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Milk composition changes after fortification milch cow feed with selected additive
Tůmová, Michaela ; Hrstka, Miroslav (referee) ; Křížová,, Ludmila (advisor)
This thesis is dealing with effect of supplement limiting aminoacid histidin, that was applied as duodenal infusion, on yield and composition of high production dairy cows milk. The theoretical part describes overview about milk composition and metabolism of dairy cows. There are described nutrition requirements of dairy cows for esential aminoacids. In this part are also presented principles of analytical methods used for analysis of milk. For determination of basic components of milk were used infrared spectroscopy and enzymatic-conductometry. Aminoacid profile of casein was determined by ion exchange liquid chromatography. In the experimental part is described method of experiment. There is described technique of acid and oxidative hydrolysis of lyofilized casein and technique of determination aminoacids in this hydrolyzated casein. Results of analysis were interpreted and discussed with literature. This diploma thesis was made as a cooperation between the Institute of Food Science and Biotechnology, the Faculty of Chemistry, University of Technology, Brno and the Research Institute for Cattle Breeding, Department of Animal Physiology and Nutrition, Pohorelice.
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The study of various methods of preparation of the milk sample for milk analysis by ICP-OES technique
Kaňová, Veronika ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
The theoretical part of the thesis deals with the chemical composition of cow’s milk, with the description of chosen methods of sample pretreatment and with the description of the used technique ICP-OES. The practical part is aimed at individual preparations of samples and at analysis of chosen chemical elements (Ca, Na, K and Mg). Milk is a really complicated polydisperse system, that’s the reason why the preparation of samples with milk is very important step before the measurement itself. In addition to accuracy choosing the sample adjustment method, other factors such as time, work intensity, or cost need to be considered when. In the thesis a comparison of four selected methods of sample preparation was made: direct analyse of milk, dilution with addition of Triton X-100, wet microwave ashing and destruction of matrix with TMAH (tetramethylammonium hydroxide). Selected elements were analysed with the help of ICP-OES. This diploma thesis builds on the bachelor thesis, which deals with the same problem. Final concentrations were compared with certified values of skimmed powdered milk. Data showed that the most accurate are methods of preparation of wet microwave ashing and destruction of matrix with TMAH. By using these methods, the effect of the dairy matrix that caused problems in the analysis, was largely eliminated. The diluted samples with and without Triton X-100 showed a bigger anomaly of measuring than the mineralization of wet ashing which came to the loss of analyte because of fat elements contained in milk.
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Analysis of milk by ICP-OES technique
Kaňová, Veronika ; Hrstka, Miroslav (referee) ; Diviš, Pavel (advisor)
The theoretical part of the thesis deals with the chemical composition of cow’s milk, with the description of chosen methods of sample pretreatment and with the description of the used technique ICP-OES. The practical part is aimed at individual preparations of samples and at analysis of chosen chemical elements (Ca, Na, K, Mg a P). Milk is a really complicated polydisperse system. The preparation of samples with milk is very important step before the measurement itself. In the thesis a comparison of four selected methods of sample preparation was made: bare dilution, dilution with addition of Triton X 100, wet ashing and sonication. Selected elements were analysed with the help of ICP-OES. Final concentrations were compared with CRM of dried milk. Data showed that the most accurate are methods of preparation of diluted sample and wet ashing. Four different types of milk were analysed with the help of those two selected methods. The diluted samples showed a bigger anomaly of measuring than the mineralization of wet ashing which came to the loss of analyte because of fat elements contained in milk.
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Spotřebitelské chování na trhu s mlékem a jeho rostlinnými alternativami
Zemanová, Eliška
The thesis is focused on the characterization of segment of final consumers of cow's milk and plant-based milk alternatives in the Czech Republic. The aim of the thesis is to analyze the consumer behaviour of people interested in the consumption of the mentioned products. The literature review was followed by a description of the market for milk and plant-based milk alternatives. The research was carried out in the form of a questionnaire survey, in which 383 respondents was originally participated, but 6 respondents were subsequently removed from the research due to incorrect completion of the questionnaire. The established hypotheses were evaluated by the Pearson Chi-Square Test. The research found out that more respondents consume cow's milk than plant-based milk alternatives, that consumers are willing to pay more for higher quality products, and in the area of plant-based milk alternatives, according to a minority of respondents, there is a demand for a larger assortment. In conclusion, recommendations for business entities operating in the market were proposed.
