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Analysis of selected elements in milk by ICP-OES
Sekaninová, Renáta ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This Master's thesis is dealing with elementary analysis of milk. Theoretical part describes general characteristics, terminology with basic legislature and classification of milk. Large part is focused on chemical composition, especially on description of mineral substances selected for analysis in experimental part of this thesis. Choices of elementary analysis and preparation of samples for ICP-OES method conducted by other authors are also mentioned. Specification of emission spectrometry with inductively coupled plasma is crucial, a technique used for purposes of this dissertation. Experimental part deals with preparation of samples, approach of analysis and processing of measured results. The aim of this part is to compare concentration of analyzed elements in different kinds of milk. Samples from 15 different kinds of milk were used for analysis, which were determined by ICP-OES method. Results were compared to each other in discussion as well as with results from other authors.
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Determination of microelements by ICP-OES after extraction by DGT technique
Habartová, Aneta ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This thesis is focused on determination of microelements (Cd, Co, Cu, Fe, Mn, Ni, Pb a Zn) in milk by optical emission spectrometry with inductively coupled plasma (ICP-OES) after extraction by Diffusion Gradients in Thin films technique (DGT) containing Chelex 100 resin gel and agarose diffusion gel. The optimalization of DGT in model metal solutions was verified by recommended basic tests. The performance of the DGT technique in the diluted milk matrix was verified. By DGT technique was determined only Zn in real milk matrix with concentration 3,74 ± 0,02 mg/l. The other microelements in the prepared eluate were at or below the limit of detection of the instrumental method. The obtained results were compared with the analysis of milk after microwave digestion by ICP-OES. However, these results were below the detection limit of the device too, only Zn with concentration 3,91 ± 0,16 mg/l was measured. For the future analysis of the selected microelements in milk by DGT technique, further optimization of the preconcentration technique is required, or use of a more sensitive instrumental method.
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Nutritional composition of different type of milk
Viznerová, Veronika ; Punčochářová, Lenka (referee) ; Diviš, Pavel (advisor)
The aim of this bachelor’s thesis was to compare selected methods of milk treatment for elementary analysis using the ICP-OES technique. Certified reference material ERM®-BD150 was used to validate the method, which was treated by mineralization, the addition of reagents and dispersion. The highest calcium yield during validation was determined to be 90,6 ± 8,6 % with the addition of Triton X-100 reagent. In the potassium analysis, the highest yield was determined to be 89,5 ± 5,2 % by wet decomposition. The highest yield of magnesium was determined to be 120,1 ± 1,1 % after microwave decomposition. Furthermore, the highest yield of sodium was determined to be 104,4 ± 4,8 % by wet decomposition and the highest yield of phosphorus was determined to be 98,6 ± 4,5 %. Based on the validation results, suitable methods were selected for the analysis of real milk samples (wet decomposition, acid dispersion, addition of Triton X-100 reagent). Samples of fresh cow's, goat's and sheep's milk from domestic breeding were used for the analysis. The highest concentrations of most elements were determined in goat 's milk, namely calcium to 1 733 ± 126 mg.kg-1, potassium to 1 840 ± 39 mg.kg-1, magnesium to 252 ± 77 mg.kg-1, copper to 1,41 ± 0,56 mg.kg-1, manganese to 0,54 ± 0,26 mg.kg-1 and zinc to 7,98 ± 1,33 mg.kg-1. The highest concentrations of sodium in sheep's milk were set at 515 ± 90 mg.kg-1, phosphorus at 1 440 ± 100 mg.kg-1 and zinc at 7,98 ± 1,33 mg.kg-1. The most iron was found in cow's milk, namely 5,27 ± 1,59 mg.kg-1. For ICP-OES analysis, the use of an acid dispersion appears to be the best method of sample preparation, as the concentrations of the measured elements were the highest. However, only macroelements and zinc were measured reliably. For the determination of other biogenic elements, it would be more appropriate to choose a more sensitive technique or preconcentration of the analyte in the sample.
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Vliv věku při prvním otelení na mléčnou užitkovost holštýnských dojnic v konkrétním podniku
Landová, Valentýna
The bachelor thesis dealt with the effect of age at first calving of Holstein dairy cows on their subsequent milk yield. In the literature section, the basic characteristics of Holstein cattle, milk yield, milk composition and the influences on milk yield were described. In addition, fertility and reproduction of cows were defined in more detail. The practical part took place on a farm located in the Central Bohemia region. A total of 52 Holstein dairy cows were included in the evaluation. The selected cows were divided into four groups according to their age at first calving (calved up to 21 months, 22-23 months, 24-25 months and over 26 months). The data from the performance monitoring of Holstein cows in their first lactation were used in this study. Milk performance parameters monitored included milk yield, fat, protein, lactose, urea and somatic cell count. The effect of lactation stage on the listed milk parameters was also monitored. The lowest milk production was achieved by cows calving at 21 months of age (29.74 kg milk). On the other hand, the highest milk yield was obtained by cows calved at the age of 26 months and above (33.52 kg milk). This difference was found to be statistically significant (p<0.05). Furthermore, a sta-tistically significant difference (p<0.05) was found between the average milk yield of cows calved at less than 21 months of age and those calved at 24-25 months of age. The effect of age at first calving did not have a statistically significant difference (p>0.05) on the other observed milk contents.
