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The composition of gluten proteins and their effect on the rheological properties of gluten
124-129Views:193Wheat is the major cereal component of bread in the world and is grown worldwide. Of the cereals only the bread wheats – and less the triticale – includes storage proteins that play an important role in the performance of gluten. Proteins of gluten complex may be present in two classes:
− low molecular weight (gliadin-) components, and
− high molecular weight (glutenin-) components.
Gliadins shown appreciable heterogenity and can be separated into 40-50 components with gel electrophoresis. The composition of gliadins is employable for the identification the wheat varieties and to investigate the varieties. In the decreasing electrophoretic mobility sequence may be distinguish α-, β-, γ- and ω-gliadins. A glutenin subunits may be include in two classes:
− high molecular weight glutenin subunits (HMW-GS),
− low molecular weight glutenin subunits (LMW-GS).
Wheat varieties can be identified by glutenin and their quality selection is also possible. The gliadin’s polypeptides encoding genes are located on the short arm of chromosomes 1A, 1B and 1D, 6A, 6B and 6D. Genetic coding for HMW subunits is located on the long arms of chromosomes 1A, 1B and 1D, the LMW-GS are also located on chromosomes 1A, 1B and 1D (Glu-3 loci) near the gliadin-coding loci.
Storage proteins affect the rheological properties of gluten by two factors:
1. The quality and quantity of the protein components of the gluten complex,
2. The interactions between the protein fractions. -
New possibilities to determine wheat quality parameters by near-infrared spectroscopy
65-69Views:178Analyses and methods in wheat quality determination require more sample, time, work and cost, thatswhy flour quality control needs rapid, reliable tools. Near-infrared spectroscopy has many advantages, which make it suitable in quality control. NIR instruments need calibrations to their work. In our study we examined gluten content, falling number, valorigrpahic waterabsorption, alveographic P/L and W value of wheat samples. Modified partial least squares analyses on NIR spectra were developed for each property. The results show that we got such calibration modells, which are able to predict the properties (expect falling number) with enough accuracy.
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Quality management and traceability in crop production
273-277Views:173Today, food safety and quality is an everyday issue. Scandals in the food industry drew attention to the role and responsibility of food producers in the food chain. The European Union has set up a new integrated approach towards food safety, to which Hungary as an EU member and export-oriented country has also joined. The new “from farm to fork” principle states that food and feed production cannot be handled separately, as only feed produced from good quality raw materials can ensure safe food products. Another important issue is the traceability of products, allowing for the localization and recall of the defected item. In Hungary, there have been different documentation systems for tracking and tracing products, such as the land register in crop production, animal register in the livestock sector and hygiene registers in the food industry. In order to meet EU requirements, there is a growing number of initiatives to include primary production in the scope of food safety standards. The study introduces and compares the various management systems used in crop production.
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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. -
Element Content of Herbaceous Plants in the Floodplain Meadows
55-58Views:132Animals require well-balanced nutrition. The elemental content of the vegetation of meadows is influenced by as many factors such as heat, rainfall, irrigation, soil type and nutrients, meadow types, species, aspects of the vegetation period and cultivation.
Natural meadows used extensively are common sights on river floodplains. Since chemicals are banned and the species number is high, measuring the elemental composition of plants on these meadows is beneficial. Cenological survey and element content measurements were held on the rich flora of four natural meadows in the year 2001.
Weeds, in a wider sense, are plants not directly involved in growing, although their nutritional values make them important costituents of feed. Meadows are enriched by their relatively high microelement content.
On the sampling sites, the ratio deviated from the ideal 2/3 parts monocotyledon and 1/3 part dicotyledon, but this did not mean a Mn deficiency as it would have been assumed. -
Studying of quality parameters of Hungarian and Greek honey samples
147-153Views:255Honey 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.
