National Repository of Grey Literature 67 records found  1 - 10nextend  jump to record: Search took 0.05 seconds. 
Development of cereal products for specific nutrition with the addition of legumes, algae and yeasts
Pavlištíková, Nela ; Mikulíková, Renata (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on the development of cereal products for special nutrition with the addition of legumes, algae and yeast. In the theoretical part, expert knowledge about gluten-free cereals, their chemical composition, gluten and food fortification is developed. Then an overview of the legumes, algae and yeasts tested in this work was elaborated. As a part of the literature review, emphasis was placed on the chemical composition of the analysed products. In the experimental part, the characterization of selected gluten-free cereals and legumes was carried out. The tested cereals were buckwheat, quinoa and gluten-free oatmeal. Pea, red lentil and Beluga black lentil were selected from among legumes. Furthermore, various types of algae and yeast extracts were prepared, which were subsequently optimized. Algae of the genera Dulse, Chlorella and Spirulina were selected for enrichment of pseudocereals. Dried baker's yeast and Saccharomyces cerevisiae were chosen as yeast representatives. Phenolics, flavonoids, antioxidant activity, carbohydrates, proteins, fatty acids, lipids and lipophilic pigments were determined in gluten-free cereals and legumes. The content of -glucans and gluten were determined for in cereals as well. Some content of phenolic substances, flavonoids, antioxidants, total fatty acids, lipophilic substances, pigments and -glucans were found in extracts from algae and yeast. Selected samples were also subjected to antimicrobial and cytotoxicity tests. Finally, mixed cereal products were prepared from selected gluten-free cereals, legumes, selected algae and yeast extracts and algae biomass. Extracts were selected based on obtained results and subjected to MTT cytotoxicity tests. It was found that the addition of pea, extracts from algae and yeast or the algae biomass itself increased the protein content of the prepared mixtures. Furthermore, in hexane:ethanol extracts from Chlorella and Spirulina or their biomass, the amount of antioxidants has been increased. The obtained results show that the combination of cereals with addition of algae and yeast extracts is suitable for increasing the protein content in gluten-free products. It was also found that selected microalgae and yeast have the potential to enrich gluten-free products with bioactive substances, when using biomass or extracts produced from them.
Obilniny ve výuce geografie zemědělství
DOČEKAL, Lukáš
The aim of the bachelor thesis is to create teaching texts for teaching the geography of cereals, namely for teaching at universities, upper-secondary schools and elementary schools. First, the individual cereals grown in the world are presented in detail - their botanical and morphological characteristics, their origin, development and breeding, followed by a description of the use of cereal products, the characteristics of natural conditions and agro-techniques of cereals and the geographical distribution of cereals in the world. Part of the bachelor's thesis is also an analysis of university, upper-secondary and elementary school textbooks containing the subject of the geography of agriculture, which are subsequently used in the creation of teaching texts. Tables, maps and extensive literature are part of the bachelor thesis.
Production and characterization of protein isolates from different kinds of bran
Vybíral, Lukáš ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis deals with the use of various types of bran as a by-product in the milling of cereals. Mills create a huge amount of this material per year. The most common way of processing bran is mostly incineration and to a lesser extent it is used as feed for livestock. Depending on the type of cereal, bran contains 10-20% of protein, which disappears from the food chain due to combustion. Within the framework of sustainability and valorisation of waste, which has recently been largely discussed, great emphasis is placed on waste minimization whether in the field of its production or further processing. Due to the relatively high protein content, bran appears to be a suitable starting material to produce protein supplements. Proteins can be extracted from bran based on their different solubility at different pH. In the alkaline method, the proteins are first dissolved in an alkaline pH and then precipitated in an acidic medium. Lyophilization is followed by characterization of the extract in terms of yield, protein content, moisture, amino acid profile and digestibility. The highest yield was obtained with the oat bran isolate (13,5 ± 0,6 g of isolate per 100 g of bran). In terms of protein content, the best protein isolate was also obtained from oat bran (95,2 ± 0,4% protein in the isolate). Another determination was the analysis of the amino acid profile, in which a high content of arginine was found in all analyzed protein isolates from bran. Determination of digestibility showed very good digestibility of all produced protein extracts from bran.
