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Influence of carbon dioxide elevated concentration on wheat flour quality
Drahovzalová, Kateřina ; Márová, Ivana (referee) ; Hrstka, Miroslav (advisor)
This thesis studied the influence of elevated carbon dioxide concentration on the properties of ears, grain and flour in two varieties of wheat (Triticum aestivum). The Vánek and Septima varieties were grown in special greenhouses, both in normal atmosphere with carbon dioxide concentration (AC = 385 ?mol?mol-1), and at elevated carbon dioxide concentration (EC = 700 ?mol?mol-1). Quantitative analysis of grain (the content of crude protein, starch, moisture and hardness of grain) was carried out using NIR, gluten content (gluten index) was determined after washing with water and gluten quality was expressed as falling number. Total crude protein content was determined according to Kjeldahl, total amino acids and amino acids content by ion exchange chromatography. Variety Vánek showed significantly larger size of the spikes, more grains and higher grain weight, when it was cultivated in the atmosphere of elevated CO2 concentration. For variety Septima, the size of AC and EC ear variants was comparable, but the ears of corn grown in the EC had a significantly greater number of grains and greater weight. Vánek variety grown in elevated CO2 concentration had lower weight of 100 grains, Septima variety grown in elevated CO2 concentration had greater weight of 100 grains. The varieties Vánek and Septima grown at elevated CO2 concentration showed significantly lower content of crude protein (28.4%) and gluten index (by 34.6%). In comparison with the AC variant, EC also showed lower overall content of crude protein and amino acids.
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Innovation of device for mealworms breeding
Dvorský, Adam ; Búran, Martin (referee) ; Adámek, Martin (advisor)
The task of the work was to get familiar to the reader with the possibilities and conditions of edible insect breeding in the Czech Republic, focusing on a selected species of darkling beetle (Tenebrio molitor). Design optimization of breeding conditions for different stages of breeding, with the possibility of accelerating breeding. Another part of the work was to get acquainted with the properties of the microcontroller series Espressif ESP32 and its use in the areas of simple product management. From these identified conditions, a breeding station was designed and gradually implemented in the second half of the work, which was controlled by this microcontroller company Espressif ESP32. The work describes the proposed components for measuring and regulating breeding conditions with a focus on temperature, humidity, food and fluid dosing. The penultimate chapter mentions experimental measurements of regulated conditions with evaluation of measured data. The conclusion is the evaluation of the solution and its other possibilities.
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Modern Approaches in Qualitative Aspects of Foods Assessment
Tobolková, Blanka ; Omelka, Ladislav (referee) ; Rapta, Peter (referee) ; Buňka, František (referee) ; Polovka, Martin (advisor)
Antioxidant properties and some other characteristics of selected organic and conventional products (wine, spelt flours) were evaluated in view of their potential utilization as markers suitable for food unambiguous differentiation according to the affiliation to production system. Beside these, study of fruit juices stability during storage in dependence on different technological procedures of juice processing was performed. In both cases, combination of dominantly EPR and UV/VIS spectroscopy but also other methods (e.g., HPLC, AAS, electrophoresis) was applied to evaluate the stability and antioxidant properties of selected samples. Statistical methods, especially methods of multivariate statistics were used to assess the influence of production and technological-processing operations on antioxidant status of foods and their selected characteristics. Qualitative analysis of Slovak and foreign organic and conventional wines proved that their antioxidant properties are influenced by production system, vintage and variety. On the basis of statistical analysis, descriptors of AAE, kTEMPOL and %RS were selected as the most powerful markers for Slovak organic and conventional wines discrimination. The discrimination of white and red organic and conventional wines possessed 100% and 95.2% correctness, respectively. High correctness of differentiation of Slovak and foreign wines was also achieved. Monitored descriptors of antioxidant activity of spelt flours varied in dependence on season, origin, variety, production system and depend also on way of spelt treatment, although this effect is not so significant. It was also confirmed that the type of extraction agent substantially affects the composition of extracts including polyphenols and flavonoids concentration, affecting thus also their antioxidant activity. Mixture of 50% ethanol/water was selected as the most promising extraction system. Although the results of individual spectroscopic assays revealed high variability and often ambiguous trends, the differences found were sufficient for successful differentiation of both wines and spelt flour samples according to the selected criteria by multivariate statistical processing of the data. Influence of changes in technological procedures of fruit juice processing (nitrogen atmosphere application, utilization of caps with oxygen scavengers) on radical-scavenging properties of 100% pineapples juices with pieces of pineapple and 100% orange juices with pulp was assessed as well. Results obtained proved that antioxidant activity of juices varied in dependence on storage conditions (temperature, storage time, light exposure) and depends also on origin, variety and quality of fruit used. However, the application of nitrogen atmosphere and active packaging materials is not sufficient enough to eliminate the oxidation reactions in juices, but changes in antioxidant activity are better predictable. It can be concluded that EPR spectroscopy could be effectively applied for wines and spelt flours differentiation according to the way of production and to assess the stability of food products, either alone or in combination of UV/VIS spectroscopy and the other methods, utilizing multivariate statistics for processing of experimental data.
