Search

Published After
Published Before

Search Results

  • Comparison of the sample preparation methods worked out for the examination of the element content of wine
    77-82
    Views:
    112

    The examination of the potentially toxic elements content of the wines is not easy task, because the most elements are in little concentration (mg kg-1 or μg kg-1) in the wine and the wines contain great amount of organic matrix. The efficient sample preparation is essential for the accurate determination of element content. The eim of our research was to determine which sample preparation method will be the most efficient in examination of wines with ICP technology. The examined wine sample was a 2008 Chardonnay from the Eger wine region. We did the sample preparation and analysis examination in University of Debrecen, Centre for Agricultural and Applied Economic Sciences, Institute of Food Science, Quality Assurance and Microbiology.
    We did the analysis examinations with ICP- MS (inductively coupled plasma mass spectroscopy). We always did the sample preparations and the examinations in three times rehearsal. The applied sample preparation methods: dilution with distilled water, open digestion and microwave digestion. 
    We were able to measure B, Al, Mn, Fe and Zn with only dilution and open sample preparation. In the smaller quantity present Sr and Ba were measurable in the wine in the case of all three methods well. We were able to measure the Co with dilution and open digestion method,  while Cr, Ni, and Te with only dilution method. In the case of arsenic we were not able to measure reliable result with dilution and open digestion method because of organic matrix and other components
    (alcohols, monosaccharides, polysaccharides, polyalcohols and inorganic salts). On the whole we are able to say that in the case of certain elements (B, Mn, Fe, Zn, Sr, Ba) the open digestion and dilution sample preparation is applicable well, however, in the case of certain elements (As, Al, V, Cr, Se, Mo, Cd, Hg, Pb) we have to develop the methods. It may be development of one of the way, if we develop sample preparation methods to examined element specifically and not
    to wine generally.

  • Selenium-speciation experiments from soil samples by accept of ionchromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS) method
    106-111
    Views:
    129

    In these days, selenium is one of the most investigated microelements. It has an important proven role in many vital processes. Selenium deficiency can play a role in the contraction of many diseases (e.g. cancer, heart diseases, etc.) and in the aggravation of their clinical aspect directly or indirectly. In this paper, we study the soil samples of an outdoor experiment for the conversion of the inorganic selenium salt that was spread out in different doses. The danger of the wash-out effect was also investigated. Our experiments showed, that most of the inorganic selenite transforms to selenate form during the years, and in this selenate form it moves to the deeper layers of soil.

  • Optimization of inductively coupled plasma mass spectrometer parameter’s to measuring arsenic and selenium
    59-64
    Views:
    159

    In the last decades an increased interest has been evolved about arsenic and selenium. The aim is to understand the environmental, agricultural and biological role of the these elements. In case of arsenic the mayor reasons are the relatively high concentration of arsenic in marine biota (mg kg-1) and the arsenic contaminated drinking waterbases of some Asian countries besides Hungary. The toxicity of higher level selenium content is also known, nevertheless selenium is essential for some biological functions. Considering its esssentiality, in our country the insufficient selenium intake rate couse lack of selenium. Measuring the concentrations of these elements are cruital but not satisfactory information, but the speciation, that is the form of an element presented in a sample is also required. 
    In both cases the most suitable method to determine concentration is the inductively coupled plasma mass spectrimetry. My objective was to optimase the changeable parameters of the ICP-MS for reaching the lowest (the best) detection limit. For this porpuse I have investigated the effect of parameter change on nett signal intensity and relative signal intensity. With the optimased parameter settings the limit of detection for arsenic and selenium were determined, which are 0,032 ng cm-3 for arsenic, and 0,097 ng cm-3 for
    selenium.

  • Effect of molybdenum treatment on the element uptake of food crops in a long-term field experiment
    75-79
    Views:
    123

    Molybdenum, as a constituent of several important enzymes, is an essential microelement. It can be found in all kind of food naturally at low
    levels. However, environmental pollution, from natural or anthropogenic sources, can lead to high levels of the metal in plants. Our study is based on long-term field experiments at Nagyhörcsök, where different levels of soil contamination conditions are simulated. Plant samples were collected from the experiment station to study the behavior of elements: uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop. In this study, we present the effect of molybdenum treatment on the uptake of other elements. Molybdenum is proved to be in an antagonist relationship with copper and sulphur, while molybdenum-phosphorus is a synergist interaction. However, in most of the plants we studied, increasing molybdenum-treatment enhanced cadmium uptake. We found the most significant cadmium accumulation in the case of pea, spinach and red beet. 