Analysis of selected biologically active substances in cereal products
Skutek, Miroslav ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Presented diploma thesis was focused on study of biologically active compounds, especially some sugars in cereal products. In experimental part the total of 29 different cereal materials, food industry waste products and natural complex matrixes (microbial polysaccharide, honey, beer) were used. As a part of this work optimization of analytical methods suitable for analysis of simple sugars, oligo- and polysaccharides was done. In cereal samples reduced and neutral sugars were analyzed spectrophotometrically and individual sugars were detected by chromatography. For HPLC/RI analysis optimal mobile phase composition and chromatography conditions were proposed. For mono- a oligosaccharides C18-NH2 sorbent, mixture acetonitril:water 75:25 as mobile phase and flow 1 ml/min were verified as suitable separation parameters. Thin layer chromatography of mono- and oligosaccharides was optimized too. Introduced chromatography and spectrophotometry methods were then applied to analysis of cereal samples. As a model sugar natural microbial polysaccharide pullulan was used to analytical method testing. In cereal products and food matrixes total neutral and reduced sugars as well as products of their acid and enzyme hydrolysis were measured. Detailed analysis of some glycoside composition was tested too. As the most usable method for both qualitative and quantitative analysis of cereal sugars HPLC/RI method was found. To detailed identification of malto-oligosacharides tandem LC/MS/MS technique using derivatization by 1-phenyl-3-methyl-5-pyrazolon was tested too.
Determination of forces effect and stress check of frame of crushing mill of grain S 1200
Pernica, Jiří ; Kovář, Stanislav (referee) ; Škopán, Miroslav (advisor)
This thesis is focused on determination of the power effects, strength calculation and following optimalization of the box for grain roller mill S 1200 – the prototype of the mill to be produced by the copany ROmiLL, s. r. o. Besides issues mentioned above there ar also stated roller mills worldwide trends as well as results and evaluation of the calculations together witu optimalization of roller mill box.
Cereals - Active Substances, Biological Effects and Selected Applications in Food Industry
Lichnová, Andrea ; Tremlová, Bohuslava (referee) ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
The presented doctoral thesis is focused on the study of the biological effects of active compounds found in cereals, on the development of methods of analysis these effects, on the determination of the content of active substances and characterization of the relationship between composition and biological effects of cereals and cereal products. For the analysis several kinds of raw cereal samples (flakes, flour, germ, bran), flavored extruded cereal products and also samples of paddy and husked rice were chosen. To major types of analysed active compounds belong mainly phenolic compounds in the form of glycosides and aglycones, and also saccharides. Group parameters such as total polyphenols, flavonoids and total and reducing saccharides were determined spectrophotometrically, individual phenolics and saccharides were determined by high performance liquid chromatography (HPLC). TEAC, DPPH and CLAMS methods were used to determine the antioxidant activity. Indirect methods of determination of substances with antioxidant effect were used as well. Results of the total antioxidant activity were compared with values of antimutagenic/genotoxic activity obtained by several microbial test systems. Antimutagenic effect was expressed as a percentage of inhibition of effect of standard mutagen and could be considered as a potential preventive effect of cereals to DNA arising primarily by free radicals effect. The highest values of group and individual phenolics, antioxidant and antimutagenic activity were found in germs, bran, in buckwheat products and in coloured and raw rice. In flavoured cereal products addition of chocolate or fruit positively influences content of active phenolic substances as well as sugars, antixidant and antimutagenic activity. In a representative sample of Czech population, questionnairy study was performed to monitor interest in cereals and consumer preferences. The most of consumers consider cereals with chocolate flavour as less healthy than confirmed results of laboratory analyses. In this study some new food products were developed. Several types of model cereal products containing plant (fruit, vegetables) extracts were proposed. Extracts were added to cereals in freeze-dried and encapsulated form. The highest positive effect exhibited addition of local forrest fruit extract. Within preparation of encapsulated extracts several methods of preparing lipid or saccharides particles were also tested. The encapsulation efficiency of the methods and stability and size of particles were analysed. Optimal type of fortified cereal foods could be suggested based on the acquired results. Selected cereals were used as alternative carbon substrates (processed or raw) for the cultivation of microorganisms to produce enriched biomass usable in the feed industry. We can conclude that cereals in raw as well as processed form belong to universal foods and rich sources of biologically active substances. They can be processed by many ways. They can be used for direct consumption, as a part of new products and also undirectly as a substrate for feedstock.
