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Optimization of inductively coupled plasma mass spectrometer parameter’s to measuring arsenic and selenium
59-64Views:218In 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. -
A tárolási feltételek hatása a kukorica Fusarium fertőzöttségére és toxin szennyezettségére
28-32Views:289Corn samples harvested in 1997, 1998 and 1999 from different soil types were stored at different conditions (temperature, moisture content, state of kernels) for six months. The Fusarium contamination was examined by plate dilution method and the amount of mycotoxins (F-2, T-2, HT-2, DON, DAS) were determined applying HPLC method immediately after harvesting and in the third and sixth month of storage. The aim of our study was to find correlation between the ecological factors, storage conditions and the examined parameters mentioned above, as well as to prove them statistically. According to the examinations carried out after harvesting we could state that the soil type had no effect on the parameters. Analysing the effect of the years we found considerable differences. The Fusarium infection of corn samples in 1998, while the toxin contamination in 1999 was the highest. The results of storage experiment show that year (number of microscopic fungi, F-2, T-2, HT-2, DAS and total toxin content) and moisture content of kernels (F-2, T-2, and total toxin content) have a significant effect on the examined parameters. We could prove the effect of temperature on the T-2 content (samples with natural moisture content) and DON content (samples with 14% moisture content). Higher values were found at higher temperature storage. The ratio of damaged kernels influenced the DON concentration in the non- wetted samples and the number of microscopic fungi in the wetted samples.
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Qualitative detection of genetically modified organisms in plant samples
309-313Views:177We analysed the GMO content of corn samples by polymerase chain reaction following the appropriate optimization of the reaction. The analysis included two main steps: extraction of DNA from the sample, and detection of the GMO content by polymerase chain reaction. The polymerase chain reaction is an in vitro method to multiply chromosomatic or cloned DNA (cDNA) sequences through the enzymatic pathway. The reaction is sensitive enough to produce DNA in sufficient amount for the analysis from a single DNA. We identified the PCR products by agarose gel electrophoresis. When optimizing the reaction, the MgCl2 concentration, reaction time and temperature have to be taken into consideration. The temperature of the anellation has to be increased until the highest specificity and yield is reached. If the temperature of the anellation is too high, the primer is linked to non-specific sites as well; in the gel visualization, more lines can be seen at one sample. If the temperature of the anellation is too high, the primer is insufficiently linked or is not linked at all (too few lines in the gel visualization). After optimization, the GMO content in the unknown sample can be determined along with the appropriate positive and negative controls.
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Effects of Site on Winter Wheat Quality 2002/2003
100-107Views:140The demand of modern societies for high food quality is evident. Thus, it is important for agriculture to produce row materials that are valuable for nutrition and have favourable characteristics for food processing. For this we need a knowledge about the factors which determine the quality of products. One of the main features of plant production is the “immobility”. This way the characteristics of the field influence the quality of the product, like example winter wheat, which is the main cereal in Hungary and Europe.
The Concordia Co. has charged the Central Laboratory of Debrecen University, Agricultural Centre with laboratory testing of the 2002/2003 winter wheat crop. The samples consist of thirteen winter wheat varieties from six different sites under the same cultivating conditions. Therefore, the important wheat quality factors were analysed solely against site conditions with the use of Győri’s “Z” index, which contains these parameters.
Soils were tested first. In this experiment excepting the negligible differences between the sites, there were no linear relations found between quality factors, productivity and soil features. The case is the same with the relation between precipitation, temperature and quality parameters. However, it must be noted that additional soil analyses are required to interpret the extreme results obtained from Karcag.
The calculated Győri’s Z-index shows relative stability concerning certain varieties, although considerable deviation can be found in varieties related to the sites. According to these results, it can bestated that winter wheat quality was not linearly influenced by soil and weather in the 2002/2003 vegetation period. As the same cultivation technology was used in the experiment, the index was determined by genetic features. It must be noted that these findings are relevant only to this experiment. -
Selenium-speciation experiments from soil samples by accept of ionchromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS) method
106-111Views:212In 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.
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The examination of alveographical parameters of winter wheat varieties
87-91Views:157Nowadays, many methods have been worked up in the interests of objective expression of winter wheat rheological quality. These define wide spectrum in view of their complexity and apparatus claim. The needs for the methods are definitely increasing in Hungary, too. It is very important to get acquainted with the alveographical quality and qualification and also their using in wide range.
