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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Možnosti fortifikace vybraných cereálních výrobků / Fortification of selected cereal products

Hurtová, Jana January 2012 (has links)
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.
22

Stanovení makroprvků, organických kyselin a dalších parametrů v kečupech / Determination of macroelements, organic acids and other parameters in ketchups

Popelová, Nikola January 2017 (has links)
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.
23

Znalosti vybrané skupiny pedagogů o výživě a vlivu stravy na lidský organismus / Knowledge of a selected group of teachers about nutrition and the effect of diet on the human body

Houšková, Michaela January 2022 (has links)
This diploma thesis, "The knowledge of a selected group of teachers about nutrition and the influence of food on the human organism" aims to find out about the level of knowledge that the teachers of the lower secondary stage of primary schools and the corresponding years of grammar schools possess in the field of nutrition and its influence on the human organism. Nutrition is a necessary part of life and the knowledge of proper nutrition is essential for the correct function of the human organism, prevention of various diseases, etc.; nutrition in children is evidently even more important than in adults. Furthermore, nutrition helps to improve academic importance, which is why teachers should have at least some level of knowledge in this field. In the theoretical part I try to sum up the very basics of the individual areas of nutrition, including a recommended fluid intake, micronutrients and macronutrients, or the influence of nutrition on the human psyche. The research for this thesis was done via a questionnaire survey, in which 260 teachers took part. The teachers came from randomly selected schools; their contact information was all publicly available and obtained from the websites of the individual schools. The questionnaire included 25 questions altogether and, among others, it also...
24

Stanovení vybraných chemických parametrů plodů šlechtěných odrůd bezu černého / Determination of selected chemical parameters of fruits of cultivated elderberry varieties

Hamalová, Veronika January 2014 (has links)
In this thesis was determinated selected chemical and nutritional parameters in the wild elderberry and 17 cultivated varieties of elderberry. The fruits was provided by the Research and Breeding Institute of Pomology Holovousy Ltd. The theoretical part deals describes elderberry, chemical composition of elderberry, especially biological active substances and its using not only food industry. Closer attention has been focused on effect of saccharides, anthocyanins and methods of their determination, specially determination by HPLC. The experimental part describes the various methods of determination of selected chemical and nutritional parameters. Total dry matter, content of total polyphenolic compounds, monomeric anthocyanin pigment and antioxidant activity was defined in all varieties of elderberry fruits. For some varieties was defined total soluble dry matter, content of organic acids and saccharides by various methods. In the end was compared the values from different methods varieties.
25

Charakterizace odrůd minoritního ovoce z hlediska využití v potravinářském průmyslu / Characterization of minor fruit varieties in terms of use in the food industry

Jurečková, Zuzana January 2021 (has links)
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.
26

Analýza vybraných odrůd českého česneku / Analysis of czech garlic varieties

Fähnrichová, Nikola January 2018 (has links)
This master thesis deals with analysis of Czech garlic varieties in comparison with two varieties from abroad. Alliin and carbohydrates were determined by high performance liquid chromatography with diode-array detector or evaporative light scattering detector. Crude proteins were calculated from total content of nitrogen that was determinated by Kjeldahl method. Elementary analysis was performed by inductively coupled plasma optical emission spectrometry. In theoretical part of this thesis is describes botanical characterization and cultivation of garlic, chemical composition of garlic, especially groups of substances which were analysed in this thesis. Principle of used methods is described too. The experimental part of this work deals with sample and calibration solution preparation and process of analysis. Obtained results from analysed substances are summarized in the tables, discussed and compared with results of analysis of other authors. Between Czech and Spanish/Chinese garlic are slight differences. Garlics contain 24,66 g/kg dry weight of alliin. Content of crude proteins in Czech garlic is comparable to Chinese garlic but the Spanish garlic has just half of amount crude proteins. Elementary analysis also includes significant differences. Czech varieties contain higher amount of phosphorus, iron and zinc. On the contrary, content of potassium in foreign garlic is higher than in Czech Republic and the analysed amount is 15 g/kg dry weight.
27

Potravní doplňky ve sportovní výživě a možnosti sledování jejich vlivu na výkonnost sportovce. / Dietary supplements in sport nutrition and possibilities of monitoring their effect on efficiency of sportsman.

