|
|
Evaluation of the selected biological, production and processing properties of Jerusalem artichoke
ZIKMUNDA, Jan
The diploma thesis is focused on the evaluation of selected biological, production and processing properties of Jerusalem artichoke tubers. For this purpose, a trial was established in the spring of 2021 in the locality Valečov situated in the district Havlíčkův Brod. Four varieties of Jerusalem artichoke were involved into the trial - Karin, Rút, Skarlet and Zlata. The varieties were grown in three variants. Individual cultivation operations, gradual plant growth and tuber harvest were recorded. For all varieties following parameters were evaluated: tuber yield, mean number of tu-bers per plant, mean tuber weight, tuber dry matter content, inulin content in fresh matter, inulin content in dry matter. The variety Rút achieved five best results in the six studied parameters: yield of 42.6 t/ha, tuber weight of 45.30 g, tuber dry matter content of 32.71 %, inulin content in fresh matter of 16.02 %, inulin content in dry matter of 49.06 %. Dry matter content of harvested tubers was measured. Jerusalem artichoke flour and semolina were produced from dry matter. Jerusalem artichoke flour or semolina replaced a half of a third of common flour in eight food products that were subjected to sensory evaluation.
|
|
|
Corelation of transport and viscoelastic properties of hydrogels with diffusion gradient
Ščotková, Romana ; Sedláček, Petr (referee) ; Smilek, Jiří (advisor)
The aim of the presented bachelor thesis was to prepare hydrogels with diffusion gradient and to demonstrate the gradient structure of hydrogels in terms of viscoelastic and transport properties. With regard to potential biomedical applications, the cationic polysaccharide chitosan was selected for the preparation, especially for its antimicrobial and biocompatible properties. The resulting gradient hydrogels were subsequently characterized by oscillation tests to observe the differences using different concentrations and molecular weights of chitosan, crosslinking agent concentrations, dispersion environments for chitosan dissolution, and different gel crosslinking times. The samples were also subjected to drying experiments to confirm the gradient structure formed. The ability of the hydrogels to transport the active species was confirmed by visually evaluating the permeation of the anionic dye (bromothymol blue) during the gelation process. From the results obtained during the experimental part of the bachelor thesis it can be concluded that the viscoelastic properties of hydrogels can be modified by changing selected parameters during the preparation itself. It was also confirmed the assumption that with better mechanical properties of hydrogels there is a deterioration of transport properties. By controlled diffusion method, it was possible to prepare a hydrogel with a gradual gradient of crosslinking density, thus modifying the viscoelastic and transport properties.
|
|
|
Characterization of minor fruit varieties in terms of use in the food industry
Jurečková, Zuzana ; Vítová, Eva (referee) ; Golian, Jozef (referee) ; Diviš, Pavel (advisor)
The thesis deals with one group of small fruits, the genus Ribes, ie currants, and gooseberries. It assesses their physical and chemical parameters with respect to the possibility of use in these properties for the design of a new type of product – beverages. Titration, spectrometric and other methods were used for the evaluation of these properties. A total of fifteen of these methods were available (total juice yield, juice pH, total dry matter, soluble fruit dry matter, titratable acidity, formolic number, reducing carbohydrate content, D-glucose, D-fructose and sucrose content, total polyphenolic substance content, anthocyanins, vitamin C and total antioxidant capacity) and a total of nine analytes (copper, iron, magnesium, phosphorus, zinc, manganese, potassium, calcium and sodium) were selected for the determination of mineral elements. For two years (harvest 2014 and 2015), these parameters were monitored for color variants of currants (white, red and black) and gooseberries (green-fruited, yellow-fruited and red-fruited). A total of six white varieties were tested in the group of currants - Olin, Jantar, Primus, Blanka, Viktoria and Orion, eleven