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Analysis of biologically active substances in some cereal products
Valentová, Radka ; Starečková, Terezie (referee) ; Márová, Ivana (advisor)
Presented bachelor thesis is focused on study of biologically active substances in cereal products. In theoretical part over view of cereal active substances, predominantly phenolic compounds were introduced. In practical part 15 kinds of cereal products were analyzed. In these materials some group parameters - total phenolics, total flavonoids and total antioxidant activity were measured by spectrophotometry. RP-HPLC/UV-VIS method was performed for analysis of selected individual flavonids. The highest content of phenolic compounds was measured in cereals containing fruits (raspberries, blueberries, tropical and red fruit), cacao, crusty fruits (hazel nuts, sunflower seeds) and buckwheat. All cereal products contain catechine, epicatechine, catechin gallate, epicatechin gallate, chlorogenic and ferulic acid. As a part of bachelor thesis simple sensory analysis was performed and consumer questionnaires were evaluated.
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Fortification of selected cereal products
Hurtová, Jana ; RNDr.Renata Mikulíková, Ph.D. (referee) ; Márová, Ivana (advisor)
Present diploma thesis describes the study of bioactive compounds in the cereals. The work is focused on possible fortification of cereal products in order to increase nutritional value of final products which is reduced during the food processing and storage. Cereal grains are rich in several phenolic compounds, vitamins and minerals that reduce the risk of chronic diseases. The aim of this study was the preparation and analysis of model fortified cereals using lyophilized fruit originating from Czech Republic. A comparative analysis of content of bioactive substances in commercial and fortified products for children was performed too. The experimental part deals with a content of individual flavonoids by RP-HPLC/UV/VIS method, spectrophotometric determination of total and reducing saccharides and analysis of mono- and disaccharides by the HPLC/RI method as well. Differences in the content of individual flavonoids and saccharides after the application of acid hydrolysis of samples were investigated. The content of these compounds increased in most products because of their release from glycosidic forms. Presence of phenolics was confirmed in all analyzed cereals. Addition of 10% of lyophilized fruit/vegetable preparative (carrot, berries, apples) caused several fold increase of phenolics content in model mixtures. In commercially available cereal products there are relatively high differences in total phenolics content, proportionally to fruit component amount. The work included the spectrophotometric analysis of total polyphenols and flavonoids in a model physiological environment (artificial stomach juice) in which the hydrolysis of bound phenolic compounds occurred. The results of this study show that addition of lyophilized fruit seems to be a good way to increase the nutritional value and maintain the content of bioactive compounds in cereal products.
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Možnosti využití sladu pro sportovní výživu
Mišúnová, Lucie
The diploma thesis on “Possibilities of using malts for sports nutrition“is focused on the production of malts and their use in sports supplements. The theoretical part is devoted to individual cereals and pseudocereals, their nutritional composition, individual nutri-ents and their importance in nutrition and some possible products for sports nutrition. The practical part includes the production of single malts from selected cereals and pseudocereals and the production of experimental products that could have applications in sports nutrition. The products were then analysed for sensory analysis and nutritional value was determined.
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Development of fortified gluten-free cereals for specific nutrition
Dohnalová, Radka ; Fialová, Lenka (referee) ; Márová, Ivana (advisor)
The bachelor thesis was focused on the development of enriched gluten-free cereals for special nutrition. The fortified cereal product included processed microbial biomass, either as a freeze-dried powder or as an extract, for which the phenolic content, antioxidant content and protein content were determined. The theoretical part includes findings from professional literature on gluten-free cereals, pseudocereals and their chemical composition. Subsequently, a review on microalgae and yeasts was prepared including a list of their metabolites. The literature search focused on green microalgae and carotenogenic yeasts. In the experimental part, the characterization of the selected pseudocereals and optimization of the prepared extracts of the selected microalgae and carotenogenic yeast were firstly carried out. The selected pseudocereals were amaranth, buckwheat and quinoa. The green microalgae strain Chlamydomonas reinhardtii and the carotenogenic yeast strain Cystofilobasidium macerans were selected for enrichment of the pseudocereals. Carbohydrates, proteins, fatty acids, -glucans, gluten, vitamins, phenolic substances, flavonoids and antioxidants were determined in the pseudocereals. Total fatty acids, lipophilic substances, phenolic substances and total antioxidant activity were detected in the microbial biomass. Finally, mixed cereal products were prepared from pseudocereal flour, microbial biomass and microbial extract. The cytotoxicity of the selected extracts was determined by MTT assay. It was found that the addition of algal biomass alone or algal extract to cereal flours resulted in a significant increase in protein. The yeast ethanol extract increased the phenolic and antioxidant content of the cereal products.
