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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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Characterization of pectin by ultrasonic spectroscopy
Trtek, Jan ; Kalina, Michal (referee) ; Hurčíková, Andrea (advisor)
Pectin solutions of various concentration in water has been investigated using high resolution ultrasonic spectroscopy. Furhermore, the influence of solvent on the properties of solutions by dissolving pectin in 0.15 M aqueous solution of sodium chloride and buffer PBS at pH 7.4. For comparison the properties of the pectin solutions were compared with solutions of pectate. It was found that pectine changes characteristics in differenet solutions. These changes have been observed due to changes in the parameters of ultrasonic waves.
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Influencing of caffein absorption from cola-type beverages
Osecká, Karolína ; Márová, Ivana (referee) ; Pekař, Miloslav (advisor)
This diploma thesis was focused on basic physicochemical properties of caffeine and investigation of the interaction between the polysaccharide sodium hyaluronan (HA), pectin (PEC) or lignohumate (HUM) and the alkaloid caffeine (CAF). The reason why this thesis was focused on study of aqueous solutions of hyaluronan or pectin with caffeine is that the presence of polysaccharide- caffeine complex could be beneficial for slowing the absorption of caffeine. In the theoretical part of the diploma thesis there is described a group of alkaloids, which caffeine belongs to and also polysaccharides hyaluronic acid and pectin. The most attention has been paid to caffeine, its properties and effects on the human organism. This diploma thesis also deals with non-alcoholic beverages with caffeine, 4-methylimidazole, and phosphoric acid. The last chapter of the theoretical part is dedicated to fluorescence spectroscopy. In the experimental part of this work I deal with the basic properties of caffeine and interaction between the caffeine and selected polysaccharides or lignohumate. At first, the chemical and physical properties of caffeine were determined. Based on these results the interaction of caffeine and hyaluronan or pectin was studied by using the fluorescence and absorbance. The HA of molecular weight of 1,7 MDa and pectin from citrus fruits were chosen for the study of the interaction with the caffeine. These two substances were mixed with the caffeine of concentration contained in Coca-Cola. The results of interaction that would lead to the influence of the emission or absorption properties of caffeine, were not proved. As a part of the work there was determined how pectin behaves in strongly acidic solution and then there was monitored the pH, conductivity and solubility of caffeine in water by using thermogravimetry and visual experiments. The obtained results of the interaction of hyaluronan-caffeine, pectin caffeine or caffeine-lignohumate can be used for description of the behavior of caffeine in the presence of selected polysaccharides and natural organic substance.
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Pectin - its properties and industrial applications
Odstrčilová, Eva ; Vránová, Dana (referee) ; Omelková, Jiřina (advisor)
This thesis deals with pectins substances in food processing and pharmaceutical industry. Pectin is very using component in food processing products, mainly due to jelly and thickening ability. The thesis is dedicated plant cell wall, where is located pectin including other material component of plant cell wall. Further it is described structure of pectin, including his production and use in industry. The last part of the thesis is dedicated enzymatic degradation of plants origin materials. Pectin is very using, but its structure and biosynthesis is still not fully explored.
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Immobilization of pectinase on selected carriers
Reichstädter, Marek ; Zichová, Miroslava (referee) ; Omelková, Jiřina (advisor)
The theoretical part of this bachelor thesis deals with the definition of pectin substances as substrates for pectolytic enzymes. It also describes the changes in properties of enzymes due to enzyme immobilization, various methods of immobilization and application of immobilized enzymes. The experimental part examines the preparation by immobilization of commercially used pectolytic complex Rohament P by sorption on the polymeric carrier made of polyethylene tereftalate (PETE) bottles, what is a new patent of BUT. The main observed property was the enzyme activity of all preparations, it was determinated by Somogyi method and spectrometry – for both free and immobilized enzymes in dependence on the quantity of immobilized enzyme adsorbed onto specific weight of carries. The difference in effects change between the free and immobilized enzyme by measuring the viscosity decrease of the substrate depending on the degradation of glycosidic bonds was also studied.
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Representative of small fruit - gooseberry and its nutritional characteristics
Mohelský, Tomáš ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with less known fruit - gooseberry (Ribes uva-crispa). The theoretical part describes the botanical characteristics of gooseberry: description of plant breeding and plant forms. Then selected varieties, pests and diseases of gooseberry are described. The following chapters include a list of active substances in the gooseberries and its treatment. In conclusion, the theoretical part describes the most common methods for the determination of pectin in fruit. The experimental part deals with the optimization of spectrophotometric methods for the determination of pectin and determination of pectin itself in gooseberry.
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Rowanberry - nutritional characteristic and utilization in grocery
Andrlová, Kateřina ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
Bachelor elaborate is focused on one the less used species of small fruits - rowanberries. It gives an overview of the particular biologically active substances in this fruit and the use of the fruits in the human diet. Introduction is focused on the botanical description of rowan - Sorbus. There are presented the best known species of genus rowan. The greatest attention is paid to the type of Sorbus aucuparia which provide sweet variety and nutritional value of the fresh fruits. The second part is devoted to the description of biologically active substances contained in food rowanberries. The most valuable of them are vitamin C, flavonoid compounds (quercetin, campferol), phenolic compounds (chlorogenic acid) and pectins. Possibility of processing rowanberries in a variety of products are presented in next part. They are made of these compotes, jams, candied fruits, jellies and juice. Can be used for production of wine, cider and liqueur. In conclusion, there are described methods for determination the content of selected substances rowanberries (vitamin C, pectins). There are mentioned here primarily manual methods.
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Utilisation of plant origin waste
Habáníková, Kamila ; Šťavíková, Lenka (referee) ; Omelková, Jiřina (advisor)
This thesis describes properties and utilization and specifies the composition of organic plant waste produced during industrial processing. By cultivation of specific micro-organisms from this waste material it is possible to produce enzymes that have further beneficial industrial utilization. The experimental part of this thesis deals with the production of enzymes from the applied waste material grape pomace with the help of chosen micro-organisms. Waste, its processing and utilization is and always will be a key issue in our society.
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