National Repository of Grey Literature 117 records found  beginprevious88 - 97nextend  jump to record: Search took 0.03 seconds. 
Determination of basic nutritional parameters in edible insects
Korček, Jakub ; Štursa, Václav (referee) ; Diviš, Pavel (advisor)
In this bachelor thesis is dicussed nutritional value of chosen insect species. Analysed samples consisted of worms, crickets and locusts. Analysed parameters were: total nitrogen, crude protein, total lipids and content of chosen elements. Total lipids were, after homogenization, determined by Soxhlet method, using diethyl ether as a solvent. Prior to protein and element determination, samples did undergo Kjehldal digestion process, using sulfuric acid. Weiniger catalyst was only added to samples digested for protein measurement. Element content was determined by optical emission spectrometry with inductively coupled plasma (ICP-OES). Crude protein was determined by Kjeldahl method. The highest protein content was determined in crickets. (75 ± 5) %. Locusts contained the highest lipid content (33 ± 2) %. We also found out, that samples were rich in calcium, potassium, manganese and zinc, which are all important elements for the proper functioning of our body. The results of this thesis prove, that insects can present nutritionally important food.
Monitoring of selected metals in comercial bio wines
Bortlová, Alžběta ; Reichstädter, Marek (referee) ; Pořízka, Jaromír (advisor)
This bachelor thesis is focused on monitoring of selected metals in commercial organic wines. The aim of this thesis was to compare element content of organically produced wines with wines originating from other agrotechnical production system. Optical emission spectrometry with inductively coupled plasma (ICP-OES) was used for element analysis of wine. Statistical method analysis of variance has been used to assess whether the concentrations of the elements showed statistical differences between wines originating from organic production and wines originating from other production systems. Statistical differences were found in 3 of 20 analysed elements. Correlations between the element analysis and type of production system of grapevine were observed in content of the zinc, nickel and manganese.
Influence of the chicken breeding method on the selected chemical constituents of chicken eggs
Michalec, Adam ; Vespalcová, Milena (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis is focused on the analysis of egg yolks and egg whites from chickens raised with different breeding methods in the Czech Republic using three analytical methods. The Kjeldahl method was used to determine the proteins, the Soxhlet method was used to determine the lipids and ICP-OES was used for elemental analysis. The theoretical part describes the history of chicken breeding, marking and distribution of eggs and composition of eggs based on various aspects. The main point was the separation of egg yolk and egg white and the subsequent description on the chemical and physiological level. Principle of used methods is also described. The experimental part deals with the preparation of samples, calibration samples and process analysis. All the results of analysed substances are summarized, statistically evaluated and compared with the other literature. For this analysis were used eleven different types of eggs from the Czech Republic from six different categories.
Elemental analysis of cheese with white mold on the surface
Pavlechová, Alžbeta ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
This Master's thesis deals with elementary analysis of cheeses with white mold on the surface. Theoretical part describes general characteristics of cheese, classification of cheeses, their nutritional aspects and characteristics of cheeses with white mold on the surface. Large part is focused on description of mineral substances selected for analysis. At the end of the theoretical part, the Kjeldahl method and emission spectrometry with inductively coupled plasma (ICP-OES) were described. Experimental part deals with preparation of samples, approach of analysis and processing of measured results. Eleven samples of cheeses were used for analysis. These samples were from Czech Republic, France and Slovak Republic. Kjeldahl method was used to determine protein contents and ICP-OES was used for elemental analysis. The results were compared to each other and also with results from other studies. Subsequently, they were statistically processed and evaluated in the final part.
Analysis of czech garlic varieties
Fähnrichová, Nikola ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
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.
Determination of iodine in food
Malčíková, Hana ; Reichstädter, Marek (referee) ; Diviš, Pavel (advisor)
The bachelor thesis deals with the optimization of ICP-OES method to determination of iodine in mineral waters. At first, the Theoretic part characterize the iodine in general, next it concerns with it as the essential/biogenic element, which is necessary for the proper functioning of the human organism, with its occurrence in food and with its industrial utilization. In next chapters the thesis is describing analytical methods of iodine determination specifically ion chromatography and inductively coupled plasma optical emission spectrometry. The principle and instrumentation description of both methods are found. The Experimental part is focused on optimization of ICP-OES methods, device setup for IC, on preparation of samples of mineral waters and the samples analysis using both methods. The results of the Experimental part show a content of iodine in mineral waters accessible in the Czech Republic and the Slovak Republic.
