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Analysis of active phenolics in some cereal products
Vondráčková, Hedvika ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
Presented diploma thesis was focused on study of phenolic substances in various cereal products. Flours, brans and germs from various cereals, flakes and extruded cereals were chosen as samples. Phenolic substances were analyzed by spectrophotometry, RP-HPLC/UV-VIS and RP-HPLC/PDA/ESI-MS. Studies of saccharide content which were analyzed by spectrophotometry and HPLC/RI was incorporated to this thesis. Differences in the content of phenolic substances released from glycosides after acid hydrolysis of samples and differences in saccharide content determined after acid and enzymatic hydrolysis of samples were investigated. Simple sensory analysis of extruded cereal products of different flavour (cocoa, honey, chocolate) was carried out too. In analyzed samples the highest content of total phenolics and total flavonoids was measured in wheat germs. Especially in wheat germs and also in buckwheat and oat flakes, maize brans and cereals products Teddy (cereal balls with cocoa) and Ferda (cereal grains with honey) high levels of individual catechins, phenolic acids and flavonoids were determined too. The quantity of phenolic substances increased for several times in samples processed by acid hydrolysis in comparison to non-hydrolyzed samples. The high content of total saccharides, reduced saccharides and individual mono- and disaccharides was found mainly in extruded products. Concentration of monosaccharides increased in acid hydrolyzed samples in spite of disaccharides concentration that was higher only in some of hydrolyzed samples. In several cases final disaccharide concentrations were lower in hydrolyzed samples than in non-hydrolyzed ones.
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Evaluation of selected dietary supplements - climacterium
Tobolková, Blanka ; Vránová, Dana (referee) ; Zemanová, Jana (advisor)
A dietary supplement is a product that contains nutrients (e.g. vitamins, minerals, herbs, amino acids or fatty acids) intended to supplement the diet. The aim of the diploma thesis was to suggest a prescription for preparation of three types of dietary supplements which are used to reduce of climacteric symptoms, their production and determination of energetic (nutrition) value on account of detected content of proteins, fats and saccharides in dietary supplements. A part of the diploma thesis was to suggest suitable wrapping and price of prepared dietary supplements. The three dietary supplements were used for analyses, namely capsules, herb syrup and herb drops. The content of proteins was determined by Kjeldahl´s method, total fats were determined by Soxhlet extraction and saccharides were determined by titration with potassium permanganate (Bertrand´s method). Dietary supplements in form of capsules were particular analysed on content of heavy metals (lead, cadmium and arsenal). In herbal drops was in addition determined alcohol content (ethanol). There was from the measured data found out, dietary supplement in form of capsules was chosen as the product with the lowest energetic (nutrition) value.
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Analysis of main wine saccharides
Horáková, Hana ; Šabata, Pavel (referee) ; Vespalcová, Milena (advisor)
This diploma thesis deals with determination of carbohydrates in wine. Theoretical part attends to production of wine from grape to treatment and training of wine. It refers saccharides in wine, especially glucose and fructose. The study provides an overview of the available sources concerning the possibilities of determination of carbohydrates in wine by chromatographic methods and Skalar automated chemistry analyser. The study shortly refers simple analytical methods for determination of wine saccharides. The experimental part based on this search deals with analysis of saccharides by high performance liquid chromatography with refractive index detector and UV detector on aminoalkyl column and determination of reducting sugars by Skalar automated chemistry analyser. Finally, the results of these methods were compared.
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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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Comparison of ionisation properties of aetma-labeled saccharides with common labels
Partyka, Jan ; Foret, František
We have tested (2-aminoethyl)trimethylammonium (AETMA) as a label for analysis of oligosaccharides by capillary electrophoresis with electrospray (ESI) mass spectrometry detection and compared its performance to taurine, 2-aminobenzoic acid, 2-aminobenzamide and 8-aminopyrene-1,3,6-trisulfonic acid. The AETMA-labeled saccharides were provided higher ionization signals in positive mode than native sodium or ammonium adducts and equal or higher signals than saccharides labeled by the more commonly used labels tested in this study.
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