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Stability and properties of combined beverages and fruit concentrates
Klatová, Kamila ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This diploma thesis deals with the stability and basic properties of combined beverages and fruit concentrates. The theoretical part describes the production and use of fruit concentrates. Furthermore, the work deals with anthocyanic pigments and phenolic substances. The principle and instrumentation of liquid chromatography and electron paramagnetic resonance were described. In the next subchapter, the methods of determination of total anthocyanins and phenolic substances were described. The experimental part of the thesis described the determination of soluble solids, viscosity and antioxidant activity. The total content of phenolic compounds were determined by the Folin-Ciocalteua method and the total anthocyanins were determined by the pH-differential method. In the samples were determined cyanidine-3-glucoside and cyanidin-3-galactoside by liquid chromatography.
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Aronia as a raw material for cosmetic production
Palkovská, Kateřina ; Sýkora, Michal (referee) ; Zemanová, Jana (advisor)
This bachelor thesis deals with extraction of polyphenols from fruits and leaves of aronia and consequent use of obtained extract in cosmetic production. In the theoretical part are information about the origin of the aronia, the botanical characteristics of Aronia Melanocarpa and about its utilization. Furthermore, the chemical composition of the plant material of the aronia is described, which is also common for fruits. At the end of the theoretical part are described extraction and separation techniques, methods of determination of total polyphenolic compounds and brief characteristics of the material safety data sheet. The experimental part describes the optimization of the prepared extract so that the extract contains as many polyphenolic compounds as possible. 50% ethanol at room temperature was shown to be optimal for leaf and fruit extraction, and the maceration time was found to have a significant effect on the polyphenolic compounds obtained. For the obtained optimized macerate, some chemical and physical properties such as pH, density, refractive index were determined for the purpose of producing a material safety data sheet and product specification. At the end of the experimental part were prepared cosmetic products with the addition of macerate from crushed aronia fruits.
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Obtaining and complex charaterization of Aronia spp. extracts
Seidlová, Kateřina ; Zemanová, Jana (referee) ; Veselá, Mária (advisor)
Aronia (Aronia melanocarpa) is a berry fruit with distinctive sensory characteristics and health-promoting properties. Polyphenols are the main bioactive compounds found in aronia including natural pigments – anthocyanins. Bioactive compounds are usually obtained from natural materials by extraction, in this work, two methods of extraction were compared – maceration and PHWE. Based on the total phenolic content, maceration was chosen as a more suitable method and then was optimized with statistical model – Design of Experiment. Optimal conditions were set to temperature of 30 °C, extraction agent 50 % ethanol, solid-solvent ratio 10 g per 50 ml and time of extraction for 30 minutes. Extract obtained under these conditions was characterised by total phenolic content – 1441 ± 90 mg/100 g DW, total anthocyanin content 943 ± 8 mg/100 g DW and antioxidation activity by ABTS 24,78 ± 0,09 molTE/g. In total of 25 volatile compounds were indentified in the optimal extract with content > 0,5 %. Major part created aldehydes and esters, with the main compounds being benzaldehyde (32,25 %) and methyl hexanoate (21,37 %).
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Aronia – the source of bioactive compounds
Štumarová, Klára ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The aim of this bachelor thesis is to research the possible antimicrobial activity of aqueous and ethanolic extracts of aronia berries and tea mixture containing aronia. Also, the antioxidant activity and the concentration of the biologically active substances - polyphenols, flavonoids and anthocyanins was determined. Theoretical part contains a summary of basic information about Aronia melanocarpa, chemical composition, use and health effects of substances contained in its fruits. The experimental part focuses on the antimicrobial activity of the extracts on microorganisms Bacillus subtilis, Serratia marcescens and Micrococcus luteus. Farther there is spectrophotometrical determination of antioxidant activity, polyphenolic compounds, flavonoids and anthocyanins. From the experiment results flow that the extracts have almost none antimicrobial ability except tea mixture extracted with hot water. This extract has inhibitory effect on M. luteus and growth supportive effect on B. subtilis. It has been found that aronia fruits and tea mixture are rich in polyphenols and flavonoids.
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Lyophilized fruits - chemical properties and processing possibilities
Horáková, Klára ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This diploma thesis deals with chemical analysis of selected frozen, dried and lyophilized fruit, specifically Mirabelle de Nancy, Aronia Nero and blackcurrant varieties Gairn Ben and Ben Lomond. In the theoretical part taxonomy and botanical characteristics of selected fruit are given. Subsequently the utilization of fruit in food industry is described. In common the theoretical part focuses on lyophilisation and drying of fruit and raw food. Further in this part the methods of phenolic substances, anthocyanins, antioxidant capacity and finally ascorbic acid and carbohydrates value measurements are specified. In the experimental part the value were determined measurements of biologically active substances: total phenols, total anthocyanins, antioxidant capacity, ascorbic acid and carbohydrates. For all value measurements were compared the frozen, dried and lyophilised samples of every single fruit. Further, the every sort of fruit were compared to each other. Following the raw food preparaon a product of lyophilised fruit was made.
