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Active substances in cereal products for baby food
Hurtová, Jana ; Pařilová, Kateřina (referee) ; Márová, Ivana (advisor)
Present bachelor thesis is focused on the study of antioxidant substances in cereal products for baby food. The theoretical part is aimed at describing the anatomical structure and chemical composition of cereal grain, characterization of antioxidants with the focus on natural antioxidants, the technology and nutritional parameters of cereal products. The experimental part deals with the content of phenolic compounds, flavonoids, and the total and reducing sugars in the total of 12 kinds of cereal products with different flavour – 5 types of oak pap, 3 types of fiber pap and 4 corn paps. The work includes the analysis of ascorbic acid by titration method and the analysis of tocopherol, carotenoids and catechins by high performance liquid chromatography as well. The highest content of total phenolics and flavonoids was found in corn pap with raspberries and also in cereal pap with chocolate. High levels of vitamins E and C were found predominantly in flavoured fiber pap.
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Preparation and characterization of foods and food supplements containing selected vitamins
Krupičková, Lucie ; Hoová, Julie (referee) ; Skoumalová, Petra (advisor)
The thesis is focused on preparation of protected form of vitamins for aplication to food and diatery supplemets. The theoretical part characterizes vitamins and describes their role in human organism. Furthermore, this chapter summarizes different methods of determination vitamins soluble in water and encapsulation of substances into liposomes. The last sections are focused on functional foods and dietary supplements. In experimental part, an optimalization of determination method was made. Selected vitamins were encapsulated into liposomes. Size, stability, encapsulation efficiency, long-term stability and long-term encapsulation efficiency after two weeks was determined there. All prepared liposomes were found to be stable enough. Furthermore, the vitamin solutions, liposomes and lyophilized particles were analyzed during the process of model digestion. The active forms of vitamins were degraded during the model digestion of vitamin solutions. Vitamins were gradually released from the liposomes and lyophilized particles into the digestive juice. The analysis of content declared by producer was executed for functional foods and dietary supplements. Finally, applications of protected form of vitamins into the food and dietary supplemets were created.
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Introducing of method of pyridoxine determination by liquid chromatography in food products and resources
Nechyba, Ondřej ; Benešová, Karolína (referee) ; Vespalcová, Milena (advisor)
This master‘s thesis deals with quantification of vitamin B6 in beverages, food supplements and raw materials in food industry. The literature retrieval part summarizes general information about vitamines, vitamine B6, nicotine acid and vitamine B1. Further on in this part there is described principle of high pressure liquid chromatography and quantification of individual vitamines. In the experimental there are listed used tools, apparatus and chemicals. There is described preparation of idividual samples of food supplements, energy drinks, multivitamine drinks, beers and brewer’s malts. This chapter also contains information about chromatographic separatory systems Shimadzu and SpectraSystem. The quantification was performed by high pressure liquid chromatography on a reverse phase with gradient elution and two ways of detection, fluorescent and spectrofotmetric. The result of experimental activities and vitamine content in analysed samples are presented in the next chapter. In the final contains summarization of results obtained in experimental part. The maser’s thesis was measured in the laboratory of Institute of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology.
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Encapsulation of vitamins and provitamins into nanoparticles
Martinusíková, Katarína ; Wikarská, Monika (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis is focused on the encapsulation of vitamins in liposomes and the subsequent observation of the properties of this form. The theoretical part is focused on the history of vitamins, their classification into groups, but mainly the general characterization of all vitamins. It describes their function in the human body, the consequences of their deficiencies and also the sources of their income. It also describes the technique of encapsulation in liposomes and their characterization and use in the food industry. The experimental part is focused on the preparation of specific liposomes of vitamins and their mixtures. These prepared liposomes are subsequently characterized by properties such as size, stability and encapsulation efficiency. Long-term stability of prepared liposome particles over 2 and 5 weeks were also investigated. In the conclusion of this thesis are summarized all the results of observations and the subsequent suggestion of the possible use of this technique in food products.
