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Characterization of waste rice substrates and their potential utilization by microorganisms
Kapar, Jiří ; Duroňová, Kateřina (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis was to characterize some cereal substrates. Based on the results of group parameters the most suitable substrate for cultivation of model industrial microorganisms was proposed. Analysis of total phenolics, reducing sugars and total sugars was performed spectrophotometrically. Using high-performance liquid chromatography with refractometry index detection content of individual mono-and disaccharides was measured. Saccharides were extracted from cereal substrates by water and then acid hydrolysis was applied. Two rice substrates were then used as nutrition sources for cultivation of two model industrial microorganisms: yeast Rhodotorula glutinis and bacterium Bacillus subtilis. Before use to production media substrates were processed by chemical and enzyme hydrolysis and analyzed. Production of microbial biomass in media with modified waste substrates was evaluated.
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Analysis of some active substances in different products from rice
Valentová, Radka ; Melounová, Jitka (referee) ; Márová, Ivana (advisor)
Presented diploma thesis is focused on analysis of selected biologically active substances in different kinds of natural and peeled rice. In rice samples phenolic compounds, antioxidant activity, content of saccharides and vitamin C were analysed. Active substances and saccharides were analysed by UV-VIS spectrophotometry and RP-HPLC-UV/VIS. Content of phenolic compounds and saccharides was measured before and after acid hydrolysis. The content of these compounds increased several times because of release of active substances from glycosides. As a part of diploma thesis basic sensory analysis was performed and consumer questionnaires were evaluated. The highest level of antioxidant activity was detected in Indian Wild rice. The highest content of total polyphenols and flavonoids was detected in Red Rice Natural before acid hydrolysis. After acid hydrolysis the highest content was detected in Indian Wild rice. The highest content of individual flavonoids, phenolic acids and catechins was detected in natural rice Indian Wild, Rice Three colours and in two samples of rice parboiled. The highest content of total and reducing saccharides was found in rice Indian Wild before hydrolysis, while after hydrolysis the content was very similar in all rice samples. The amount of individual monosaccharides after acid hydrolysis increased, while total content of disaccharides decreased. The highest value of simple sugars was detected in rice parboiled and Indian Wild rice. The content of vitamin C was detected only in four rice kinds - in two samples of rice parboiled, Rice Three colours and rice Indian Wild.
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Potential of genetic engineering for breeding plants tolerant to abiotic stresses: cold resistance in rice
Lotová, Gabriela ; Lipavská, Helena (advisor) ; Janská, Anna (referee)
With increasing population and climate change, there has been an increase in efforts to breed more efficient crops. Genetic engineering has opened unprecedented breeding possibilities in developing plants with desired traits. Transgenic crops with better qualities, including resistance to adverse environmental conditions, can contribute to solving problems of hunger and malnutrition in developing countries. Although society perceives genetically modified crops rather negatively, these crops are widely used as feed for livestock and outside Europe also for human nutrition. Because of the complexity of resistance to abiotic stress, the utility of genetic manipulations for the breeding of resistant plants was previously not anticipated. However, it turned out that modification of the stress signalling cascade or transcription factors can lead to success. This thesis summarizes the possibilities of genetic modification of crops, which may result in better tolerance to cold, and is mainly focused on rice. Part of the work deals with transduction of cold signal, whose modification can also result in increased tolerance to cold. Another part deals with transcription factors that activate expression of low temperature- resistant genes. The greatest attention is paid to CBF/DREB transcription factors that...
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Využití netradičních druhů obilovin pro výrobu běžného pečiva
Siudová, Dominika
The aim of the thesis The usage of non-traditional cereals in baking production was to determine the influence of the addition of flours made from unusual kinds of cereals on the quality of baking products. The theoretical part deals with ingredients and the technologies used in bread production and the description, material composition, properties and usage of unconventional cereals such as sorghum, corn, rice and Job's tears. The practical part is focused on the production of baguettes with the addition of flour from these cereals. The quality of the final baguettes was assessed by measuring the volume, firmness of packed and unpacked product during the first and the second day of storage. In addition, the colour of bread was measured and the sensory quality was evaluated. The addition of 5,5 % of these flours into the product did not have a significant negative effect on bread volume, its firmness and sensory properties. Although bread gained interesting colour and its nutritional value has raised up.
