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Comparison of alveohraph and extensigraph properties of winter wheat samples
27-30Views:132The rheological properties of dough are determined by the amount and proportion of gliadin and glutenin proteins. Extensibility and resistance to the extension of doughs which can be measured using the extensigraph or alveograph allow good assesment of the baking behavior under realistic conditions. In our study, we compared the extensigraph and alveograph parameters of 87 flour samples. The results showed that the alveograph parameters were different from the extensigraph parameters. The classification of wheat varieties was different, and the order of varieties, as well. The alveograph properties were affected by other factors than the extensigraph properties, except the W value. The two rheological tests did not give similar results, therefor neither test are replaceable.
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Molecular Biological Approach of Crocus sativus L. and its Allies
112-115Views:159The hay saffron (Crocus sativus L.) is a sterile triploid plant, known in human culture only, with no fertile seeds produced. The origin of saffron is still a mist, however it is assumed to be an autopoliploid mutant or a hybrid. The recent classification and most of the former taxonomic publications define C. sativus to be derived from C. cartwrightianus, a wild species. Because of the sterility of hay saffron it seemed to be reasonable to apply molecular biological methods to complete classical taxonomic studies in examining its relations. The DNA polymorphism based AFLP method has confirmed the close relationship between these species.
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Application of the SDS-PAGE method for the characterisation of winter wheat flour quality
112-118Views:126The principle, development and importance of the SDS-PAGE method are presented in this article. The SDS-PAGE method has become one of the basic methods of molecular biological research, because it is widely applicable and its sensitivity is excellent in the separation of wheat storage proteins.
We have shown the application of this method with a concrete example. It was also tested whether, it was possible to obtain a better baking quality product from a large amount of poor quality less valuable wheat by fractioning the flour according to particle sizes after grinding. We studied the rheological properties of flours with different particle size fractions from the original flour. The baking quality of the original flour was B2. The 125-90 and 90-63 μm fractions have significantly better baking quality (B1) than the original flour. The protein contents of these flour fractions were also significantly higher than the protein content of the original flour. We had a question: what has influenced the baking quality: the protein content or other factors? We searched for an explanation on these results in the protein composition of the flour samples. We studied the distribution of glutenin-fractions by SDS-PAGE method and evaluated them. We found with correlation analysis that the amount of LMW-Glutenin D-group (52-60 kDa) is in a strong, negative correlation to the baking quality (r = – 0.855*). Therefore, the baking quality of flour samples was influenced by this glutenin fraction. -
Parameter optimization of an inductively coupled plasma mass spectrometer for measuring arsenic and selenium
81-85Views:173In the last decades, an increased interest has evolved in arsenic and selenium. The aim is to understand the environmental, agricultural and biological roles of these elements. In the case of arsenic, the major reasons are the relatively high concentration of arsenic in marine biota (mg kg-1) and the arsenic contaminated drinking water bases of some Asian countries, as well as Hungary. The toxicity of higher level selenium content is also known; nevertheless, selenium is essential for several biological functions. Considering its essentialness, in our country, the insufficient selenium intake rate causes a lack of selenium. Measuring the concentrations of these elements provides crucial, but unsatisfactory information, as the speciation, i.e. the form of an element presented in a sample is also required.
In both cases, the most suitable method to determine concentration is inductively coupled plasma mass spectrometry (ICP-MS). Our objective was to optimize the variable parameters of the ICP-MS to attain the lowest (the best) detection limit. For this purpose, we investigated the effect of parameter change on net signal intensity and relative signal intensity. With the optimized parameter settings, the limits of detection for arsenic and selenium were determined, which are 0,032 ng dm-3 for arsenic, and 0,097 ng dm-3 for selenium. -
Food safety of plant origin food
161-164Views:178Expectation regarding changes related to food production, transportation, distribution and marketing have changed considerably in several regions of the world over the past decades. It is especially true for highly industrialized countries where not only the food security is important but the food safety is essential too. The concentration of production – processing – distribution involves the danger on the one hand products of unsuitable quality from point of view of nutritional physiology and the other hand ones that may contain substances harmful to human health will become widespread among consumers. We investigated the heavy metal, pesticide remains and mycotoxin content of different plant products.