In our research we examined the alveographical parameters of 12 winter wheat varieties in Szeged (in Hungary) on the basis of the results in three years (2005-2007).
We established with correlation analysis that there is no statistical relation between the alveaographical W and G values. The other alveographical parameters have significant correlation. -
Changes of Quality of Winter Wheat During Maturing
105-112Views:129We analysed the flour of two winter wheat varieties to determine the effect of maturity state and grain position in the ear on the element composition of flour. Samples were taken from the 14th to the 42th day of anthesis. Ear samples were cut into three (basal, central and apical) parts, the trashed grains were milled, and the element compositions of the flours were determined.
We found that the grain position within the ear has an effect on flour element content. Flours of apical grains had lower nitrogen, phosphorus and sulphur contents than flours of central and basal grains. The nutrients can be divided into two parts, based on the formation of element content during maturation. Nitrogen, sulphur and copper contents changed continuously during maturity, while the P, K, Ca, Mg, Mn, Sr and Zn contents decreased until a specific value and became nearly constant in the second half of maturity. We found that – although the nitrogen concentration of flours changed continuously – the amount of nitrogen in the flours reached a constant value for the second half of maturity. -
Examination of extensographical parameters of winter wheat (Triticum aestivum) flour
109-115Views:141In the trade of the European Union principally the analysis of alveographical and extensographical parameters mean the acceptance system.
In the present study we analysed the extensographical parameters of 10 winter wheat varieties breed by the Cereal Research Non Profit Company with Brabender extensigraph and we made a comparison, correlation among the results. The examinations with Brabender the following among: show the GK Kalász and the GK Élet varieties show high resistance of extension and the GK Petur variety produces high extensibility. The GK Garaboly has shown low extensibility and energy. The other parameters had different values in the examined three years. The measurings with SMS2 Texture Analyser show middle positive correlation between extensibility and subarea. There are weak correlation between at the significantial level in the 90, 135 resistence of extension by Brabender and by SMS2 Texture Analyser and in the 45 extensibility by Brabender and by SMS2 Texture Analyser of relaxed dough. There is no correlation among other parameters. -
Following-up organic pollutants in the course of producing foods
244-248Views:159We analysed the raw materials in various food products, including additives, carrier solvents and end product for several selected organic pollutants. We analysed these food products for the type of chlorinated hydrocarbon pesticides, polychlorinated biphenyls and other currently used pesticides.
We analysed three product categories: bakery products, canned mushroom and meat products. The analysis of the bakery products and of the canned mushroom did not conclude in positive findings, which means that these products contained the agents given during the production of the product and the environmental pollutants in undetectable low concentration.
However, the results for meat and fish products indicate that polychlorinated compounds are persistent and are of a lipophyl character, as some of these components have been detected in these food products, the concentration of the PCBs were detected in the range of 9.8-24 μg/kg. -
Study of traditional folk foods from the point of view of nutrition in Hajdú-Bihar County
47-51Views:141Healthy nutrition is one of the major topics of our days. The occurrence of the so called “civilization diseases” is increasing continuously as a result of the changes in our nutritional habits and life-style. It was thought that folk nutrition at the beginning of the 19. Century had several beneficial effects on health. For this reason it was decided to study the food and nutritional habits of the population of Hajdu-Bihar County around the 1930s on the
basis of literary sources to see how well they do match with modern requirements of healthy nutrition. -
Results of Sulphur Fertilization Experiment with Oilseed Rape
174-178Views:108The rape is definitely a sulphur-demanding crop, which yield and the quality of its oil is threaten by the emerging shortage of sulphur nowadays. We made sulphur fertilising trials on two places in the northeastern rape growing area (in Felsőzsolca and Mezőkövesd), in the season 2001/2002. We compared the result the 5 five treating set in 2 repeats on brown forest soil with the results of the control plots. We used FitoHorm 32 S sulphur solution as sulphur fertiliser, with the dose of 3, 6 and 10 litres per hectare, as well as the joint effects of sulphur and boron; and the effect of boron alone. On the assessment of our results we looked for relation between the sulphur fertilising, the seed production, the oil content and the protein content.
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Results of foliar treatments on Sugar beet (Beta vulgaris L.)