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Possibilities of preparation combined drinks from selected fruits
Zábranská, Miroslava ; Vránová, Dana (referee) ; Vespalcová, Milena (advisor)
This thesis deals with the preparation of the combined alcoholic beverages based on wine and fruit juices. The fruit juices were obtained from the selected fruits as honeysuckle, mulberry, dogwood, rose hips, elderberry, buckthorn and aronia. Some chemical properties e. g. total fenolics, total anthocyanins, vitamin C and sacharides were determined for characterization of the mentioned juices. As well as chemical parameter of juices, the same chemical parameters were determined on wine. There were prepared three sets of combined beverages from wine and juices. The two best evaluated beverages were chosen on the basis of their sensory evaluation. In the end, the same chemical properties were determined in both particular juices and resulting beverages.
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Study of the antioxidative potential of selected fruit marcs
Havlíčková, Barbora ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
Subject of this bachelor thesis was antioxidant activity of selected kind of fruits. Among selected kinds were the marc of red and white grapes, moldings from red elderberry and aronia. Two species of made capsules from marcs of white grapes and aronia were also subjected to analysis. Results of this bachelor thesis are summarized to four chapters. The first chapter compares the water content of drying at 40 ° C and 105 ° C. In the second chapter, the results of extraction in different proportions of solvent mixture ethanol - water and results of extraction in prepared artificial gastric juice are discussed. As a result, the water – ethanol mixture was a more effective solvent than artificial gastric juice. The third chapter deals with the results and discussion of the determination of the total content of phenolic substances. For the solvent mixture, the largest amount of polyphenols in the red vine marc was determined to be 43,56 mg.g-1, while in gastric juice the largest content in the elderberry was determined to be 11,89 mg.g-1. Capsules were also extracted in gastric juice, and 2,53 mg.g-1 was found in aronia tablets, while 5,93 mg.g-1 in white grape tablets. The last chapter compares the results of TAA measurements using the TEAC and EPR methods. The EPR method was more suitable for much diluted solutions than the TEAC method. The results of this work show that there is a large number of polyphenols and other antioxidants in the moldings that affect the overall antioxidant activity. Marcs have great potential for use as natural dyes or can be used to make a food supplement.
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Use of capillary electrophoresis to determine a selected group of flavonoids
Tran Xuan, Tiep ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
In recent years, the use of natural medicinal properties of plants has again come to the forefront of interest of the public. Because of their therapeutic properties, these plants are commonly used in alternative treatments for minor ailments. This thesis deals with the determination of polyphenolic acids in extracts from aronia, echinacea, tetradenia and centella. One of the aims of the thesis was to compare the amount of polyphenolic acids in individual plants with their antioxidant properties. The theoretical part includes a general introduction to flavonoids, introduction to polyphenolic acids, introduction to the principles of capillary zone electrophoresis and a summary of selected foreign studies for the determination of flavonoids. An important chapter of the theoretical part is a description of individual plants with an explanation of their possible therapeutic use. The experimental part is devoted to the process of optimization of electrophoretic determination of selected polyphenolic acids and evaluation of their content. It was found that in the extracts six representatives of polyphenolic acids occur in minimal amounts, often below the limit of quantification or detection of the method.
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Use of capillary electrophoresis to determine a selected group of flavonoids
Tran Xuan, Tiep ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
In recent years, the use of natural medicinal properties of plants has again come to the forefront of interest of the public. Because of their therapeutic properties, these plants are commonly used in alternative treatments for minor ailments. This thesis deals with the determination of polyphenolic acids in extracts from aronia, echinacea, tetradenia and centella. One of the aims of the thesis was to compare the amount of polyphenolic acids in individual plants with their antioxidant properties. The theoretical part includes a general introduction to flavonoids, introduction to polyphenolic acids, introduction to the principles of capillary zone electrophoresis and a summary of selected foreign studies for the determination of flavonoids. An important chapter of the theoretical part is a description of individual plants with an explanation of their possible therapeutic use. The experimental part is devoted to the process of optimization of electrophoretic determination of selected polyphenolic acids and evaluation of their content. It was found that in the extracts six representatives of polyphenolic acids occur in minimal amounts, often below the limit of quantification or detection of the method.
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Obtaining and complex charaterization of Aronia spp. extracts
Seidlová, Kateřina ; Zemanová, Jana (referee) ; Veselá, Mária (advisor)
Aronia (Aronia melanocarpa) is a berry fruit with distinctive sensory characteristics and health-promoting properties. Polyphenols are the main bioactive compounds found in aronia including natural pigments – anthocyanins. Bioactive compounds are usually obtained from natural materials by extraction, in this work, two methods of extraction were compared – maceration and PHWE. Based on the total phenolic content, maceration was chosen as a more suitable method and then was optimized with statistical model – Design of Experiment. Optimal conditions were set to temperature of 30 °C, extraction agent 50 % ethanol, solid-solvent ratio 10 g per 50 ml and time of extraction for 30 minutes. Extract obtained under these conditions was characterised by total phenolic content – 1441 ± 90 mg/100 g DW, total anthocyanin content 943 ± 8 mg/100 g DW and antioxidation activity by ABTS 24,78 ± 0,09 molTE/g. In total of 25 volatile compounds were indentified in the optimal extract with content > 0,5 %. Major part created aldehydes and esters, with the main compounds being benzaldehyde (32,25 %) and methyl hexanoate (21,37 %).
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