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Obsah zinku, mědi a jódu v mléce krav
JAKEŠOVÁ, Jitka
Milk and dairy products are one of the most important sources of essential trace elements in human nutrition. My thesis provides informations about the content of zinc, copper and iodine in milk during the lactation and also includes the impact of other factors on the content of elements. The experiment includes dairy cattle breedings from Hořepník and Chyšná which are located in the region Vysočina. Another breeding is from Haklovy Dvory. It is located in southern Bohemia. Milk samples were taken in the relation to performance monitoring. During the period 25 to 132 days of lactation were taken 90 samples of milk from the Hořepník breeding. From breeding Chyšná were taken 78 samples of milk in the period of 11 - 89 days of lactation and from breeding Haklovy Dvory 81 samples of milk during the period 23 to 244 days of lactation. Copper and zinc content in milk was determined by atomic absorption spektrometry. The iodine content in the milk was set by spectrometry after incineration alkaline by Sandell-Kolthoff. The average zinc content in the milk was 3.59 ? 1.15 mg-l-1. The average copper content in milk was 0.14 ? 0.12 mg-l-1and the average content of iodine in the milk was 0.18 ? 0 06 mg-l-1. The greatest variability in milk was proved to copper (V = 82,65%), the lowest zinc (V = 32,05%). The greatest effect of the duration of lactation was observed in breeding Hořepník (Zn: rxy = -0,430, Cu: rxy = -0,425, I: rxy = 0,326). The influence of the duration of lactation was insignifant in the breeding Haklovy Dvory and Chyšná. Cow's milk, according to our results, supply the iodine accounts from 19,2% for men and 52,4% for women. The milk supply the zinc accounts from 5,2 % for men and 7,2 % for women, and copper from 2,5% for both sex.
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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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Nutrition of infants and toddlers with allergies to cow's milk protein
VAVEROVÁ, Petra
The main objective of the thesis titled Nutrition of Infants and Toddlers with Cow's Milk Allergy is to outline the course of the disease and to present solutions to it. Another objective is to determine the frequency of milk allergy in the paediatrician's office. The thesis also aims to present a list of medical products for this type of disease. The theoretical part of the thesis deals with the classification of milk allergy in food allergies. Further, it discusses breast milk as the most important food for infants and the difference between breast milk and cow's milk. Finally, it discusses the very disease of cow's milk allergy, its prevalence, where and how it manifests most, methods of its diagnosing, and treatments available. In the end of the theoretical part, we deal with a list of artificial infant food suitable for children with cow's milk allergy. The research part of the thesis was developed by using qualitative research conducted through interviews with a dual focus with paediatricians. The first type of interviews with various paediatricians and a specialist physician were devoted to their knowledge, opinions, and information interesting for cow's milk allergy. The second type of interviews was aimed at patients with cow's milk allergy. These aimed to determine the course of the disease and diagnostic tests to identify the presence of the disease. Furthermore, they addressed the question of nutrition and current status of such patients. The theoretical part also includes an overview and evaluation of products of artificial infant food suitable for children with cow's milk allergy and in Nutriservis profesional I created a weekly diet for a child with an allergy to cow's milk protein.
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Parametry dojitelnosti a jejich vztah k množství, složení a technologickým vlastnostem kravského mléka
Mareš, Jiří
The aim of this thesis entitled Milking capacity parameters and their relation to the quantity, composition and technological properties of cow's milk is to present the issues related to this topic. This includes not only the literature search, but also its own research, that the sampling and analysis of milk and their subsequent confrontation with other studies that have been made. The theoretical part summarizes secretion and ejection of milk and its components, as well as the factors which influence both in terms of quantity and technological use. In the practical part of this thesis are then sampled milk cows monitored group and these samples subsequently processed detailed analysis. The result of analysis showed that there are many statistically conclusive relationship between the parameters of milking capacity and the amount, composition and technological properties of cow's milk. Conclusive relationship between the length of the total milk yield and milking, cows with milk yield greater than 10.6 kg of milk should milking time of 1.13 minutes longer than it was in dairy cows with lower production. The length of milking had a negative correlation with the absolute average minute gain (AAMG) and total milk yield. Dairy cows have been milking within 5 minutes had an average of 1.21 kg / min greater AAMG. These cows also had an average of 0.20 kg less milk than cows that were milked more than 5 minutes. Cows whose milk production per milk yield was more than 10.6 kg of milk have a lower fat content of 1.07%, compared to cows with lower production. Regarding the technological properties, proved that it was not a statistically significant relationship between the parameters and RCT milking capacity, consequently also the quality and curd. We also investigated the physicochemical properties of the milk which has been shown only a single relationship between these properties and parameters of the milking capacity, were active acidity whose value in dairy cows with higher milk yield was about 0.13 pH higher than that of cows with a lower milk yield was very pronounced influence individuality cows, which was reflected in the content of protein, lactose, non-fat dry matter further at RCT and all monitored physico-chemical properties.