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Preparation of rolls with addition of alternative flours
UHLÍŘOVÁ, Lenka
This bachelor thesis is focused on the production of ordinary pastry with the use of alternative flour. Four kinds of crop flour, made from seed pomace of flax (Linum usitatissimum L.), hemp (Cannabis sativa L.), squash (Cucurbita pepo L.) and milk thistle (Silybum marianum L.), were selected. In the literary part of the thesis, common pastry according to legislation, basic and auxiliary raw materials for production and production technology are all de-fined. The crops, from which the addition to wheat flour was processed, are also described. The practical part deals with the production of five types of wheat buns. Four of them are enriched with 5 % of flour made from seed pomace of the four mentioned crops. Production of buns was followed by sensory evaluation according to the descriptors. Weight lost by baking, the quantity of polyphenolic substances and antioxidant activity were also evaluated.
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Evaluation of hemp protein flours stability
NĚMCOVÁ, Hana
The aim of this diploma thesis is to explore the possibility of storage of hemp protein concentrates extracted by mechanical sifting of milled hemp (Cannabis sativa) seed cake. On the ground of previously acquired scientific knowledge two size fractions of hemp flour were prepared - protein flour containing particles lower than 180 m and fibre flour containing particles larger than 180 m. The two types of flours were subsequently stored for the period of eight months in different conditions. On the stored samples and on the samples before the attempted experience were evaluated following parameters: dry matter, fat content, titratable acidity, antioxidant activity and polyphenol content. The diploma thesis found out the evaluated parameters are statistically significantly affected by the flour's fraction. The type of storage has statistically significant effect on all the parameters, except of the antioxidant activity. The analysis showed that the storage is less suitable for fraction containing less than 180 m because the fraction containing particles less than 180 m is more likely to go rancid given to the larger fat content, shows lower antioxidant activity, contains less polyphenols and tends to become moister. Better outcomes were showed by samples stored in vacuum, of which samples stored at a temperature of 5 °C showed even better results. These samples revealed lower fat dissociation, lower acidity and higher antioxidant activity. However, 9 % moisture that could lead to higher microbial strain was observed.
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Innovation of device for mealworms breeding
Dvorský, Adam ; Búran, Martin (referee) ; Adámek, Martin (advisor)
The task of the work was to get familiar to the reader with the possibilities and conditions of edible insect breeding in the Czech Republic, focusing on a selected species of darkling beetle (Tenebrio molitor). Design optimization of breeding conditions for different stages of breeding, with the possibility of accelerating breeding. Another part of the work was to get acquainted with the properties of the microcontroller series Espressif ESP32 and its use in the areas of simple product management. From these identified conditions, a breeding station was designed and gradually implemented in the second half of the work, which was controlled by this microcontroller company Espressif ESP32. The work describes the proposed components for measuring and regulating breeding conditions with a focus on temperature, humidity, food and fluid dosing. The penultimate chapter mentions experimental measurements of regulated conditions with evaluation of measured data. The conclusion is the evaluation of the solution and its other possibilities.
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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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Protein composition of flours and bakery products
Rychlovská, Kristýna ; Čapek Adamec, Martin (advisor) ; Hynek, Radovan (referee)
The aim of this study was to carry out an analysis of a protein composition of diferent crop species using the method of peptide mass mapping. The samples were analysed using analytical method LC/ESI-Q-TOF and the acquired spectra were compared with the plant protein databases. The origin of the found plants was discussed in the aspect of the reliability of the used method considering the taxonomical relationships in the taxonomical group. The results of the analysis were compared with the food composition specified by the producer, and it was evaluated, if it is possible to verify the protein composition by using the applied method. In case of maize (Zea mays) this method is considered as reliable, because all of the found proteins were indentified as maize proteins. In case of rice (Oryza sativa) and pea (Pisum sativum), only one, respectively, two proteins of different plants species were found in the number of the relevant plant proteins. This method was evaluated as not so reliable for samples made of cereals (Poaceae). It is possible to conclude, whether the product comes from Poaceae or not, but it is impossible to verify the taxon of genus or the inferior taxons. This fact was in a great extent disscused in this thesis - the reason is probably the resemblance of Poaceae, and the...