varieties of red currants - Junnifer, Jesan, Detvan, Rovada, Rubigo, J.V.Tets, Tatran, Losan, Kozolupský raný, Stanca, NŠLS 11/6 and eleven varieties of black currant varieties - Ometa, Démon, Triton, Ben Hope, Ruben, Ben Gairm, Ben Lomond, Moravia, Ben Conan, Fokus and Ceres. A total of five varieties of green-fruited gooseberries were tested - Zebín, Mucurines, Rixanta, Rodnik and Prima. Yellow-fruited gooseberries were available in four varieties - Lemon Giant, Invicta, Golden Fig and Darek. The red-fruited gooseberries included varieties - Rolonda, Alan, Karat, Karmen, Krasnoslawjanskij, Himnomacki Rot, Remarka, Tamara and Black Neguš. Using Tukey's test, an analysis was performed and by scoring individual varieties based on the results of individual analyzes, a list of recommended varieties was compiled for further work on the development of a new beverage. Unfortunately, in 2015 there were very few fruits of green-fruited and yellow-fruited gooseberries, so it was decided that the volume of fruit will fall on the testing of bioactive substances. Therefore, at the end of the work, it is not possible to objectively evaluate these varieties of gooseberries in the whole range of analyzes. Therefore, the point evaluation of varieties was based on the averages of individual varieties. The red-fruited varieties were available in full, and therefore a full evaluation could take place. The most significant differences between red gooseberry varieties were in the content of bioactive substances (the content of polyphenolic substances, anthocyanin dyes, and vitamin C) and antioxidant capacity. These results were provided to the food subject, which continued to work with these values. Based on this project, utility model No. PUV 2016-33171 and the resulting combined drink based on wine and fruit juice were developed.
|
|
|
Weight control of soft cheese formed on a manual production line
Páral, Marek ; Zemanová, Jana (referee) ; Tomečková, Šárka (advisor)
The thesis deals with the control of the weight of soft cheeses during molding on a manual line. The theoretical part describes the classification of cheeses into groups, the basic characteristics of soft cheeses and their representatives. Furthemore, the whole technology of soft cheese production is processed and the effects on curd formation and factors influencing the weight of cheeses during molding are explained. The theoretical part ends with the basics of statistics for data processing. Basic measuring techniques (dry matter measurement, pH measurement, measurement of temperature and weight) were selected to determine the technological parameters (pH of whey, pH, dry matter and temperature of cheese grain, weight of cheese etc.) to describe the quality of grain in the experimental part of the thesis. The Design of Experiments method was used to find the optimal setting of the molding machine. Three partial experiments were designed and done. Results were verified in real production. The pH of whey was chosen to describe the grain quality. Two factors have been discovered that have a significant effect on the weigh of cheeses during molding, namely the position of the operator during molding and the amount of whey flowing into the forms with the cheese grain. The proposed molding modifications were successfully tested in production and no statistical difference was found between the weight of cheeses formed with the new setting of molding machine.
|
|
|
Study of selected technological properties of licorice mass
Gajdušek, Martin ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with the study of selected technological properties of liquorice matter. By microscopic observation it was found that at a content of more than 10% of the boiled starch grains or more than 30% of the non-swollen grains, the mass does not achieve the desired properties for further processing. Technological loss during drying depends mainly on time, but also on location in the oven, both in height and space. The highest technological loss was achieved mainly in the highest positions in the oven. By liquid chromatography was determined 11.8% glucose, 9.2% fructose, 23.3% sucrose in liquorice mass prior to cooking; 11.9% glucose, 9.4% fructose, 22.6% sucrose in cooked matter; 12.7% glucose, 10.8% fructose and 20.1% sucrose in dried liquorice products.