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Development of cereal products for special nutrition with addition of yeast and algae extracts
Požgayová, Viktória ; Fialová, Lenka (referee) ; Márová, Ivana (advisor)
This diploma thesis focuses on the development of gluten-free cereal products enriched with yeast and algae extracts. The theoretical part of this thesis was focused on gluten-free cereals used in the experimental part, on microbial biologically active substances and on the possibility of their use in the food industry. A chapter devoted to the evaluation of food safety and additives in food industry was also included in this part. The theoretical part concludes with the description of the methods used to analyses of selected biologically active substances in the samples. In the experimental part of this thesis, three samples of gluten-free flours were analysed, i.e. flour labelled as gluten-free, corn flour and rice flour. The content of total saccharides, proteins, gluten, lipids and bioactive substances such as phenolic substances, flavonoids, antioxidants and ß-glucans were analysed in the samples. In the most of the tested parameters corn flour achieved the best results. In order to prepare the microbial extracts, commercially obtained biomass of Spirulina and Chlorella and cultivated biomass of carotenogenic yeasts Rhodosporidium toruloides and Rhodotorula kratochvilovae were used. The extracts were prepared using solvents labelled as GRAS (water, 96 % ethanol, hexane and their combinations). Lipids, proteins and active substances such as pigments, phenolic substances, antioxidants, vitamins and ß-glucans were analysed in the prepared extracts and biomass. Spirulina and Chlorella extracts showed higher concentrations of bioactive substances while yeast extracts contained higher concentration of carotenoids, lipophilic provitamins and ß-glucans. The safety of prepared extracts used in food applications was verified by the MTT test of cytotoxicity. None of the tested extracts showed cytotoxic effects. In order to prepare enriched cereal products, the corn flour, biomass of Spirulina, aqueous extract of Spirulina, ethanolic extract of R. toruloides and the combination of Spirulina biomass and R. toruloides extract were chosen based on the obtained results. Two types of enriched cereal products were prepared and in enriched products the increase of antioxidant activity, phenolic compounds and protein content was detected.
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Porovnání vybrané sklízecí mlátičky v konvenčním zemědělství a v precizním zemědělství.
VALENTA, Pavel
The diploma thesis on the comparison of the harvest of cereals using the combine harvester in the quality of work is based on the technical literature review, which describes the individual parts of the combine harvester from the harvesting adapters to the threshing device. The methodology of this diploma thesis describes the procedure by which the results and values for the comparison of the Class Lexion 770 TT combine when working in manual control and GPS control (Global Positioning System). Measured, calculated and compared values obtained according to the 2019 methodology. Harvesting of grain crops using the combine harvester is compared in terms of harvest efficiency, harvest losses, machine throughput, performance balance and fuel consumption. The thesis also includes basic economic operating costs.
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Cereal pests and their natural enemies
Honěk, Alois ; Martinková, Zdena ; Platková, Hana ; Saska, Pavel ; Skuhrovec, Jiří
The methodology mainly summarizes the new results and experiences of the author's team, which has been studying the biology of some cereal pests and their natural enemies for a long time. The aim is to draw attention to selected species of pests, to provide instructions on how to recognize them, in some cases to find out their current numbers in cereal stands and within the possibilities of current knowledge to predict further development of their abundance in a given stand and estimate yield reduction. Another goal is to recapitulate protection options with an emphasis on the use of natural enemies. The third goal is enlightenment. The methodology provides an accessible way to understand the biology and population development processes of cereal pests (especially aphids) so that the reader does not remain a blind user of unwarranted practical instructions, but can decide for himself according to the immediate situation.
Fulltext:  PDF
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Morphological, physiological and proteomic changes of cereals under abiotic stress
Kantová, Anežka ; Vítámvás, Pavel (advisor) ; Hnilička, František (referee)
Cereals are among the oldest crops that have been grown and used by humans as important component of their diet. It is an important source of livelihood for the human population and have a wide range of uses, mainly in the food industry. Cereals generally serve as a source of energy in the diet, due to the high starch content. The most commonly grown types of cereals are especially wheat, barley, rye, rice, corn, but there may be other species such as oats and millet. However, even cereals do not avoid the problems associated with the action of abiotic stress factors. Their effect on all plants is manifested by a decrease in vitality, but in crops - such as cereals - mainly by a decrease in yield. Due to the reduction in yield, breeding of resistant cereal genotypes is now in the primary interest of breeders. This work summarizes the basic principles of the action of abiotic stress on plants and explains the reactions of various types of cereals to abiotic stress factors. Key words: proteome, physiology, cereals, abiotic stress, yield
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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.
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Physiological changes of cereals under temperature stress
Kantová, Anežka ; Vítámvás, Pavel (advisor) ; Hnilička, František (referee)
Cereals are among the oldest crops that have been grown and used by humans as important component of their diet. It is an important source of livelihood for the human population and have a wide range of uses, mainly in the food industry. Cereals generally serve as a source of energy in the diet, due to the high starch content. The most commonly grown types of cereals are especially wheat, barley, rye, rice, corn, but there may be other species such as oats and millet. However, even cereals do not avoid the problems associated with the action of abiotic stress factors. Their effect on all plants is manifested by a decrease in vitality, but in crops - such as cereals - mainly by a decrease in yield. Due to the reduction in yield, breeding of resistant cereal genotypes is now in the primary interest of breeders. This work summarizes the basic principles of the action of heat/cold stress on plants and explains the reactions of various types of cereals to these abiotic stress factors. Key words: proteome, physiology, cereals, temperature stres, yield, abiotic stres
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