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Characterization of cereal products with fruit component for baby nutrition
Pražáková, Jana ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
Present bachelor thesis deals with the characterization of milk cereal products intended for baby food. The theoretical part focuses on the morphology of cereal grains, fortification, an overwiev of supplementary components used to fortification and their properties. For the practical part eight kinds of cereal dairy products of three different producers were chosen. In these products total polyphenols, total flavonoids, reducing and total saccharides and proteins were analyzed. The highest level of polyphenols was measured in product Sunar multicereal. The highest amount of flavonoids (more than 50 % of total phenolics) was found in Nestle fruit product. The highest level of total and reducing saccharides contained Nestlé honey flavour. High amount of proteins was found in products Sunar with multicereal flavour and pears with biscuits. Using HPLC/UV-VIS analysis vitamins C and E were determined. The highest content of vitamin C contained Nestlé with cookie lavor, while high vitamin E level was found in Sunar pear flavor and biscuits. Using HPLC/RI individual saccharides were examined. In all products high amount of lactose was found, mainly in the products of Sunar. Nestlé products contained mostly glukose, while in products Hami sucrose was detected as the most abundant saccharide.
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Monitoring of lipophilic vitamins and provitamins in children 's products and possibilities of their fortification
Maráčková, Adéla ; Hoová, Julie (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis deals with the study of lipophilic vitamins with a focus on children's food supplements. It designs own food supplement in the form of gum confectionery with a vitamin mixture encapsulated in liposomes. The theoretical part focuses mainly on the characterization of lipophilic vitamins and their monitoring in the market. The experimental part is focused on their determination in real food supplements (Marťánci, Vibovit Dino and Vitamin Code Kids). Extraction in chloroform and enzymatic methods were chosen as suitable methods of determination, both methods being evaluated chromatographically (HPLC). Finally, liposomes were prepared and characterized. Liposomes prepared in the same way were later added to the preparation of gum confectionery. Finally, several types of dietary supplements with liposomes were proposed, into which lipophilic vitamins were encapsulated. Design of the food supplement itself was in the form of a gum confectionery (in the shape of a gummy bear and a coffee bean) made of gelatin or a mixture of agar and alginate. The proposed dietary supplement was subjected to sensory analysis and its organoleptic properties were evaluated.
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Preparation and characterization of food and cosmetic products containing selected vitamins
Kubošová, Jana ; Pavelková, Renata (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis deals with the preparation and characterization of encapsulated forms of lipophilic vitamins in model conditions, focusing on cosmetic and food applications. The theoretical part describes the individual vitamins, their physiological effects, physical and chemical properties, sources and sequels of hypo/hypervitaminoses. Furthermore, their contribution in medicine, food industry and cosmetics, methods of determination and in the last part of the encapsulation method are discussed. Special attention is dedicated to the technique of particles encapsulation using liposomes, which was used in the practical part. The experimental part is focused on the study of liposomes of selected substances of vitamin nature. Namely, the issue of cholecalciferol, tocopherol and -carotene was addressed, for which a suitable method of determination was introduced. Subsequently, encapsulation of these substances and characterization of the prepared liposomes took place. Their size, stability and encapsulation efficiency, which reached high percentages, were determined. Liposomes were further put to the stability tests in digestive juices and model medium simulating cosmetic products. During the measured time, the release of encapsulated substances into the surroundings and their gradual degradation was monitored. At the end of the work, analytes were extracted from real foods and cosmetic products and the measured concentrations were compared with the declared values.