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Změny ve složení a technologických vlastnostech kravského mléka v průběhu dojení
Vávrová, Růžena
The aim of this thesis was to analyze changes in the composition and technological properties of cow's milk during the milking. Part of the work was practical research on the farm and subsequent analyzes of milk samples obtained from four cows. Samples were taken during milking using a special cane that allowed the milk to be divided into four fractions. The 1st fraction was obtained at the beginning of milking, 2nd and 3rd during and 4th fraction at the end of milking. Average values of samples of milk were as follows: 1.72 kg quantity of milk, fat content 4.1 %, protein content 3.09 %, lactose 4.62 %, non-fat dry matter 8.41 %, ash 0.69 %, density 28.51 kg/l, 1.11 % water, the freezing point of -0.538 °C, rennet coagulation time 136.59 sec and 1.47 the quality of the curd. From the results of this research, I can say that the influence of the individual milk fraction has greatly influenced its quantity, fat content, density, water percentage and milk freezing point. For other monitored components, the effect was inconclusive. The individuality of the cow has a significant influence on the quantity of milk. The fact that the milk was obtained in summer or winter significantly affected fat, protein, lactose, non-fat dry matter, ash, density, water percentage and milk freezing point. The remaining monitored parameters have been implicitly affected.
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Výskyt a charakteristika meticilin rezistentních stafylokoků v chovu mléčného skotu
Pajtina, Luboš
The focus of this thesis is the confirmation of the presence of the methicillin-resistant Staphylococcus aureus on a selected dairy bovine farm and the following typing of its isolates while using common genotyping and phenotyping methods. After the isolation of this bacteria from the samples, they were tested for the presence of mecA gene and the genes responsible for the production of enterotoxins. It was tested whether the isolates belong to the 398 sequence type and their type of spa gene sequence was determined. Then the resistance against antimicrobial agents was tested. Results of the typing were compared to those of other related articles. Finally, this thesis observes the efficiency of the sanitizing agent used at this farm and suggests further methods to reduce the occurrence of MRSA in this herd.
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Calcium intake in children with cow's milk protein allergy
BÍLKOVÁ, Kateřina
The bachelor thesis deals with the calcium intake in children with cow's milk protein allergy from their diet. As the first aim I chose to inform parents about possibility of deficiency of the calcium intake in children with cow's milk protein allergy. The second aim is to find out the calcium content in the diet of children with this allergy. In the theoretical part of my bachelor thesis I briefly describe food allergy in general then I focuse on cow's milk protein allergy, types of reactions, symptoms, diagnostics and therapy. As the topic of this bachelor thesis is calcium intake in children with cow's milk protein allergy, the next part is devoted to calcium, its importance in human body, absorption, usability and also resources. At the end of theoretical part of this thesis I mention the specifics of nutrition in children with this allergy, such as different labeling of ingredients containing milk protein on food packaging or in composition of dishes, and also possibility of replacing milk and milk products in terms of consistency and taste. In the practical part of this bachelor thesis I cooperate with mothers of children with cow's milk protein allergy who give me one week menu of their children, from which I calculated the calcium intake for each day and also the average weekly calcium intake per day. I also informed these mothers about the possibility of calcium deficiency in their children's diet. Calcium intake approaching the recommended daily intake for a group of children aged 1-3 years occured only in one case. In four cases was the intake of calcium from children's diet lower than 50 % of the recommended daily intake for these children.
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Clotting of cow and goat milk
PECOVÁ, Lenka
The thesis deals with two technological properties determining the quality of milk, clotting and fermentation ability by titrable acidity, which are influenced by a large number of factors. The aim of the work was to assess the influence of milk composition, breed, order and stages of lactation on clotting and souring ability of cow and goat milk based on obtained analysis. Detailed analysis focused primarily on cow milk.
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