  • Determination of the validation parameters of inductively coupled plasma mass spectrometer (iCP-mS): response curve linearity in the case of arsenic and selenium
    67-71
    Views:
    130

    In the field of elemental analysis inductively coupled plasma mass spectrometers (ICP-MS) have the best sensitivity that means the lowest limit of detection, subsequently their applicability for the detection of essential and toxic elements in foods and foodstuffs is prominent. For the most elements could be measured the detection limit is between μg kg-1 (ppb) and ng kg-1 (ppt) e.g. for arsenic and selenium.

    Considering an analytical task (sample type, analytes and their concentration, pretreatment procedure etc.) the applicability of an analytical method is determined by its performance characteristics. The purpose of validation is to ensure that the method would be used fulfills the requirements of the given task. In this article we describes one of the performance characteristics, the linearity, and the whole validation procedure aims measurement of arsenic and selenium in foodstuffs by inductively coupled plasma mass spectrometer (Thermo XSeries I.); but because of the limited number of pages the results are demonstrated only for arsenic.

    The linearity of calibration was evaluated in three concentration ranges (0.1–1 μg l-1; 1–10 μg l-1; 10–50 μg l-1), with nine line-fit possibilities (without weighting, weighting with absolute or relative deviation; with or without forcing the curve through blank or origin) and different methods (graphical examination, correlation coefficient, analysis of variance).

    The best method to ensure the linearity of correspondence between signal and concentration was the ANOVA test. In view of calibrations it was found that the range of 10–50 μg l-1 could be regarded as linear with four line-fit possibilities, and was non-linear between 0.1–1 μg l-1 and 1–10 μg l-1.

  • SIM Samples Investigation by Statistical Methods
    194-197
    Views:
    60

    The assessment of the present condition of the soil is very important, because the accession of the number of the European Union members is in the near future. This can be the base of the modern agrarian environmental management programme. The assessment must be objective, detailed and analyse the processes in the soil.
    Respecting the above causes was decided to create an Environmental Information Monitoring System. This system consists of more parts. One of them is the Soil Information Monitoring System (SIM). This system started to work in 1992.
    This system has two functions. Creating and actuation is obligatory from the international contracts, on the other hand the public SIM has very important role in the conservation of the soil.
    The SIM territorial measuring grid consists of 1236 measuring points. These points are representatives. The distributions of the points by the types of soil attend the variety of the types of soil of the country.
    The investigated elements in 6 types of soil were in our experiment (the group of scandium and the lanthanide series elements). There are 6 elements above the detection limit (Gadolinium, Neodymium, Praseodymium, Scandium, Samarium, Yttrium).
    The Neodymium concentration is 2 times higher than the content of Gadolinium and Yttrium.
    The Neodymium concentration is 4 times higher than the content of Praseodymium, Scandium and Samarium.
    In the case of Dysprosium, Europium, Lutetium, Terbium, Ytterbium the concentrations were below 1 mg/kg.

  • Effect of molybdenum treatment on uptake of plant and soil molybdenum content in a field experiment
    117-122
    Views:
    113

    Molybdenum is not a well-known microelement, but being a constituent of several important cellular enzymes it is an essential microelement. Molybdenum occurs in all foods, but at very low levels. There does not appear to be any particular foods or types of foods, which in the absence of extrinsic factors, naturally have high levels of molybdenum. However, environmental pollution, from natural or anthropogenic sources, can lead to high level of the metal in plants.
    Our study is based on the long-term field experiments of Nagyhörcsök, where different levels of soil contamination conditions are simulated. Soil and plant samples were collected from the experiment station to study the behaviour of molybdenum: total concentration, available  concentration, leaching, transformation, uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop. In this work we present the results of maize and peas and the soil samples related to them.
    According to our data molybdenum is leaching from the topsoil at a medium rate and it appears in the deeper layers. In the case of plant samples we found that molybdenum level in the straw is many times higher than that is in the grain, so molybdenum accumulates in the vegetative organs of the plant. The data also show differences in the molybdenum-uptake of cereals and Fabaceae (or Leguminosae).

  • Opportunities for improving the nutritional value of cereal-based products
    275-278
    Views:
    158

    We set up experiments for improving the nutritional value of cerealbased products. Our aims were to decrease the energy content of bakery products with the mixing of plant originated raw materials and byproducts with high fibre contents, and we have evaluated the effect of sodium-chloride on the physical properties of bakery products. We found that the apple pomace, the byproduct of juice production, is excellent for increasing of fibre content of bakery products and the further aim of investigation is to develop economical ways of hygienic byproduct handling and purification. Our experiments, evaluate the bakery use of triticale, have significant achievements and the breads made from triticale flour and whole-grain are commercially available nowadays. Our investigations included the possibilities of decrease of toxin contamination of cereals and our results can form a part of risk estimation systems after further experiments .