Characterization of humic substances isolated from natural waste treated by vermicomposting process
Marková, Kamila ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis deals with the study of humic substances isolated from vermicompost natural waste through spectrometric methods. The aim of this thesis is to study physicochemical properties of the humic substances through modern instrumental techniques such as molecular absorption spectroscopy in the ultraviolet and visible regions of electromagnetic radiation (UV/Vis), infrared spectroscopy with Fourier transformationn (FTIR), elemental analysis (EA), thermogravimetric analysis (TGA) and inductively coupled plasma emission (ICP OES). A research focused on basic information about the humic substances was developed in the theoretical part. A description about their distribution or structure was made and also their utilization in medicine, industry or ecology. Then, methods, which are used for study of the humic substances, were described as well. An essential part of the thesis was isolation of humic and fulvic acid from the vermicompost natural waste. Absorption coefficients were calculated from the measured UV/VIS spectrum which served to following characterization of HK and FK. FTIR spectrum was used to determination of functional groups of studied HL. An area of biogenic elements was specified using the elementary analysis. Total amount of studied trace elements was determined with with the help of ICP-OES.
Investigation of the effect of creatine in combination with magnesium and vitamin C on the performance of the individual person
Vlasák, Jan ; Němcová, Andrea (referee) ; Diviš, Pavel (advisor)
Creatine is nitrogen-containing organic acid which naturally occurs in the human body. The aim of this work was to determine the optimal dose of creatine in combination with vitamin C and magnesium for male respondents aged 18-26 years. They were divided into two groups differing in the creatine dosage. Group 1 took smaller dose of creatine (3 g per day) and group 2 higher dose of creatine (10 g per day). Both groups took both magnesium and vitamin C at constant doses throughout the study. The effects of significantly different dose of creatine in the individual groups were compared with each other in terms of the performance of individuals in the powerlifting, the anthropological changes and the overal metabolism of the intakes. In all disciplines of powerlifting, group 1 recorded higher average weight gains, which were not found to be statistically significant at a significance level of alpha 0,05. Anthropological changes were measured using the InBody 160 and a diagnostic measuring tape. In both cases, group 1 recorded better results than group 2, but these results were not statistically significant at a significance level of alpha 0,05. The total metabolism of the accepted dietary supplements was investigated through analytical methods. The urine of each respondent was regularly collected and subsequently analyzed during the research. Determination of creatinine, a creatine waste product, was performed by UV-VIS spectrophotometry using the Jaffe reaction. Vitamin C was analyzed by RP-HPLC. Magnesium was determined by the ICP-OES method. After creatine suplemantion of 3 per day, group 1 showed a slight increase in creatinine in the urine, but still in the physiological range. At the significance level alpha 0,05 there was no statistically significant difference. Group 2 showed an increase above the physiological limit which was already a statistically significant difference. Overall, creatine supplementation of 3 g per day has been found as a sufficient intake of creatine needed to build up muscle mass, increase energy metabolism and overall physical performance. The metabolization itself works very well and within the physiological values.
Crystal chemistry of pyralspite garnets
Soumar, Jan ; Skála, Roman (advisor) ; Ulrych, Jaromír (referee)
Bohemian garnets have been known as a jewellery stone for many centuries. There is still a lot of interest in them, however, the reserves in traditional locations are getting smaller. That is why search for alternative source of similar garnets in gem quality started. Shavaryn Tsaram deposit in Mongolia is considered as one of the potential sources. Pyrope samples from eight Bohemian localities of two areas (České středohoří [The Central Bohemian Uplands] and Podkrkonoší [The Giant Mountains]) and from Shavaryn Tsaram deposit in Mongolia were analysed using electron microprobe, LA-ICP-MS, ICP-OES, Mössbauer spectroscopy and x-ray powder diffraction. The data were compared with the conclusion that the Mongolian garnets from Shavaryn Tsaram deposit are so different from the Bohemian ones that it will not be possible to use them as a gem material of similar qualities. Bohemian garnet can be characterised as a red garnet with refraction index 1.747 (+/- 0.001) with dominant pyrope component of the average composition Py78Alm17Gr5 and Cr2O3 content above 1 wt.%. The data were also evaluated from two classification schemes point of view. The schemes by Schulze (2003) and Grütter (2004) are used in determining source materials and in diamond prospection. According to them source rocks of Bohemian garnets...
Determination of the nutritional properties of paprika of different geographic origin
Kovaříková, Tereza ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This master thesis deals with the analysis of nutritional properties of paprika condiment with different geographic origin. The theoretical part contains botanical description of red pepper (Capsicum annuum L.), its chemical composition, process of production of paprika and then they are described analytical methods suitable for determination of fundamental nutrional properties. Experimental part is focused on the preparation of samples and their analysis. In total, 11 samples were selected for the experiment, 5 of them had a protected designation of origin. These samples were from Slovakia, Hungary, Bulgary, Romania, Turkey and Spain. The Soxhlet extraction was used for the analysis of the fat content, Kjeldahl method was used to determine gross protein. High-performance liquid chromatography (HPLC) was chosen to determine carbohydrates and capsaicin. Induction-coupled plasma emission spectroscopy (ICP-OES) was used for elemental analysis. The results were compared with each other and with available databases and literature. For comparing and finding certain connections, the principal component analysis (PCA) was selected.

National Repository of Grey Literature : 117 records found   beginprevious88 - 97nextend  jump to record:
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