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  • 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:
    129

    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.

  • Comparative analysis of sample preparation methods to determine the concentration of arsenic in soil- and plant-samples
    167-170
    Views:
    130

    Arsenic contamination of the fields and groundwater is a global problem. Alföld is the most affected area in Hungary. Irrigation witharsenic contaminated water, and crop production on the contaminated soil can cause a food safety problem, because arsenic is easy taken up by the cell of the plant roots. To prevent this, very important to monitoring the arsenic content of soils and plants. Inductively coupled plasma mass spectrometry (ICP-MS) is a fast, easy method to determined the concentration of minerals in the case of plant and soil samples The analytical methods can give reliable, results if the analytical process, including the sample preparation method, is the best. The objective of this study was to compare 3 type of sample preparation method which was dry ashing, wet digestion in open system, and microwave digestion. As a result of our experiement shows the microwave digestion is the appropriate method to determined the arsenic content of soil samples. In the case of plant samples we can use wet digestion in open system or microwave digestion as a samle preparation method.

  • 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.

  • Customer Relationship Systems and Business Models
    99-106
    Views:
    98

    The object of this study is a comprehensive review of customer relationship management (CRM) systems applied increasingly in several fields of economy. The CRM is not merely a subsequent software technology and application in the field of Business Intelligence, but rather a novel, comprehensive customer-centric approach to an organization’s philosophy in dealing with its customer for the sake of realization of short- and long-range business target contrary to the traditionally widespread productcentric approach. The object of the study, following a short
    synopsis of the theoretical and practical aspects of the CRM systems, is to analyse the range of the actual and potential users and to survey the CRM market. It will be analysed the scope of CRM supported business activities and processes, the terms and possible methods of launching and will be outlined a feasible model, too. The aim of conspectus of different CRM strategies (layers) is to reveal the urging need of turning approach in the field of management.

  • Interpretation of sustainability in the utilization of renewable energy sources
    61-64
    Views:
    100

    The utilization of renewable energy sources (res) is crucial regarding to sustainable reconstruction of energy systems. The target is a balanced, sustainable development of Hungarian energy management considering equally the ecological, social and economic aspects. There are many different technologies of utilization of res varied by sources, conversion processes, size and products. The comparison of each technology and their sustainability assessment are required by the importance of efficient remodeling of energy infrastructure. The group of attributes was composed by numerous important parameters in the course of our analysis with the choice experiment (ce) methodology. The estimation of each attributes’ influence on the individual’s preferences and choices was possible by this method and the preferences of the statistical population was concluded. So thus the utility derived from each attribute was estimated. The result of the ce analysis for the population of experts is demonstrated in the current phase of our research.

  • Analytical overview of dairy industry in the Poltava region, Ukraine
    47-51
    Views:
    122

    The author presents essential characteristics of the state and place of Poltava region in it. The study aims at identification and description of latest trends in Ukraine’s and Poltava’s dairy industry. The author stresses an important place of the dairy industry in the agriculture of Ukraine, and particularly in the Poltava region. This article also presents the information of main indicators of dairy industry of Ukraine in the comparison with other countries of the World. It describe sources of forming the main agricultural products and directions of their use for the calendar year, data on per capita consumption of main dairy products in Ukraine and the Poltava Region and per capita average daily consumption of basic micro- and macro elements in foods. The study contains basic indicators which characterize the social and economic state of agriculture in Ukraine and its regions for 1990–2012. There are also the data of gross production and main kinds of dairy products per capita and as well as some indicators of livestock’s productivity and so on.

    The goal of the article is to describe the complex evaluation of the achieved level of milk production, consumption of milk and dairy products in Ukraine and the Poltava Region, to show the specifics of the national dairy cattle breeding, identifying the main challenges in it.