  • Effect of Selenium Supplementation on in vitro Radish and Green Pepper Seedlings Germination
    149-155
    Views:
    132

    Selenium (Se) is an essential trace element for animals, microorganisms and some other eukaryotes. It has become increasingly evident that Se plays a significant role in reducing the incidence of lung, colorectal and prostate cancer in humans. Although there is evidence that selenium is needed for the growth of algae, the question of essentiality of Se in vascular plants is unresolved. Therefore Raphanus sativus (Se accumulator) and Capsicum annuum (non Se accumulator) were treated with 0-200 mg/l natrium-selenate. The results showed that lower (2 mg/l) concentration natrium-selenate increased the fitomass and total antioxodant capacity in seedlings.

  • Studying of quality parameters of Hungarian and Greek honey samples
    147-153
    Views:
    146

    Honey has been a valuable food for mankind since ancient times. It was the only sweetener until the start of industrial sugar mass production. Honey plays an important role in our nutrition and its positive effects on health are well-known. The quality of Hungarian honey is perfect, so it is very important to safeguard and monitor its quality continuously and to build up a good traceability and quality assurance system. For such a system, it is necessary to study the nutritional properties and the origin of different honey samples. In our study, we study Hungarian and Greek honey.

  • Element content analyses in the Institute for Food Sciences, Quality Assurance and Microbiology
    203-207
    Views:
    110

    The role of chemical elements to ensure and promote our health is undisputed. Some of them are essential for plants, animals and human, others can cause diseases. The major source of mineral constituents is food, drinking water has a minor contribution to it, so the knowledge of elemental intake through food is crucial and needs continuous monitoring and by this way it promotes the food quality assurance and dietetics.
    With the evolution of spectroscopic methods increasingly lower concentrations could be determined, so the elemental composition of a sample could be more precisely and fully described. Due to the results the gathered knowledge up to the present is supported and new observations can be done helping us to understand such complex systems as biological organisms are.
    The quality of a food is determined by the full process of its production, consequently it starts with agricultural production so elemental-analysis usually cover the whole soil – plant – (animal) – food chain, by this way the „Fork-to-Farm” precept is true in elemental analysis field also.
    The history of elemental analysis in the University of Debrecen, Centre for Agricultural and Applied Economic Sciences, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Food Processing, Quality Assurance and Microbiology goes back to 1980s when the so called Regional Measurement Central gave the background for research. The continuous deployment resulted in an obtain of an inductively coupled plasma atomic emission spectrometer (ICP-AES) in 1988, which extended the scope of examinations due to its excellent performance characteristics
    compared to flame atom absorption (FAAS) and flame emission spectrometers (FES). The instrumental park retain up to date correlate to the developing analytical techniques due to acquiring a newer ICPAES in 1998 and an inductively coupled plasma mass spectrometer in 2004 – which sensitivity is three order of magnitude better compared to ICP-AES. The Institute supports the work with its own ICP-AES and ICP-MS since 2011. 

  • Application of the Collision Cell (CCT) in the ICP-MS Analytical System
    120-125
    Views:
    130

    Our laboratory has seen a sharp rise in the number of requests for the analysis of smaller and smaller concentrations of elements from foods, plants, soil, organic fertiliser, irrigation and ground water, sewage, sewage sludge, raw material of food, as well as human and animal origin samples. From the above elements the inductively coupled plasma mass spectrometer is capable of analysing the smallest concentration of elements. Our method of analysis is to use our ICP-MS instrument, together with a ICP-MS with Collision Cell Technology (CCT). The CCT method has better detection limit, with 1-3 magnitudes, compared to the normal ICP-MS analytical method. The CCT has better detection limits mainly for the following elements in the periodical system: analysis of arsenic, selenium, germanium, vanadium and chromium. Additionally a collision cell can be applied for the analysis of silicium, sulphur, zink, copper, iron, calcium, magnesium and potassium in smaller concentrations.

  • Effect of molybdenum treatment on the element uptake of plants in a long-term experiment
    121-125
    Views:
    101

    Molybdenum as a constituent of several inmportant enzymes is an essential micorelement. It can be found in all kind of food naturally at low level, however, environmental pollution, from natural or anthropogenic sources, can lead to high level of the metal in plants. Our study is based on the long-term field experiments of Nagyhörcsök, where different levels of soil contamination conditions are simulated. Plant samples were collected from the experiment station to study the behaviour of elements: uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop.
    In this work we present the effect of molybdenum treatment on the uptake of other elements. Molybdenum is proved to be in an antagonist relationship with copper and sulphur, while molybdenum-phosphorus is a synergist interaction.
    However, in most of the plants we studied increasing molybdenum-treatment enhanced cadmium-uptake. We have found the most significant cadmium-accumulation in the case of pea, spinach and red beet.