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Modern Approaches in Qualitative Aspects of Foods Assessment
Tobolková, Blanka ; Omelka, Ladislav (referee) ; Rapta, Peter (referee) ; Buňka, František (referee) ; Polovka, Martin (advisor)
Antioxidant properties and some other characteristics of selected organic and conventional products (wine, spelt flours) were evaluated in view of their potential utilization as markers suitable for food unambiguous differentiation according to the affiliation to production system. Beside these, study of fruit juices stability during storage in dependence on different technological procedures of juice processing was performed. In both cases, combination of dominantly EPR and UV/VIS spectroscopy but also other methods (e.g., HPLC, AAS, electrophoresis) was applied to evaluate the stability and antioxidant properties of selected samples. Statistical methods, especially methods of multivariate statistics were used to assess the influence of production and technological-processing operations on antioxidant status of foods and their selected characteristics. Qualitative analysis of Slovak and foreign organic and conventional wines proved that their antioxidant properties are influenced by production system, vintage and variety. On the basis of statistical analysis, descriptors of AAE, kTEMPOL and %RS were selected as the most powerful markers for Slovak organic and conventional wines discrimination. The discrimination of white and red organic and conventional wines possessed 100% and 95.2% correctness, respectively. High correctness of differentiation of Slovak and foreign wines was also achieved. Monitored descriptors of antioxidant activity of spelt flours varied in dependence on season, origin, variety, production system and depend also on way of spelt treatment, although this effect is not so significant. It was also confirmed that the type of extraction agent substantially affects the composition of extracts including polyphenols and flavonoids concentration, affecting thus also their antioxidant activity. Mixture of 50% ethanol/water was selected as the most promising extraction system. Although the results of individual spectroscopic assays revealed high variability and often ambiguous trends, the differences found were sufficient for successful differentiation of both wines and spelt flour samples according to the selected criteria by multivariate statistical processing of the data. Influence of changes in technological procedures of fruit juice processing (nitrogen atmosphere application, utilization of caps with oxygen scavengers) on radical-scavenging properties of 100% pineapples juices with pieces of pineapple and 100% orange juices with pulp was assessed as well. Results obtained proved that antioxidant activity of juices varied in dependence on storage conditions (temperature, storage time, light exposure) and depends also on origin, variety and quality of fruit used. However, the application of nitrogen atmosphere and active packaging materials is not sufficient enough to eliminate the oxidation reactions in juices, but changes in antioxidant activity are better predictable. It can be concluded that EPR spectroscopy could be effectively applied for wines and spelt flours differentiation according to the way of production and to assess the stability of food products, either alone or in combination of UV/VIS spectroscopy and the other methods, utilizing multivariate statistics for processing of experimental data.
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Influence of carbon dioxide elevated concentration on wheat flour quality
Drahovzalová, Kateřina ; Márová, Ivana (referee) ; Hrstka, Miroslav (advisor)
This thesis studied the influence of elevated carbon dioxide concentration on the properties of ears, grain and flour in two varieties of wheat (Triticum aestivum). The Vánek and Septima varieties were grown in special greenhouses, both in normal atmosphere with carbon dioxide concentration (AC = 385 ?mol?mol-1), and at elevated carbon dioxide concentration (EC = 700 ?mol?mol-1). Quantitative analysis of grain (the content of crude protein, starch, moisture and hardness of grain) was carried out using NIR, gluten content (gluten index) was determined after washing with water and gluten quality was expressed as falling number. Total crude protein content was determined according to Kjeldahl, total amino acids and amino acids content by ion exchange chromatography. Variety Vánek showed significantly larger size of the spikes, more grains and higher grain weight, when it was cultivated in the atmosphere of elevated CO2 concentration. For variety Septima, the size of AC and EC ear variants was comparable, but the ears of corn grown in the EC had a significantly greater number of grains and greater weight. Vánek variety grown in elevated CO2 concentration had lower weight of 100 grains, Septima variety grown in elevated CO2 concentration had greater weight of 100 grains. The varieties Vánek and Septima grown at elevated CO2 concentration showed significantly lower content of crude protein (28.4%) and gluten index (by 34.6%). In comparison with the AC variant, EC also showed lower overall content of crude protein and amino acids.
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