303-308Views:131The yield and quality of the sugar beet are mainly determined by the plant production system, thus we studied the effect of mineral fertilization. Our field trials were carried out in 2005 and 2006 in Hajdúböszörmény, at two sites. We studied the effect of sulphur (Cosavet DF), copper (Kelcare Cu) and two foliar nutrients with high active agents. Treatments were replicated four times.
We took root samples at 4 week intervals, starting in August. The quality of root (sucrose, potassium, sodium and alfa-amino N content) was determined from filtrated beet broth, by an automatic beet laboratory system, called VENEMA.
We found that the crop and the sugar yield were significantly influenced by the foliar treatments in both of the two years. -
Effect of the Cropping Year on the Quality of Winter Wheat
89-95Views:161We examined the formation of quality parameters of winter wheat in a small plot variety comparison experiment from four cropping years. Our aim was to estimate the year effect on several quality parameters of winter wheat.
We established in relation to the distribution of precipitation of the examined years that the years 1997 and 2000 were behind the thirty year average typical precipitation of this site both in the case of the whole vegetation period and the spring and summer. It was unfavourable for qualitative wheat production. 1998 and 1999 were good for cropping considering the amount and distribution of rainfall.
Examining the formation of quality parameters we found that the baking value was maximum in 1997, with a moderate amount of normal distributed rainfall for the examined varieties. The mid-late maturating varieties showed better baking value in drought years than in wet years. In the case of the wet gluten content, we established higher values after a rainier spring-summer period. There is a conspicuous difference between the falling number of extensive and intensive varieties and the year had significant effect on the formation of values. We established with correlation analysis that both the precipitation of vegetation period and the maturing rainfall had considerable effect on the value of falling number. Examining the effect of fertilization on the formation of wet gluten content as a quadratic equation, we found that precipitation may both increase and maximalize the value of this quality parameter. -
Effect of weather conditions on the protein content and baking value of winter wheat flour
83-94Views:146We searched for connections between weather conditions (with its sub-parameters as precipitation and average temperature) and the yearly formation of two quality parameters (protein content and baking value) on three levels of mineral fertilization, based on the results of a variety comparison experiment on chernozem soil, to select those weather parameters and critical periods which have significant effects on the quality of winter wheat flour.
We established that the protein content of winter wheat flour can be increased with increasing levels of mineral fertilizers. Protein content is lower and has higher deviation during non-fertilized conditions in different cropping years than on higher fertilization levels. Thus, it seems proved again that quality (as protein content) is mainly formed by the crop year, but can be improved with adequate agricultural engineering (with mineral fertilization in the present case). The higher sum of precipitation in May, and the lower average temperature after flowering, have the highest increasing effect on the protein content of flour of the examined parameters. Based on the results of the examined period, the rainier and warmer term than average before flowering and lower – average amount of precipitation and colder circumstances are favourable for higher baking values. The analysis with data of decades, proves the importance of the first half of May and the middle of June as especially important periods for quality formation. An increasing nutrient supply has different effects on the varieties; mineral fertilization increased the baking value of GK Öthalom winter wheat variety in almost every case, but the second level of fertilization decreased it in half of the examined years. Additionally, mineral fertilization played a role in the stabilization of the quality of highlighted varieties. -
The relationship between gluten proteins and baking quality
117-122Views:254Wheat, one of the most important cereals, is grown on the largest area in Hungary. During hydration of storage proteins of wheat – gliadin and glutenin – the gluten complex is evolved. The gliadin is responsible for the extensibility of gluten complex as well as the glutenin for the strength of gluten. The structure, composition and rheological properties of gluten proteins influence significantly the baking quality. The gliadin/glutenin ratio and the quality and structure of glutenin fraction play the most important role in evolving gluten complex. Changes in the steps of breadmaking technology also have effect on the quality of product. Several tests proved that the higher glutenin content increases the strength of dough while the higher gliadin content increases the extensibility of dough and decreases maximum resistance to extension. The monomer gliadins play a great part in plasticity of glutenin polymer. The quality of glutenin fraction significantly influences the evolving gluten complex, because of the spiral structure of glutenin which deforms under stress conditions, then the β-spiral structure resumes their original conformation by releasing from stress.
The final quality of product evolves as a result of complex characteristics of wheat proteins, so detailed knowledge on the roles of different protein compounds is the base of the quality oriented product development.