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Comparison of macroelement and microelement contents of conventionally and organically grown crops
87-92Views:184Nowedays one of the most important issues to discuss is the healthy nutrition: feeding our bodies with high quality nutrients, which is free of chemical residues. The demand for healthy and nutritious food is increasing worldwide, that results in the growing popularity of consumption of organic food. Several studies dealing with the nutrient content of traditional and organic food have been published lately, since it became clear that eating food contaminated with chemical residues damage to health, food and the environment. Therefore it would be desirable to find out if organic food is really superior to conventional one. In our study we analyzed the dry matter, ash, macroelement and trace element content of organically and conventionally grown crops (carrot root, potato tuber and parsnip). Our results provide further information to consumers about the nutritional value of organic and conventional crops.
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Investigation of the Quality of Winter Wheat in a Sulphur Fertilisation Experiment, 2001/2002
153-156Views:150We have started a small parcell and a factorial S fertilization experiment with winter wheat in the 2001/2002 cropping year to examine its effect on yield and quality. The scene of experiment was the Latokep Experimental Station of the DE ATC (calcareous chernozeem) in case of small parcell examination and the Agricultural Company of Felsőzsolca (brown forest soil) in case od factorial examination.
The protein and gluten content of the grain was investigated with PerCon Inframatic 9001 NIR Analyser, then we have measured these parameters with PerCon 8620 infra appliance. After the milling we measured the following parameters: glutenindex, farinographic parameters (farinographic index, water absorption capacity, dough development time, stability, softening, extension) and valorigraphic index.
Based on the results there’s no justified relation between the fertilization and the protein and gluten content. The valorigraphic index of the samples taken from Felsőzsolca factory characteristically increased as a result of the S-fertilization. In the small-parcell experiment the values of the water absorption capacity, the dough development time and the softening parameters from the valorigrphic parameters depended significantly from the mineral treatments. Signifikant quality improvement wasn’t experieced.
There was sampling in all of critical phenophase (…). The green plant samples were examined on element content with ICP-OES. These measurements are currently in progress. -
Influence of Foliar Treatments on the yield and quality of Sugar Beet
119-123Views: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 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 -
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. -
Research on rheological characteristics of winter wheat varieties
266-272Views:188The gluten examination test is dominant in Hungary, comparing it to the qualification system of other countries. The determination of alveographic parameters is a basic criterion of winter wheat specifications in some western and southern European countries.
In the Hungarian and foreign winter wheat qualification systems, in the standards, there is no limit for extensographical parameters. Customers dictate the limits and make their claims as to the specifications.
We analyzed the alveographic and extensographical parameters of 19 winter wheat varieties grown by the Cereal Research Non-Profit Company in Hungary, and we made a comparison between the results in the challenges of the European Union expectations.
Examining the information of alveographic and extensographical values, we found that the experimental varieties provide high base to flour types suitable for baking bread and baker’s ware. The GK Élet, GK Petur, GK Memento, GK Csillag, GK Kapos and GK Marcel varieties can meet the market of paste flour needs, too.
In the variety series, the GK Kalász represents the highest values and the GK Garaboly shows the lowest parameters regarding the alveographic W and the resistance to extension.
On the basis of relation, we can establish that we can estimate the following little known and used quality indexes: the extensographical resistance to extension with extensographical energy and the alveographic W value, the extensographical energy with the alveographic W value and the alveographic P and L values with the other alveographic parameters. -
Quality analysis of the near-infrared spectra of wheat samples
97-100Views:151The near infrared spectroscopy is widely used in the different industries as a rapid, non-invasive analitical tool. It is suitable for identification, qualification and quantitative analysis as well. As this technique is indirect, to make accurate calibration equations we need a proper sample population. Before the quantitaive analysis, developing calibiration modells we have to collect and examine the spectra. In our study we examined wheat samples with known origins to find if there is any effect of the growing area on the NIR spectra.