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Zhodnocení provozních a ekonomických faktorů ovlivňujících výkupní cenu mléka na konkrétní farmě na Ukrajině
Orlov, Bohdan
The bachelor's thesis discusses operational and economic factors that affect the purchase price of milk. We were interested in one particular farm in Ukraine. The price formation mechanisms could be different compared to the Czech Republic and, consequently, the European Union, which was interesting us. The monitored parameters mainly included: the amount of milk pro-duced, fat and protein content, takings depending on the quantity and quality of milk produced. We selected the subject (sample) by convenience sampling method. The company STOV im. Lesia Serdiuka, which is specified for the breeding of Holstein (Ukrainian black-and-white) and Ukraini-an red-and-white cattle, served as the object of the research. Data collection was carried out through telephone conversations and e-mail communication, the obtained data were subse-quently processed according to common mathematical and statistical methods. The results of the research indicate a strong direct-proportional connection between the purchase price of milk and the concentration of fat and protein, however, the total takings are affected more by the amount of milk produced than by the amount of components contained in it.
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Porovnání ekonomiky výroby mléka českého strakatého skotu na dvou farmách
Smolíková, Petra
This thesis deals with the comparison of the economics of milk production of Czech spotted cattle on two farms. The evaluation was based on three years of data from the farms. The results show that there are differences in milk yield and costs between the farms, which lead to differences in profits. The data was processed using tables and graphs to specify the economics of feed day, milk production, turnover per cow. The last part of the paper highlights the average percentage distribution of the cost of production of the enterprises. The total cost per feeding day, litre of milk and dairy cow was an amount ranging from CZK 7.82 to CZK 76.585.11 in the enterprises depending on the factor and enterprise under study. The main percentages of costs were for feed and bedding, on average The size of the holdings ranged from 378 to 520 cows, with daily milk yields of 16.58 to 24.32 litres of milk per cow in the years under review. The findings and recommendations for improving farm profitability are concluded.
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Výživa koz
Kopecká, Michaela
The aim of this paper is to introduce the main principles and types of feed in goat nutrition. The main focus of the work is on dairy goat nutrition and the influences on milk production. Goat milk is a raw material whose quality depends on nutrition. In addition to dairy goats, it also deals with feed composition and individual rations. As a result of this work, information on existing goat breeds, feeds suitable and unsuitable for goat nutrition and feed rations are sorted out. The composition of rations depends on several factors. The main distinction is the age of the animal. Baby goats are fed differently from adult goats. Another key factor is the physiological condition of the goats. Other factors influencing goat nutrition include the season, which determines the summer and winter rations. In order for nutrition to be comprehensive and achieve the desired results, all factors must be taken into account.
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Reprodukční a užitkové vlastnosti dojnic
Leznová, Sára
The aim of the bachelor thesis was to evaluate the reproductive and useful properties of dairy cows. The work deals with the comparison of performance parameters and reprodu-ctive properties of milked cattle. The first part summarizes the basic reproductive indica-tors. The next part of the thesis discusses milk and its content of components and its qua-lity, which is followed by the chapter on milk productivity. The production and consump-tion of milk is evaluated in the work both within the Czech Republic and worldwide. In the practical part, the following reproductive indicators were evaluated: Insemination in-terval, service period, insemination index and intermediate period. The level of selected reproductive and utility indicators was analyzed for individual groups of dairy cows ac-cording to the season in one year.
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Pozice a výkonnost zemědělského podniku v současném prostředí agrobyznysu České republiky
Hrdličková, Lucie
The diploma thesis focuses on the position and performance of the agricultural business in the current agribusiness environment in the Czech Republic. A selected agricultural com-pany, which is PROAGRO Radešínská Svratka, a.s., is characterized in the thesis. The business core of this company is crops, animal and other production. An important line of the agricultural business is the milk commodity and the production of biogas. Selected indicators of financial analysis were used to evaluate the economic situation of the company. Based on that, it has been concluded that the company is in an acceptable financial situation. It can respond appropriately to the stimuli from the outside environment through its strategic decisions. The thesis draws attention to the main milestones of strategic decisions and their causes. It also considers possible future threats.
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Technologie výroby a hodnocení jakostních parametrů bílých sýrů v solném nálevu
Mištová, Dominika
This thesis deals with the production technology and quality parameters evaluation of white brined cheeses. The characteristics, origins, technological procedures of production, and differences between them are described. The work aimed to carry out sensory evaluation and determination of physicochemical parameters. These criteria were identified for selected representatives of white brined cheeses available on the Czech market and for own samples produced under semi-operating conditions. A sub-objective was to compare both individual samples with each other and commercially available samples with the data given on the manufacturer's packaging. When comparing the results of the analysis with the data indicated on the package, the protein and fat content in both cases of commercially available samples was higher than declared by the manufacturer. On the other hand, the course of souring in the produced cheeses was insufficient. The titration results of the produced cheese samples differed by almost half from the cheeses purchased on the domestic market.
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