|
|
| |
|
|
Bioactive substances contained in elderberry pomace
Šimšová, Veronika ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with the determination of selected chemical characteristics in the elderberry juice, compote and in the extracts of elderberry marc. The theoretical part describes the botanical characteristics of elderberry (Sambucus nigra L.) including its occurrence, the possibility of utilization of individual parts of the plant in the food industry and in the healing therapies and chemical composition of the berries. The biggest attention is given to the bioactive compounds contained in these fruits. The second chapter deals with the dry matter and the methods of its determination. The last chapter of the theoretical part describes vitamin C, its importance for the human organism and manual methods for determination of vitamin C. Among the selected chemical characteristics, set out in the experimental part, was the determination of reducing sugars by gravimetric method and Berthrand method, titratable acids, total anthocyanins by pH-differential method, total phenolic compounds by the Folin-Ciocalteu method and determination of the dry matter by drying and refractometric method. Analyzes have proven that extracts made of elderberry marc under suitable conditions have, in most cases, chemical characteristics comparable to the elderberry juice and compote. However, extracts are much better source of anthocyanic and phenolic compounds than juice and compote.
|
|
|
Extraction of bioactive substances from black currant pomace
Sedláčková, Lucie ; Štursa, Václav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with extraction of bioactive substances from black currant pomace (Ribes nigrum). The theoretical part contains the botanical characteristics of the plant species Ribes nigrum. It is also devoted to the biologically active substances contained in black currant and possibilities of using black currant in the food industry. The fourth chapter deals with description of phenolic compounds, their distribution and methods of determination of phenolic substances. The fifth chapter describes selected extraction procedures. In the experimental part, there were extracted dry black currant pomace in order to optimize the extraction process and obtain the highest yields of dyes. In addition, were determined the selected chemical and physical characteristics of blackcurrant juice and extracts from blackcurrant pomace. A better solvent was a mixture of water and ethanol in a volume ratio of 1:1. After 14 hours maceration of dry pomace, were obtained 769,9 mg anthocyanins per 100 g of dry material.
|
|
|
Effect of different width of rows on biomass yield and dry matter content at growing sorghum
KUBEŠ, Pavel
The aim of this thesis was to determine the effect of row spacing on sorghum yields and dry matter. The trial was established on 29 May 2015 on land belonging to the Agricultural Cooperative Milevsko, which is situated in the corn-growing area. The trial compared four varieties of sorghum, namely Aristos, Goliath, KWS Freya and KWS Sole. The varieties were sown in different row spacings, namely 75 cm, 60 cm, 45 cm a 30 cm. The samples taken on three dates were analysed for dry matter content. Each variety showed a gradual increase in the dry matter content. During the harvest on 5 October 2015 the varieties KWS Freya and KWS Sole reached an optimal value of the dry matter when planted in all spacings. All varieties produced the highest average yield of green matter when planted in rows spaced 60 cm apart. The variety Aristos produced the highest average yield of green matter. The KWS Sole variety reached the lowest average yield of green matter when planted in rows 76 cm apart. All varieties with 60 cm row spacings, except for KWS Sole, produced the highest average yield of dry matter. The highest average yield of dry matter was reached by Aristos and the lowest by KWS Sole. The results of the one-year trial did not prove a direct connection of the effect of row spacing on dry matter. The effect of row spacing on green and dry matter yield was proved. The optimum row spacing seems to be 60 cm.
|
|
|
The posibility of applying corn hybrids with FAO number 300 in less favored areas
SLANEC, Roman
The aim of this thesis was to evaluate and compare production of biomass and dry matter of silage corn hybrids with different time of earliness - Ronaldinio (Z 240/S 250), Agro Vitallo (Z 270/S 280) and Balasco (Z 370/S 380). This experiment was realized on a field near České Budějovice ( 400 m.a.s.l.) and the resuls were compared to results of a pilot plant experiment realised by KWS OSIVA s.r.o. in ZOD Podhradí Choustník ( 562 m.a.s.l.). All startings of phonological phases were studied according to BBCH-scale in the course of vegetation period. Samples were taken before the harvest to test for contents of dry matter in biomass. They were used to determine the optimal harvest period. These parametres were observed during the harvest : plant height, biomass yield, dry matter of biomass, corncobs yield, share of corncobs, dry matter of corncobs, dry matter yield. The resuls showed succesful use of corn hybrids with higher FAO number (Balasco) in areas of less favourable conditions. Corn is one of the plants very dependent on the course of the year.
|
guest ::
