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Analysis methods of quality and traceability for honey
25-32Views:138Honey is our essential food since ancient times. Thanks to the excellent dietetic and medical features, it has an important function in our nourishment. In Hungary about 25.000 tons of honey are produced each year. Most of the produce, about 80% is exported to different countries of the world. Hungarian types of honey have excellent quality. Through exporting, the prestige and demand of Hungarian honey can be increased. In recent years the adulteration of honey caused many damages to producers and traders. The adulteration of honey is not easy to prove. Thereinafter, we represent several methods, such as oligosaccharide analysis or 13C/12C isotopic ratio analysis, which can identify the artificial substances of honey (for example: corn syrup, high fructose corn syrup) or can help to determine the ratio by which original honey can be identified.
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Application of the SDS-PAGE method for the characterisation of winter wheat flour quality
112-118Views:101The 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. -
Antioxidant activity and total flavonoid content of honeys
25-28Views:109The influence of honey on human health has been known since ancient times. Different components, like vitamins, amino-acids, enzymes, and the so called antioxidant activity of the honey play role in this effect, and also in the excellent quality. The aim of present study was to determine the total antioxidant activity and the flavonoid content of some honey samples. These two parameters are widely studied, and a lot of data can be used to compare and analyse. On the basis of them we can state that our results are quite similar than those we can find in literature. Characteristic feature of the examined honey samples is, that the antioxidant activity increased with the darkening of the colour. The lowest antioxidant activity and flavonoid content was produced by the acacia honeys with greenish shade of colour. The highest values was found in the very dark honeys (forest, sage, golden rod). The only exception was the coriander honey, where despite of its lighter colour, very high antioxidant activity was
measured. -
The effect of climatic change on the rheological properties of winter wheat doughs
96-100Views:77In 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 -
The effect of different fertilizer treatments on the sulphur and protein content of wheat
73-76Views:111In this study the effect of N,P and K nutrients on the S and protein content of wheat grains was investigated in a long-term fertilization experiment set up in Nagyhörcsök. The calcareous chernozem soil having the following characteristics: pH (KCl): 7.3, CaCO3: 4.27%, humus: 3.45%, Al-soluble P2O5 and K2O: 60–80 and 180–200, KCl- Mg: 150–180, KCl+EDTA-soluble Mn-, Cu- and Zn-content: 80–150, 2–3 and 1–2 mg kg-1. The experiment had a split-split-plot design with 40 treatments in 4 replications. Plant samples were collected from 2002 and 2004. 2002 was a drought year while 2004 was very wet.
The main conclusions are as follows:
– The sulphur and protein content were than the control higher in every NPK treatments.
– The sulphur and protein content of the wheat grains were higher in 2004 that had a lot of rain than in 2002 that had drouht. -
The Role of Cultivation Systems in Quality Sugar Beet Production
134-138Views:87Producing sugar beet, as it is a demanding field crop, has contributed to the raising standard of plant production. It has an outstanding place among the plants that are cultivated in the intensive plant production system. Rentability of sugar manufacture is determined by the stability of yield and the quality (saccharose content) of sugar beet. In this way, the fundamental interest both of the producers and the processing industry is high yield and quality, year by year. The yield and the quality of the sugar beet are mainly determined by the plant production system, so we studied the effect of fertilization, irrigation and plant protection.
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Comparison of quality parameters of producers' and commercial honeys
31-39Views:154Honey is our essential food since ancient times. In Hungary about 25 000 tons of honey are produced each year, and most of the product (80%) is exported. Hungarian honeys have excellent quality but because of scandals of honey adulteration the interest and recognition may decrease. Therefore we must elaborate a method with which the establishment of adulteration is simple and cheap. In this study we concentrate on simple quality parameters which inspection is not elaborate. These parameters for example sugar- and moisture contains, proline content, electrical
conductivity, element content, pH, HMF content, degree of acidity. We examined these parameters in producers’ and commercial samples. We succeed fund parameters which characteristic of one type of honey thus we have possibility identify of honey type. For example the proline content was very low in the producers’ linden honey (mean 126 mg/kg). This value is lower than the regulation, but in case of commercial linden honey this parameter is higher than regulation. According to electrical conductivity and Potassium content is provable the type of linden honey. -
Qualitative detection of genetically modified organisms in plant samples
309-313Views:93We 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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Optimization of inductively coupled plasma mass spectrometer parameter’s to measuring arsenic and selenium
59-64Views:159In 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. -
Results of a Fertilization Experiment Performed with Sulphur on Rape Seed Plants
116-119Views:109The sulphur fertilizing experiment was introduced in the cropping year of 2001/2002, with winter rapeseed. The experiment was performed on a farm in Magyarhomorog, Hajdú-Bihar County. By selecting the location for the experiment, we had to consider the effect of the hard winter that was very unfavourable for rapeseed production, as there was serious frost damage on the sown area previously used for the experiment. In the arable land experiment, results of three different doses of treatment were compared in two replicates, on meadow soil. FitoHorm 32 S solution was used as a sulphur fertilizer, in doses of 3, 6 and 10 l/ha. Evaluating the results, we tried to find a correlation between the amount of fertilizer and the amount of seed-crop or the oil content of the seed. The nitrogen and sulphur contents of the samples were determined using classical methods and an Elementar VarioMax analyser. By this way, it was possible to examine not only the role of Sulphur in rapeseed production, but also to compare and evaluate results obtained by Kjeldahl and the modern, environmentally-friendly combustion method.
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Use of extensigraph in the examination of wheat flours
17-23Views:119The extensograph is widely used in quality control and research laboratories studying wheat flour quality. The most commonly used measurements include Rm, the maximum resistance (maximum height of the curve); R5 the resistance at a constant extension of 5 cm; E, extensibility (total curve length); Rm/E, the ratio of maximum resistance to extension; and A, the area under curve. The extensograph has proved useful in the classification and assessment of flours on the physical dough properties. Another important application is its use in wheat breeding programs. Furthermore, extensograph is an excellent tool to study the effects of a wide range of ingredients on dough properties of wheat flour (like oxidants, enzymes, salt and additives), and it can also be used measure the changes during the frozen storage. In the present study we provide a review of the scientific literature concerning the possible applications of the extensograph.
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Selenium-speciation experiments from soil samples by accept of ionchromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS) method
106-111Views:129In 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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Effects of cultivar and fertilization on extensograph parameters of winter wheat flours
19-24Views:95In present paper we have examined the effect of mineral fertilization on the extensograph characteristics of wheat-flours. The baking quality of winter wheat is largely determined by cultivar, but it can be influenced by fertilization. Flours were from 4 cultivars grown at six nitrogen fertilizer. The average flour protein content of cultivars was very different (11.8, 13.0, 14.3, and 13.07%, respectively). We have found that the extensograph
properties of dough are affected by mineral fertilization, nevertheless, different cultivars distinctly react to the increase of fertilizer doses. We estimates the correlation between flour protein content and extensograph properties, based on our investigations, it became obvious that the correlation between flour protein content and extensograph parameters is really strong. -
A tárolási feltételek hatása a kukorica Fusarium fertőzöttségére és toxin szennyezettségére
28-32Views:195Corn 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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Following-up organic pollutants in the course of producing foods
244-248Views:96We 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.