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The assessment of basic chemical parameters of natural cheese
Školová, Dominika ; Babák, Libor (referee) ; Vítová, Eva (advisor)
The aim of this work was to determine basic chemical parameters of natural cheese, namely Camembert type (white mold cheese) and Emmentaler type (cheese with high-heat curd). Model samples of cheese were produced in a pilot plant using unpasteurized milk in"organic" quality. Based on the literature search following parameters suitable for simple and fast characterization of cheese composition were selected: dry matter (drying to constant weight), fat in dry matter (calculated), total nitrogen (resp. determination of protein content) by the Kjeldahl method and fats, resp. total lipids (extraction with solvent). The results were finally compared with samples of the corresponding cheese type purchased on the market.
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Determination of selected nutritional parameters in the fruit of the plant genus Ribes
Ledvina, Vojtěch ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis focuses on the small fruit representatives from the plant genus Ribes L. - currant, gooseberry and jostaberry. The beginning of theoretical part describes history of cultivation and basic botanical description of individual cultivars. The next part describes important substances contained in fruit as well as their importance in human diet and it also describes some basic products made of the Ribes L. genus representatives. The final section of the theoretical part contains basic principal of determination of individual nutritional parameters. In the experimental part several nutritional parameters were determined including dry matter, soluble solids, pH, titratable acids, formol number, reducing sugars and total phenolics. Individual species and cultivars were compared based on the results.
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Determination of basic chemical characteristics of blackberry pulp
Pilátová, Anna ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with determination of selected chemical characteristics of juice, pulp and extract prepared from blackberry of two species, from The Czech Republic and Ukraine. The theoretical part contains the botanical characteristics of blackberry, the content of active substances and possibilities of use of blackberries in the food industry. The following chapters focus on the description of phenolic substances and the determination of pH and titration acidity of fruit juices by manual methods. In the experimental part, two extraction solvents were first compared for extraction of anthocyanins from blackberry moldings. Furthermore, the selected chemical and physical properties of extracts, juice and pulp from blackberries were determined. The analysis was carried out for blackberries from the Czech Republic and Ukraine. A 1 : 1 mixture of distilled water and ethanol was a better extraction solvent for the content of anthocyanins. After 14 hours of maceration 150.4 mg of anthocyanins was obtained from 100,0 g of blackberry moldings Extract from blackberry moldings has been determined to have a much higher concentration of anthocyanins than juice and pulp. The extract of Ukrainian blackberries contained 197.4 mg CGEdm-3 and extract of Czech blackberries 150.4 mg CGEdm-3. Also phenolic substances had the highest concentration in extracts. Ukrainian blackberries contained 3501.9 mg GAEdm-3 and Czech blackberries contained 3256.1 mg GAEdm-3.
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Selected nutritional parameters of some lesser known fruit
Diblíková, Michaela ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
Diploma thesis is focused on the chemical analysis of the juices of black, red and white currant and jostaberry (Ribes a Ribes x culverwellii). The theoretical part is focused to the definition of fruit, fruit importance in human nutrition, description of Ribes and Ribes x culverwellii genuses, active substances in the currants and the jostaberry, description of selected chemical parameters and the determination of some of them. The procedures of determining for the following chemical parameters are described in the experimental section: determination of reducing sugars, determination of total and soluble solids, formol number, pH, titratable acidity, determination of total phenols and anthocyanins and determination of vitamin C in two samples jostaberry, six varieties of black currants, one variety of white currant and two varieties of red currants. Based on the evaluation of the obtained results, the comparison was made with different varieties and the thesis that "overall comparison of the different varieties in the content of phenolic compounds, vitamin C and anthocyanins appears to be the most promising variety of blackcurrant demon. It should however be noted that the highest content of phenolics and anthocyanins were determined in jostaberry„ has been suggested.
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Basic characterization of selected samples of animal feeds
Svoboda, Ilona ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
The aim of the diploma thesis was to choose poper parameters for a quick and simple characterization of animal feed, to verify working procedures and to apply these on chosen samples. Within the scope of this work, samples of animal dog feed produced in a private company „Adamkovy tlacenky“ were analyzed. The feed is in the form of brawn, stored in artificial casing; it consists of up to 80% of animal components and up to 20% of vegetable components, while the rest of the weight is the pork gelatine. The feed does not contain preservatives, colourings as well as any other chemically produced additives. For the analysis three formulas were chosen: "Hovězinka", "Kuřátko" and "Srdcovka", the composition of which is protected by the patent. The choice was made to include samples of different composition. The content of raw crude protein, fat, fibre, dry basis, and ash was determined. The obtained values were compared with the standards for feed normally utilized by the feed industry. The results will be used to improve the formulas and to develop new types of feed.
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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.
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Basic chemical characteristics of juices of selected white currant varieties
Zlámalová, Petra ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
The bachelor thesis deals with determination of basic chemical charcteristics of juices of selected white currant varieties. The theoretical part focuses on botanical description of the plant, history of cultivation, important chemical substances contained in the fruits and their effects on human body. There is also described use of white currant in the food industry and the basic principals of determination of the juice parameters, there. The experimental part focuses on determination of juice yield, soluble solids, pH, dry matter content, titrable acidity and formol number. Based on resultes, the individual cultivars were compared. The determination showes that cultivar Olin has the highest titrable acidity and the most of soluble solids at all. Cultivar Orion has the biggest juice yield, cultivar Primus has the biggest dry matter content and cultivar Jantar has the highest formol number and pH.
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Determination of macroelements, organic acids and other parameters in ketchups
Popelová, Nikola ; Divišová, Radka (referee) ; Diviš, Pavel (advisor)
The aim of this master’s thesis is perform basic analyses of samples ketchups. The theoretical part describes the basic characteristics of tomato, tomatoes processing and production of puree and ketchup. Then there are described analytical methods which were used for analysing the selected parameters in ketchups. The experimental part deals with the determination of pH, total solids, organic acids, saccharides, macroelements and lycopene in ketchups. Citrate and acetate were analysed by IC. The amount of acetate in ketchups was about 5 times greater than the amount of citrate. Glucose, fructose and sucrose were analysed by HPLC. Glucose and fructose were determined in all samples but sucrose not. The ICP-OES method was used to determine four elements. Magnesium was the least represented element and sodium was the most represented element in the analysis. The amount of sodium was recalculated on the amount of salt. Lycopene was analysed by UV-VIS spectrometry. Its amount in ketchups is influenced by the variety of used tomatoes and plenty of other factors.
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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.
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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.
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