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Rýže jako surovina a její využití v cereálních technologiích
Jurečková, Eliška
This work is focused on rice as an ingredient, as well as its usage in cereal technology. It describes the history of rice growing, characterises rice from the botanical point of view and describes its chemical composition. Furthermore this work focuses on rice processing for the use in food industry and partucular rice cereal products. The conclus-sion is devoted to sensory evaluation of home-made rice flour buiscuits.
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Využití rýže v potravinářství
Lustigová, Zuzana
The bachelor thesis “The usage of rice in the food industry“ is divided into three parts. The first part describes morphological and anatomical structure, the conditions and the methods of growing, production, consumption and import of rice to the Czech Republic. The second part focuses on the chemical composition of the grain, the subsequent pro-cessing, rice species and the rice products. The sensory questionnaire was created in the last practical part and six rice species were evaluated graphically according to him. The best was the arborio rice and the worst wild rice.
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Vývoj komoditní vertikály rýže v Thajsku
Hykšová, Markéta
The bachelor thesis focuses on the development of the commodity chain of rice in Thailand. The literature review is generally defining an agrarian market, also with its individual types. The bachelor thesis then describes basic characteristics of the current agribusiness environment, rice commodity chain, general characteristics of cereal crops, with a closer focus on rice. The analytical part of the thesis is defining the world major rice production area. Afterward, the analytic part is dealing with the main global commodity flow in the study area, which is then compared with the main selected global production centers. Based on the analysis it is possible to specify the position of Thailand on the World rice market.
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Evaluation of functional properties of selected vegetable flours
VÍTKOVÁ, Věra
This bachelor thesis deals with basic structure, nutritional properties, production and use of flours. There are information about cereals and legumes, which are used for productions of flours. This thesis talks about food intolerances, which can be a reason why change basic flours of wheat, barley, oat and rye to another. Practical part is about 14 flours, which were tested on dry matter, humidity, nitrogen substances content, proteins, protein electrophoretic profiles (patterns), solubility, water and fat holding capacity, formation of gels and changes of colours during a boiling. The results of this research are information about nutrition and functional properties of tested flours.
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Senzorické hodnocení vybraných obilných nápojů
URBAN, Martin
The aim of this diploma thesis was a sensory and nutritional evaluation of vegetable drinks. The analysis focused on rice and oat drink. Part of the population has health problems with milk consumption. Some substitutes can be beverages from legumes, cereals, nuts, etc. Oat and rice drinks does not contain cholesterol, are a source of minerals and vitamins. Rice and oat drink does not contain lactose or milk proteins. The downside is the insufficient amount of protein and the fact that, unlike milk protein, the protein of cereals is poor, deficient. Rice drink does not contain gluten. The sensory analysis aimed to compare individual drinks and determine their differences between samples, to determine the intensity of certain properties and to rank the samples from best to worst. The sensory analysis confirmed the differences between manufacturers. In the case of rice beverages, the evaluators concluded that they perceived the difference between the product of Alpro and Alnatura, with the Alnatura drink being considered the most acceptable. The amount of fat in rice beverages was low (1-1.1 g fat per 100 ml). Drinks also contain little protein (0.1-0.3 g / 100 ml). Oat beverages differed in particular with Alnatura and Delhaize - Bio. The evaluators preferred Delhaize Drink Company - Bio the most. The nutritional composition of the fat-like products is similar to rice beverages (1-1.5 g fat per 100 ml). The amount of protein was slightly higher (0.6-1 g protein per 100 ml). From a nutritional point of view, there is a noticeable difference between cow's milk and oat and rice beverages. The rice and oat drinks that were preferred contained the most sugar and the brewing flavor was the least noticeable.
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