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The Effect of Grazing Intensities on Magnesium Contents
8-13Views:246Research was carried out on two areas of grassland in Hortobágy National Park, Hungary. Two herds of Hungarian Grey Cattle were kept in free range grazing and the effects of grazing pressure on the magnesium content of soil and ryegrass (Lolium perenne L) were determined.
Changes of plant available and total soil magnesium content under different grazing intensities did not show any evident tendency on the investigated grasslands. Different amounts of cattle faeces, urine and trampling had no effect on the magnesium concentration of ryegrass. We conclude that the magnesium content of ryegrass on both grassland sites as moderate grazing and overgrazing matches the requirements of cattle. Symptoms of magnesium deficiency of cattle will likely not appear. -
Effect of mineral fertilizers with different sulphur content on the yield of winter wheat in a small plot experiment
97-100Views:153We can find more and more references on the importance of sulphur and sulphur fertilization, mainly in the case of most important field crops, as cereals, maize, and the oilseeds. The traditional sulphur sources continuously lost their importance by the stringent air pollution orders and nowadays they are not able to meet the demands of plants. Besides, the application of superphosphate, as phosphorus mineral fertilizer, decreased in several countries. Sulphur fertilization is required in most cases to reach the required yields and quality parameters. The lack of
sulphur causes decreased nitrogen utilization and yield by cereals as winter wheat, moreover, results less favourable baking parameters.
We have examined the N and S content of different parts of winter wheat plants in a small plot experiment at the University of Debrecen, Centre of Agricultural Sciences, Látókép Experimental Station. We have also studied the effect of different sulphur fertilization forms and doses on the baking quality parameters and yield. Our aim was to contribute to the development of yield and quality improving sulphur fertilization methods, adaptable by practice.
We have measured the lowest yield in the case of one of the control plots, and 100 kg/ha nitrogen, 80 kg/ha potassium and 70 kg/ha phosphorus nutrient supply resulted the lowest yield (8.7 kg/plot). The maximum yield, 10.2 kg/plot was also experienced on superphosphate fertilized plot by the application of 140 kg/ha phosphorus dose. Application the first dose of both Biofert and FitoHorm 32 S leaf fertilizers raised the yield from
9.1 to 9.9 kg/plot. ANOVA proved that Biofert and FitoHorm 32 S had no significant effect on the amount of yield, the increase is only a tendency. -
Foliar treatments of Sugar beet
55-59Views:122The 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 and leaf samples at 4 week intervals, starting in August. The quality of root (sucrose, potassium, sodium and alfaamino N content) was determined from filtrated beet broth, by an automatic beet laboratory system, called VENEMA. Leaf samples were measured with ICP-OES.
We found that the crop and the sugar yield were significantly influenced by the foliar treatments. -
Molybdenum - accumulation dynamics of cereals on calcareous chernozem soil
81-85Views:139This work is about the molybdenum-accumulation of cereals analyzing soil and plant samples from a field experiment set in
Nagyhörcsök by Kádár et al. in 1991.
In this long-term field experiment different levels of soil contamination conditions are simulated. Soil and plant samples were collected
from the experiment station to study the behaviour of molybdenum.
In this report results of maize, winter wheat, winter barley and soil analysis are presented. The conclusions are as follows:
– Analysing soil samples from 1991 we have found that roughly half of the molybdenum dose applied is in the form of NH4-acetate+EDTA soluble
– Comparing element content of grain and leaf samples we have experienced that molybdenum accumulation is more considerable in the vegetative plant parts
– Winter wheat accumulated less molybdenum then maize in its vegetative parts. Comparing molybdenum content of winter wheat to winter barley we found that the concentration of the element in wheat was lower by half than in the winter barley. It seemed that molybdenum accumulated to the least degree in winter wheat. -
Investigations on Mud on Heavy Metal Contaminated Flood-Plain of Tisza
96-101Views:136At 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. -
Analysis methods of quality and traceability for honey
25-32Views:208Honey 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:133The 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:173The 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:123In 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:154In 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:131Producing 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:255Honey 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: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.