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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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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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Využití NIR spektroskopie při kontrole falšování kozího mléka
Ptáčková, Eva
The aim of the thesis was to find out whether NIR spectroscopy is a suitable method for adulteration control of cow and goat milk. Also to which concentration level the method is still effective was sought. Theoretical part summarizes information about the requirements for goat milk, its composition and processing possibilities. It also contains information about food adulteration and the relevant legislation. Infrared spectroscopy is theoretically described, particularly NIR spectroscopy. The experimental part describes the procedure of qualitative analysis using NIR spectroscopy, the method of evaluation and its results. Different samples of goat milk adulterated with various proportions of cow milk were compared. Results were evaluated using discriminant analysis. NIR spectroscopy has been demonstrated as a method suitable for detecting goat milk adulteration.
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Iodine content in milk and milk whey during lactation
JAKEŠOVÁ, Jitka
Milk is an important natural resource of iodine in human nutrition. The content of iodine in milk is an objective indicator of iodine saturation of cows. My work shows data about iodine content in milk and whey during lactation and other factors which affect the iodine contents. The experiment includes 12 milkers at the beginning of their lactation. This milkers are from breeding Haklovy Dvory, which is situated near České Budějovice. Samples of milk were collected with monitoring performance regularly once a month since August to November 2014. The iodine content was determined spectrometrically after alkaline burning of the sample. The average content of iodine in milk in August 2014 was 169.63 ? 70.39 g.l-1, in September 202.25 ? 65.08 g.l-1, at the beginning of November (substitute sampling for October) 183.91 ? 65, 31 g.l-1 and at the end of November 2014 216.56 ? 68.67 g.l-1. The average iodine content in whey in August could not be realized. The average iodine content in whey in September was 140.5 ? 55,3 g.l-1, at the beginning of November 131.5 ? 45,9 g.l-1 and at the end of November 2014 168.2 ? 77, 8 g.l-1. The iodine content in the milk whey corresponds with the range for the recommended daily ration of iodine.
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Využití NIR spektroskopie při kontrole falšování kozích sýrů
Přikrylová, Iveta
Diploma thesis deals with use of near-infrared spectroscopy to detect falsification of goat's cheese. The basic knowledge of goat's and cow's milk and requirements for milk during cheese production are summarized in the theoretical part. There is also described the cheese production and the following part is devoted to food falsification with describing falsification of milk products and the facilities of adulteration detection by optical methods. The remaining part deals with NIR spectroscopy as a suitable method for the verification of food authenticity. The practical part is focused on the use of NIR spectroscopy to detect the difference between cheese samples with different concentrations of cow's milk in goat's cheese and subsequent use of discriminant analysis for evaluation. The results showed that the method is suitable for detection of falsification of goat's cheese and that is why could be useful for rapid analysis in practice.
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COWS MILK AS A NATURAL SOURCE OF IODINE IN HUMAN NUTRITION
VÍTKOVÁ, Lucie
This thesis deals with the importance of milk as a natural source of iodine in human nutrition. The thesis provides a data of the consumption of milk and milk products and their contribution to the protection needs iodine for students and employees of the University of South Bohemia in Ceske Budejovice. The experiment includes a total of 60 people (20 men and 40 women). Empirical data wasobtained within the grant project named GAJU 011/2013/Z and NAZV QH 81105. Data of consumption of milk and milk products were obtained through questionnaires. For men, average weekly consumption of milk was 826.5? 835.1 ml (118.1 ml per day) and for women 912.4? 783.9 ml (130.3 ml per day). Average consumption of yogurt for men was 361.0? 401.4 g per week (51.6 g per day), for woman 428.4? 338.8 g per week (61.2 g per day) and average consuption of cheese was for men 263.0? 240.5 g per week (37.6 g per day) and for woman was 260.2? 226.5 per week (37.2 g per day). Through the milk and milk products tested, men average 81.6 g of iodine per day, woman adopted 93.4 g. According to the results, the amout of consumed milk and milk products was lower than the nationwide average, but still covered more than half of daily iodine needs. The thesis presents the data of the iodine concentration in urine for students and employees of the University of South Bohemia in Ceske Budejovice (n=62) as an indicator of iodine supply to the organism. The average iodine content in urine of all subjects (men and women) was 230.4? 171.3 gl-1, for men (n=21) reached 244.6? 195.2 gl-1, for women was 223.2? 159.8 gl-1. Results of the average iodine content in urine reflected the physiological range, i.e. for the students and employees of the University of South Bohemia was supply of iodine in organism sufficient. The thesis also provides information about the amount of iodine in asamples of cow´s milk on a selected farm (n=50) of the Jihocesky region, the Plzensky region and Vysocina during the years 2011 - 2013. Samples of cow´s milk were obtained in collaboration with the Central Laboratory of dairy Madeta a.s in Ceske Budejovice and Veterinary Centre s.r.o Susice. In 2011, the average concentration of iodine was 321,0? 337.8 gl-1, in 2012 was concentration of iodine 298.8? 290.8 gl-1 and in 2013 was 234.7? 116.1 gl-1 also otherwise: in all years was it was determined that there was an abundance of iodine. The highest values (315.6? 305.1 gl-1) of iodine was in the Jihocesky region. In Vysocina a lower average level of the iodine was detected (9.5 %), as well as in the Plzensky region where the amount of iodine in milk was lower by 53.7 %, compared to the South Bohemia region and 48.8 % compared to the Vysocina region.
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