitamin C, polyphenols and carbohydrates in commercially purchased drinks was evaluated. Subsequently, three kinds of particles (particles with caffeine, particles with guarana and particles with guarana and goji) by 6 different techniques were prepared. The efficiency of encapsulation was determined by HPLC/UV-VIS (caffeine, vitamin C) and by spectrophotometry (phenolics). Stability of the particles was followed in real food and in a model physiological environment of artificial digestive juices. Size of prepared particles was determined by dynamic light scattering. In this work it was found that particles with best activity and stability were obtained by encapsulator. For manual particles the best results were found in the liposome particles. Liposomes exhibited the smallest particle size, the highest efficiency encapsulation, excellent stability in real food and juices and the best value of zeta potential.
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Development of new type of energy drinks based on coffee with active substances
Dudrová, Markéta ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
This bachelor thesis deals with development and preparation of new energy drinks with active plant component in free and encapsulated form. The theoretical part is focused on characterization of the energy drinks, their components and properties. The experimental part deals with the preparation of plant extracts, their characterization and subsequent encapsulation into liposome particles. All particles were determined for size, colloidal stability, long-term stability, antioxidant activity and encapsulation efficiency. Energy drinks based on various types of coffee were prepared and enriched with free or encapsulated guarana, goji, matcha or cocoa extract. In prepared energy drinks the content of caffeine, sugar, phenolics and antioxidant aktivity was monitored. Finally, selected energy drinks were subjected to sensory analysis, where appearance, color, smell and taste were evaluated.
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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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Development of new type of energy drinks based on coffee with active substances
Dudrová, Markéta ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
This bachelor thesis deals with development and preparation of new energy drinks with active plant component in free and encapsulated form. The theoretical part is focused on characterization of the energy drinks, their components and properties. The experimental part deals with the preparation of plant extracts, their characterization and subsequent encapsulation into liposome particles. All particles were determined for size, colloidal stability, long-term stability, antioxidant activity and encapsulation efficiency. Energy drinks based on various types of coffee were prepared and enriched with free or encapsulated guarana, goji, matcha or cocoa extract. In prepared energy drinks the content of caffeine, sugar, phenolics and antioxidant aktivity was monitored. Finally, selected energy drinks were subjected to sensory analysis, where appearance, color, smell and taste were evaluated.
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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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The effects of energy drinks on the human organism and the level of information on this issue among adolescents.
ANDRÝSKOVÁ, Zuzana
This diploma thesis deals with the effects of energy drinks on the human organism and the importance of energy drinks in the dietary regime for adolescents in the Czech Republic. The theoretical part of the diploma thesis describes energy drinks, presents the history of beverage production, current market and consumption of these beverages in the world. The theoretical part also desribes in more detail the individual components of energy drinks and their effects on the human organism. In the theoretical part, the period of adolescence is characterized, and appropriate nutrition, drinking regime and movement in adolescent life are presented as well. The practical part analyzes the level of consumption of energy drinks by adolescents, their awareness of the composition of drinks and possible adverse effects after consumption. The analysis is based on quantitative research, which was conducted using an anonymous questionnaire survey. The obtained data are processed in graphical and tabular form.
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Analysis of drinking mode of university students Czech republic
VESELKOVÁ, Barbora
The diploma thesis deals with analysis of the drinking regime of students of the Technical and Economic University (VŠTE) in České Budějovice. The theoretical part contains informations of the drinking regime in general, the suitability of widely discussed and used beverages. At the end of the theoretical part are the best recommendations, which todays literature, studies and other sources can offer. I have used questionnaire survey for the quantitative research. A total of 1515 students of the Technical and Economic University in České Budějovice have attented this questionnaire survey. Obtained answers are then evulated and compared with given hypotheses in the practical part.
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Development of massmedial communication of energy drinks between 2010 and 2015 with a focus on television advertising
Mošnová, Kamila ; Novák, Michal (advisor) ; Přibil, Jiří (referee)
The bachelor thesis defines mass media and the forms it can acquire. It shows their importance in marketing communication and lays more emphasis on advertising and television. This thesis is specialized on monitoring of marketing communication of energy drinks brands while the theoretical part describes its most frequently used forms. The practical part is focused on the television commercials in the time period between years 2010 and 2015. It evaluates the situation of television commercials promoting energy drinks on the Czech market in individual years of given period. It also monitors their development in time, and based on the discovered conclusions appraises the importance of television advertising nowadays.
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