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This article is the second part of the review of the studies on nutrition in Polish preschool children. In the first part, studies on preschool menus assessment were presented and summarised, whereas this article reviews the studies on the assessment of foods and meals prepared at preschool. The aim of this review was to present and summarise the results of the studies on the assessment of meals prepared for children at preschool based on the reports from the preschool food storeroom, the studies on chemical analysis of sample meals served at preschools and the studies on comparison of the results of chemical analysis to the results obtained by calculations obtained from computer programmes. The results of the studies on the assessment of meals prepared for children at preschool using various methods confirm most of the findings from the studies on the assessment of preschool menus. It is necessary to carry out more studies on energy and nutrient content assessment of preschool meals determined by chemical analysis of sample meals in order to provide more accurate information about the real nutritional value of meals served to children at preschool. It is essential to update the Polish food composition tables to enable more precise calculations of nutritional value of the meals planned for children at preschools which will improve the possibility of adjusting preschool meals to the real needs of both 3-year-old and 4-6-year-old children during their stay at preschool.
The process of analytical signal generation in chemical sensors such as ion-selective electrodes, ion-sensitive field effect transistors and fibre optic sensors is described. The principle of operation of these sensors is explained with respect to the signal conversion from the concentration of the analyte into the changes in analytical signal obtained from the sensor. Some general considerations about chemical sensor design are also given.
This reviev describes the methods of preparation of carbon and carbon-mineral adsorbents by carbonization of different organic materials. The methods of carbon preparation were subdivided into two groups: preparation of sorbents on a large industrial scale, and for laboratory (chromatographic and adsorption) purposes. It also demonstrates the specific properties of some carbon adsorbents as well as the possibilities of their utilization for the purposes of environmental protection (sorption of organic pollutants from water wastes) and for analytical purposes especially for gas (GC) and liquid (HPLC) chromatography. This article also shows some possibilities (e.g. consumed catalysts, sorbents used in food and paper industries, from removal of oil from waste waters, etc.) of preparing different, mainly carbon-mineral adsorbents.
Background. Numerous studies attest to the role that inappropriate food product groups in the human diet, including children and adolescents diet, leading to abnormal intakes of many important nutrients, such as minerals. Objectives. These studies were undertaken to assess the coverage of the recommended values for chosen minerals by 205 children and adolescents between the ages of 4 and 20 years, grown up in Krakow orphanages. Materials and Methods. Sodium, magnesium, zinc, iron, copper, calcium and potassium concentrations in 112 diets of children and adolescents from 7 selected orphanages in Krakow in every season of the year were performed using AAS method. Results obtained were compared to recommended standards in Poland. Results. Intakes of calcium and potassium were usually too low whilst adequate levels of dietary magnesium and calcium were seen only for the youngest children. Recommended dietary levels of zinc were met in all cases and mostly also for iron and copper. Sodium intakes were however excessive. Conclusions. The study demonstrates that regular a monitoring and adjusting of the diet is necessary for the assessed children and adolescents in order to correct dietary abnormalities.
Buffalo’s milk protein products, total milk proteinate (TMP), rennet casein, and lactic acid casein were studied. The chemical composition was determined and some properties (water and oil absorption capacity, emulsion activity, foam expansion, and buffer capacity) of these products were also determined. The results indicated some differences in the chemical composition and electrophoresis bands of protein between total milk proteinate, rennet casein and lactic acid casein. The TMP was characterised by the lowest ash and moisture contents with highest protein contents compared to the other protein products. There is no remarkable effect of drying methods on the chemical composition within each type of protein products. Total milk proteinate contains some whey proteins which are high in alanine, cystine when compared with rennet casein. Lactic acid casein had high contents of amino acid proline. On the other hand, the rennet casein had a low content of sulfur containing amino acids cysteine and methionine. Differences between total essential amino acid (TEAA) of total milk proteinate and lactic acid casein were significantly (p<0.05) higher than those of rennet casein. Freeze dried total milk proteinate exhibited excellent foaming and emulsifying potential when compared with oven-dried caseinate. For all protein types, the maximum WAC can be seen for freeze-dried milk proteinates, whereas the minimum value was for oven dried rennet casein. The minimum value of emulsion capacity and surface tension was obtained at pH 4.5 and 2.5 in all types of proteinates, whereas the maximum values were found at pH 10.5. Relative viscosity of TMP solutions was higher than those of rennet and lactic acid casein. However, relative viscosity values tended to decrease with lowering or increasing the pH values of the solutions from the neutral pH value. Calorimetric analysis showed two major enthalpy changes in the tested caseinate samples. The first change occurred at peak temperature range of 92.2°C to 100.8°C for the moisture removal, while the second change occurred between 273.9°C and 314.6°C for protein degradation. The enthalpy values ranged between 218.3 to 268.4 J/g for moisture removal. Total milk proteinate showed two major peaks for protein degradation indicating the presence of whey proteins and milk caseins.
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