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Encapsulation of active substances and possibilities of their application in anti-aging products
Horváthová, Iveta ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The aims of this thesis were encapsulation of selected active substances and their possible application in cosmetic products with anti-aging effects. 6 kinds of active substances were studied – lipophilic vitamin E and vitamin A, hydrophilic vitamin B1 and vitamin B2, and phenolic compounds ferulic acid and chlorogenic acid. In theoretocal part, the general characteristics of active compounds and their use are described. It also includes the description of used methods. Practical part was focused on characterisation of active compounds from the perspective of antioxidant activity and encapsulation into liposomes from soy and sunflower lecithin. Encapsulation effectivity, size, stability and long-term stability of liposomes after four weeks were determined. The most suitable liposomes with active compounds were also tested for safety on human skin cells using the MTT test of cytotoxicity on keratinocytes HaCaT. Furthernore, 3 types of cosmetic products were prepared – day cream, night cream and skin serum. Each kind of cosmetic product was devided into 4 types – the product without any active compounds, the product containing free active compounds, the product with liposomes with active compouds and the product containing empty liposomes. As active compounds all our tested substances were used. Final products were tested 14 days on 15 female volunteers. Before and after products usage parametres of their skin were measured to analyze effect of products on skin rejuvenation. Volunteers were also rating sensory analysis of cosmetic products. The part of this thesis was also creating an online questionnaire about anti-aging cosmetics for publicity to find out the popularity of this kind of cosmetics.
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Analysis of active substances in honey
Jelénková, Zuzana ; Kubešová,, Jitka (referee) ; Márová, Ivana (advisor)
This diploma thesis was focused on biologically active compounds determination. 26 samples of honey, one sample of propolis and one sample of royal jelly were analyzed. Honey were harvested in year 2006 and 2007 and bought in retail chain, special shops and directly from bee-keeper. Samples were analyzed by titration, spectrofotometry, LC/MS and RP-HPLC methods. The study was focused on analysis of antioxidants. Followed groups of antioxidants were determined: flavonoids, catechins, carotenoids, vitamins E, C, A. Authenticity of quality was determined by hydroxymethylfurfural analysis. Average values of total antioxidant capacity ranged (12.75-137.49) mmol .100 g-1. Average values of total phenolic ranged (8.51-61.34) mg .100 g-1 and average values of total flavonoids ranged (0.75-6.04) mg .100 g-1. Honey samples contained (41.83-585.10) g .100 g-1 of rutin, (9.30-313.40) g .100 g-1 of myricetin, (6.5-171.90) g .100 g-1 of luteolin, (3.19-436.37) g .100 g-1 of quercetin, (2.10-242.66) g .100 g-1 of apigenin, (0.15-105.12) g .100 g-1 of caempferol and (0.07-17.52) mg .100 g-1 of naringenin. From group of catechins there were measured (5.98-310) g .100 g-1 of catechin, (17.77-486.29) g .100 g-1 of epicatechin, (0.18-64.90) g .100 g-1 of catechin gallate and (0.59-140.56) g .100 g-1 of epicatechin gallate. From lipophilic compounds the most abundant in honey samples was tocopherol, its value ranged (29.20-8531.17) g .100 g-1. Content of ascorbic acid ranged (0.65-4.65) mg .100 g-1. Content of hydroxymethyl.furfural. ranged (0.26-4.06) mg .100 g-1. By LC/MS method luteolin, naringenin, protocatechin acid, coffee acid and p-cumaric acid in honeydew were detected and, furthermore, kyanidin and pinocembrin in floral honey were found. Mono-floral honey contained biologically active compounds the most, imperceptibly less contained multi-floral honey and honeydew honey. Acacia honey contained the lowest amount of biologically active compounds.
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Možnosti stanovení vybraných parametrů u energetických nápojů
Ošťádalová, Aneta
The bachelor thesis is a literary research devoted to energy drinks. The introductory part of the thesis describes the general characteristics of energy drinks, their history and legislation. Next part of the work is focused on the availability of energy drinks on the Czech market, their production and individual raw materials used for production. The thesis further describes natural alternatives that are used for the production of energy drinks, which include Panax ginseng, Guarana, Ilex paraguariensis, Ginkgo biloba and Cola nitida. The last part is devoted to the physical and chemical methods used for the analysis of individual components of energy drinks, such as the determination of carbohydrates, organic acids, vitamins, alkaloids, antioxidants, amino acids, inositol and glucuronolactone.
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