  • Information and Communication Technologies in tourism
    49-53
    Views:
    142

    Technological progress and tourism have gone hand in hand for years. Information communication technology (ICT) and tourism are two of the most dynamic motivators of the emerging global economy. Tourism can be considered as one of the most profitable sectors of the Hungarian economy, and in rural areas it is often the only successful economic activity.
    Development of ICTs and the expansion of the Internet have changed dramatically in the past few decades. This process is noticeable in
    Hungary, as well. Platform of tourism increasingly get to the Internet nowadays, which is vitally important because tourism is an information-intense industry. Therefore, it is critical to understand changes in technologies in order to maintain the crucial role of this sector in the Hungarian economy.
    The aim of my study is to support the significance of tourism in Hungary and especially in the North Plain Region with the help of statistical data. Then, I try to show how ICTs appear in this sector and emphasize the role of these tools with some concrete examples.

  • Selenium speciation analysis of selenium-enriched food sprouts
    23-28
    Views:
    180

    In this present study, we prepared selenium-enriched pea and wheat sprouts. During our research we aimed not only to measure the total selenium content of the sprouts but to identify different selenium species.

    Scientifical researches show why the analytical examination of different selenium (Se) species is necessary: consumption of all kind of Se-species is useful for a person who suffers in selenium deficit, while there is significant difference between effects of different Se-species on person, in whose body the Se-level is just satisfactory. Biological availability, capitalization, accumulation, toxicity of Se-species are different, but the main difference was manifested in the anti-cancer effect of selenium.

    During our research selenium was used in form of sodium selenite and sodium selenate, the concentration of the solutions used for germination was 10 mg dm-3. Control treatment meant germination in distilled water. Total selenium content of sprout samples was measured after microwave digestion by inductively coupled plasma mass spectrometry (ICP-MS). Different extraction solvents were applied during sample preparation in order to separate different Se-species (0.1 M and 0.2 M HCl or 10 mM citric acid buffer). We wanted the following question to be answered: Which extraction solvent resulted the best extraction efficiency? Selenium speciation analysis of sprout sample extracts was performed by high performance liquid chromatography with anion exchange column, detection of selenium species was performed by ICP-MS.

    Evaluating our experimental results we have been found that significant amount of selenium of inorganic forms used during germination transformed into organic selenium compounds. There was difference between the amount of Se-species in pea and wheat sprouts and selenium uptake and repartition of selenium species were depended on Se-form used during germination. In addition the chromatogram analysis made us clear as well, that the citric acid solvent proved to be the most effective extraction solvent during sample preparation int he view of organic Se species.

  • Food allergy, safety and analytics
    323-326
    Views:
    103

    The food allergy is a hypersensitivity reaction against naturally occurring proteins in food. These types of disease can cause not only personal inconvenience to the patient but serious health, food safety and food analysis, social-economic problems. The only effective treatment for these illnesses is a life-long diet avoiding the allergenic foods or components of food. In the interest of the patients’ health 14 allergenic components must be labeled on the food packaging. To meet the requirement of regulation reliable and valid analytical methods are necessary which for the most allergenic foods are not available.

  • Economic questions of precision maize production on chernozem soil
    293-296
    Views:
    122

    It is one of the main topical objective to establish the conditions of sustainable farming. The sustainable development in crop production also calls for the harmony of satisfying human needs and providing the protection of environmental and natural resources; therefore, the maximum consideratio of production site endowments, the common implementation of production needs and environmental protection aims, the minimum load on the environment and economicalness. Precision farmin encompasses the farming method which is adjusted to the given production site, the changing  technology in a given plot, the integrated crop protection, cutting edge technologies, remote sensing, GIS, geostatistics, the change
    of the mechanisation of crop production, and the application of information technology novelties in crop production. Modern technology increases efficiency and reduces costs. The efficiency of crop production increases by reducing losses and the farmer has access to a better decision support information technology system. In addition, we consider it necessary to examine the two currently most important economic issues: “is it worth it?” and “how much does it cost?”. During the analysis of agricultural technologies, we used the precision crop production experiment database of KITE Zrt. and the Institute for Land Utilisation, Regional Development and Technology of the Centre for Agricultural and Applied Economic Sciences of the University of Debrecen.
    During our analytical work, we examined three technological alternatives on two soil types (chernozem and meadow). The first technology is the currently used autumn ploughing cultivation. We extended our analyses to the economic evaluation of satellite navigationassisted ploughing and strip till systems which prefer moisture saving. On chernozem soil, of the satellite-based technological alternatives, the autumn ploughing cultivation provided higher income than strip till. In years with average precipitation supply, we recommend the precision autumn ploughing technological alternative on chernozem soils in the future. On meadow soil, the strip till cultivation technology has more favourable economical results than the autumn ploughing. On soils with high plasticity – considering the high time and energy demand of cultivation and the short amoung of time available for cultivation – we recommend to use strip till technologies. 