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Application of the Collision Cell (CCT) in the ICP-MS Analytical System
120-125Views:183Our 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.
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Study of effects on quality of different wheat flour fraction
123-129Views:123Wheat is one of the most important cereals in the world and the bread made of its flour belongs to the everyday life of human mankind.
The Hungarian standard relating to the laboratory production of wheat flour (MSZ 6367/9-1989) does not mention the type of laboratory mill used for milling, and it only builds up some general criteria, such as: the laboratory mill should be provided with four differently nicked barrels, a sieve with appropriate hole sizes, and also with the separated collections of the pilot flour and the bran. Our study was started at this point and the answers for the following questions were aimed to be found: do the flour patterns studied and produced with different grinding and sieving
techniques, widely used in laboratory mills of the same wheat pattern show any alterations after the impact of the formula production as regards chemical constitutions and reologic parameters. Various flours and whole grains of the wheat patterns sieved with different particle sizes were studied in this experiment. In producing this pattern two different mill types of FQC 109 and CHOPIN CD 1 as well as two different grinder types such as PERTEN 3100 and type of RETSCH 200 were applied. There were 3 different corn sizes of 160; 250; 800 μms used in the partition of the fractions. To study the differences the following measurements were conducted: dry matter, ash, protein content, wet gluten content, gluten index, gluten expansiveness, farinographic value, falling number and amilographic rate.
The results this research confirm that the quality of wheat flour can be modified by different methods of pattern production. In all cases the differences can be explained by the flour-bran ratio, and in some of the cases the higher germ content of the fractions also played a role. The results show differences between the various types of mills and grinders, too. -
Investigations on Mud on Heavy Metal Contaminated Flood-Plain of Tisza
96-101Views:123At the beginning of the year 2000 subsequently to a mine accident high heavy metal content mud entered the catchment area of the Tisza and was transported through the whole Hungarian section of the river. The majority of the heavy metals had been bounded to the floating sediment that was deposited on the flood-plain soil during flood forming a new, 5-10 cm thick layer. In the mud samples collected after the flood there was a clearly visible dark grey layer with significantly higher heavy metal content that was formed by the pollution wave and it was sorruonded by a light layer. The upper layer of flood-plain soils are formed from this mud layer during the soil development process, so the amount of Lakanen-Erviö soluble heavy metals that correlate with bioavailable heavy metal content was examined as well. In this case only the lead content was significantly higher in the dark layer.
New mud samples were collected after the 2001 flood. Separate layers could not have been identified, their colour was similar to those of the previous year’s light layers’. Comparing to this light layer the total Zn and Lakanen-Erivö soluble metal content was significantly lower in the mud samples of the year 2001. While the proportions of total and Lakanen-Erviö soluble metal concentrations were equal in both of the layers regarding the elements, these ratios have significantly changed next year regarding Pb and Zn: the amount of Lakanen-Erviö soluble metals considerably decreased.
As a result of sequential extraction the heavy metal content was rather low in the water soluble and exchangeable and NaOH-soluble fractions, so heavy metals found in the mud could be released in greater amount only in case of a heavy acidification. -
Optimization of inductively coupled plasma mass spectrometer parameter’s to measuring arsenic and selenium
59-64Views:211In 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. -
The effect of climatic change on the rheological properties of winter wheat doughs
96-100Views:113In present paper we have examined the effect of climatic change on the extensigraph characteristics of wheat-flours. The baking quality
of winter wheat is largely determined by cultivar, but it can be influenced by weather conditions during growing period. Flours were from 5
cultivars grown at one location in three cropping years. We have found that the extensigraph properties of dough are affected by the weather
conditions, nevertheless, different cultivars distinctly react to the increase of temperature and decrease of precipitation. In generally, the
higher average day temperature and lower precipitation level is favourable to produce winter wheat flour with better quality -
A tárolási feltételek hatása a kukorica Fusarium fertőzöttségére és toxin szennyezettségére
28-32Views:230Corn 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:137We 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:125The 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:179In 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:140Nowadays, 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.