Vlčková, Lenka January 2008 (has links)
This work deals with dietary supplements intake and its impact on the performance rise and muscle mass growth of bodybuilders. Twenty-five students (bodybuilders) were chosen for the purpose of this survey; they were divided into four groups according to the dosage of creatine and other dietary supplements (proteins and maltodextrine). Changes of the measured parameters (weight; bustline; weistline; limb girth; body lipid content; creatine and urea content in the urine) were compared during the survey. The tested dietary supplements impact on the muscle mass growth was evaluated on the basis of the acquired results.
28

Vývoj vybraných doplňků stravy - klimakterium / Evaluation of selected dietary supplements - climacterium

Tobolková, Blanka January 2009 (has links)
A dietary supplement is a product that contains nutrients (e.g. vitamins, minerals, herbs, amino acids or fatty acids) intended to supplement the diet. The aim of the diploma thesis was to suggest a prescription for preparation of three types of dietary supplements which are used to reduce of climacteric symptoms, their production and determination of energetic (nutrition) value on account of detected content of proteins, fats and saccharides in dietary supplements. A part of the diploma thesis was to suggest suitable wrapping and price of prepared dietary supplements. The three dietary supplements were used for analyses, namely capsules, herb syrup and herb drops. The content of proteins was determined by Kjeldahl´s method, total fats were determined by Soxhlet extraction and saccharides were determined by titration with potassium permanganate (Bertrand´s method). Dietary supplements in form of capsules were particular analysed on content of heavy metals (lead, cadmium and arsenal). In herbal drops was in addition determined alcohol content (ethanol). There was from the measured data found out, dietary supplement in form of capsules was chosen as the product with the lowest energetic (nutrition) value.
29

Doplňky stravy s adaptogenními účinky / Dietary supplements with adaptogenic effects

Izraelová, Alexandra January 2010 (has links)
The aim of this thesis was to design a recipe for the dietary supplements with adaptogenic effects, production, and subsequent analysis (proteins, lipids, carbohydrates), which led to the determination of the energetic value of preparation. Adaptogenic effects are the domain of plants and fungi, known as adaptogens. Adaptogens act non-specifically to the human body - improve the overall condition of the body, accelerate healing and regenerative processes, slow degenerative processes in the body and thus the aging process. As biogenic active stimulators, they affect not only in the physical but also in mental area. Dietary supplements have been designed in three different forms - capsules, syrup, drops. The analysis was also performed in tablets of Vietnamese origin supplied by supervizor, of which entry to our market is being considered. Protein content was determined by Kjeldahl method, lipids by Soxhlet extraction, saccharides by gravimetric method. Dietary supplements were analyzed for heavy metals (Pb, Cd, Hg), and in herbal drops ethanol content was determined.
30

Vliv listového dusíku a nestrukturních sacharidů na obsah a aktivitu enzymu Rubisco v podmínkách normální a zvýšené koncentrace oxidu uhličitého / Influence of total leaf nitrogen and non-structural carbohydrates on Rubisco content and its activity under ambient and elevated concentrations of carbon dioxide

Vičíková, Magda January 2011 (has links)
This diploma thesis examines influence of content of leaf nitrogen and non-structural carbohydrates on Rubisco activity and its content under impact of ambient (A = 385 µmolCO2 mol-1) and elevated (E = 700 µmolCO2 mol-1) concentrations of carbon dioxide in needles of Norway spruce (Picea abies L.). The Rubisco activity was determined spectrophotometrically, the Rubisco content by using SDS-PAGE, the content of non-structural carbohydrates by using the anthron method and total leaf nitrogen was determined by using the Kjeldahl method. The Rubisco activity in needles of Norway spruce did not show acclimation on elevated concentration of carbon dioxide, but the activity was elevated concentration of carbon dioxide stimulated during the growing season. The acclimation was proved by Rubisco content, its content was significantly lower in needles cultivated under elevated carbon dioxide. Content of total leaf nitrogen was statistically significantly lower in needles of Norway spruce cultivated under elevated carbon dioxide then in needles cultivated under ambient concentration of carbon dioxide. On the contrary, the content of non-structural carbohydrates was significantly higher in needles cultivated under elevated concentration of carbon dioxide then in variant A. Seasonal changes of Rubisco content depended on content of non-structural carbohydrates, the Rubisco content decreased with increasing content of non-structural carbohydrates. No dependence was detected between seasonal changes of the total leaf content and the Rubisco content.

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