  • Analysis of sweet corn nutritional values using multivariate statistical methods
    103-108
    Views:
    202

    Processing large amounts of data provided by automated analytical equipment requires carefulness. Most mathematical and statistical methods have strict application conditions. Most of these methods are based on eigenvalue calculations and require variables to be correlated in groups. If this condition is not met, the most popular multivariate methods cannot be used. The best procedure for such testing is the Kaiser-Meyer-Olkin test for Sampling Adequacy. Two databases were examined using the KMO test. One of them resulted from the sweet corn measured in the scone of the study, while the other from the 1979 book of János Sváb. For both databases, MSA (measures sampling adequacy) was well below the critical value, thus they are not suitable e.g. for principal component analysis. In both databases, the values of the partial correlation coefficients were much higher than Pearson’s correlation coefficients. Often the signs of partial coefficients did not match the signs of linear correlation coefficients. One of the main reasons for this is that the correlation between the variables is non-linear. Another reason is that control variables have a non-linear effect on a given variable. In such cases, classical methods should be disregarded and expert models better suited to the problem should be chosen in order to analyse the correlation system.

  • Wine adulteration and its detection based on the rate and the concentration of free amino acids
    139-151
    Views:
    301

    Following the definition of wine adulteration, the authors briefly review its history from ancient times to present day and describe the methods that are applied for adulteration of wine from the historical point of view. More space is devoted to the Hungarian wine adulteration and to the detailed reports of the early methods, which attempted to discover fake wine. It describes in detail the current situation of wine adulteration and the fight against counterfeiting. The second half of the review article presents some examples of the analytical chemistry techniques with which fake wines can be detected. In doing so, priority is given to the discussion of high performance liquid chromatography and gas chromatography applications. The end of this paper describes the free amino acid content of wines, and the possibilities of using the results for detection of wine adulteration.

  • Economic questions of maize production on different soil types
    289-292
    Views:
    103

    The requirements and objective of cultivation are in constant change. For example, different cultivation systems are developed for the purpose of soil protection, the preservation of its moisture content and on soils with various precipitation supply or production site conditions. Traditionally, one of the most important cultivation aims is crop needs. Further cost saving in fertilisation and crop protection can only be achieved by reducing the quality and quantity of production or it cannot be achieved at all. Furthermore, the costs can be significantly reduced by means of the rationalisation of cultivation. Energy and working time demand can also be notably reduced if ploughing is left out from the conventional tillage method. The key requirement of economicalness is to perform the cultivation at the optimal date, moisture level and the lowest possible cost.
    Within production costs, the cost of cultivation is between 3–17%, while they are between 8–36% within machinery costs. It is the vital condition the usability of each technological method to progressively reduce costs. Our evaluation work was carried out with the consideration of the yield data obtained from cooperating farms and the experiment database of the Institute for Land Utilisation, Regional Development and Technology of the Centre for Agricultural and Applied Economic Sciences of the University of Debrecen. Three technological methods (ploughing, heavy cultivator and loosening tillage) were used on several soil types which differ from in terms of cultivability (chernozem, sandy and sandy clay soils) from the economic/economical aspect. We examined the sectoral cost/income relation of maize production as an indicator plant. The maize price during the analytical period was 45 thousand HUF per t. On chernozem soils, the production of maize can be carried out on high income level, while maize production on sandy soils has a huge risk factor. The role of cultivation is the highest on high plasicity soils, since they have a huge energy
    demand and the there is a short amount of time available for each procedure in most cases.

  • 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.