Monitoring of cereal products uptake in a sample of Czech population
Vlachová, Martina ; Hurtová, Jana (referee) ; Márová, Ivana (advisor)
This bachelor’s thesis was focused on monitoring of consumption of cereal products and analysis of some of their active components. In theoretical part an overwiev of cereals and their composition was introduced. In experimental part a set of analytical parameters was obtained in selected cereal products: total phenolics, total flavonoids and antioxidant activity. The highest level of these active substances was detected in products containing chocolate and forest fruit. Further, 161 completed consumer questionnaires were collected. From these data common knowledge in consumers, their shopping conventions and individual products preferences were evaluated.
Monitoring of vitamin E content in the samples of cereals
Cibulcová, Pavla ; Borkovcová,, Ivana (referee) ; Benešová, Karolína (advisor)
Thesis deals with the analysis of vitamin E in cereal samples, namely barley and wheat and malt produced from them. Selected samples were treated with low-temperature plasma, fungicide and biological treatment to elimination fungus and mycotoxins. The aim of the thesis was to find out the influence of the treatment, the combination of several types of treatment on vitamin E content in grain and malt. If the content of health-positive substances is not reduced and grain can be used for food, malt, or for feed purposes. The theoretical part focuses on the properties, occurrence, biochemistry and importance of vitamin E for living organisms. It also focuses on the properties of cereals that are a significant source of vitamin E. Malt production and sample treatment are also described. The experimental part describes the field experiment, individual types of treatment, extraction of vitamin E from the samples and determination of vitamin E content by high performance liquid chromatography with fluorescence detection. The results are compared with the current literature. It was found that the treatment did not have a significant negative effect on vitamin E content.
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.
Analysis of glucans in plant and microbial samples
Vít, Radek ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The aim of the diploma thesis is study of glucans production in selected species of yeasts, algae and plants. Cultivation conditions for yeast strains were performed to gain increased production of glucans under different temperature conditions and in media of different composition. Into the set of tested yeasts species strains Saccharomyces cerevisiae (CCY 6646), Sporidiobolus pararoseus (CCY 19-9-6), Phaffia rhodozyma (CCY 77-1), Rhodotorula glutinis (CCY 20-78-26) and Cystofilobasidium infirmominiatum (CCY 17-18-4) were enrolled. Saccharomyces cerevisiae was cultivated as a control strain because of its verified production of -glucans. -glucans were determinated by the enzyme kit K-YBGL Megazyme. For comparison, algal strain Euglena gracilis (CCALA 349), some species of mushrooms (shiitake, oyster mushroom, garden champignon and Jew’s ear) and cereals (wheat, rye, oats, rice and barley) were analysed too. Further, fatty acid content in the yeast cells was determined by the GC/FID. The best producer of yeast -glucans was R. glutinis CCY 20-7-26, which showed the highest biomass production (12-14 g/l) and also a relatively high amount of -glucans (25-30 %), in cultivation at 15 °C in a medium containing yeast extract in combination with ammonium sulphate. The presence of -glucans has been demonstrated in the microalgae, Euglena gracilis CCALA 349, as well as in samples of higher fungi and cereals.

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