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  • The effect of soil cultivation systems on organic matter distribution in different grain size fractions of the soil based on three years of experience
    22-30
    Views:
    71

    Changes in the physical distribution (particle size and the state stability against decomposition) of the organic carbon pool in tilled layers of Hungarian field soil under different tillage treatments were studied. Three years after starting the experiment, soil samples were fractionated (they were taken in March 2005) by their particle size and density. The treatments caused well measurable, significant effects on two fractions of intra-microaggregate organic matter (53-250μm particle-sized, well and less decomposition-resistant pools) and onto their relative rate in the organic carbon pool of the whole soil.
    Different tillage treatments caused different distributions in the organic matter fractions. In regularly intensely cultivated soils evolve different physical structure, particle size-distribution, which reduce the soil fertility and its resistance against outer impacts.

  • The influence of fraction size on the chemical composition of winter wheat flour
    123-126
    Views:
    83

    Wheat 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 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. Various flours of the wheat pattern sieved with different particle sizes were studied in this experiment. 
    In producing this pattern we used FQC109 type of mill. There were 5 different corn sizes of 250-200; 200-160; 160-125; 125-100; <100 μms used in the partition of the fractions. The results this research confirm that the quality of wheat flour can be modified by different methods of pattern production.

  • Study of effects on quality of different wheat flour fraction
    123-129
    Views:
    95

    Wheat 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. 

  • Application of the SDS-PAGE method for the characterisation of winter wheat flour quality
    112-118
    Views:
    99

    The 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.

  • Examination of different grain hardness varieties of the grinding technology properties of wheat
    423-435
    Views:
    171

    In the mill industry, the purpose of the grinding technology is to separate wheat endospermium and shell and to recover grists. The most important and the highest energy requirement operation is shredding. Flour quantity and quality produced from wheat depends on the variety of wheat that will be shredded, the type of grinding equipment and the condition used before the grinding. For this reason, during my experiments, I ground two grain structured varieties of wheat in laboratory conditions using a disk grinder, stone grinder and roll grinder in air-dry and conditioned states. We measured the equipment’s performance and the produced grist’s particle size distribution, followed by the calculation of the energy requirements of the grinders. In the grinding experiments we compared the ash contents of the different particle sized grist’s fractions to map the wheat’s particular properties.

  • Movement of Particles in the Air
    22-26
    Views:
    98

    The physical characteristics of particles (seeds and fertilisers) can strongly influence their movements both in seeding and spreading machines and in the air. It is therefore essential to study these particles when constructing such machines. In this respect the size, shape, coefficient of friction and aerodynamic resistance of particles are of great importance.
    Due to their irregular shape, determining the size of particles is a troublesome process. A precise description of particles has to include several sizes and can be obtained from their screen size. Many physical properties of particles are relevant during movement in the air, but the aerodynamic resistance coefficient is the most important (Hofstee et al., 1990). Two types of wheat and four types of fertiliser particles were investigated (supported by the National Scientific Foundation OTKA, T-026482). An elutriator was designed and constructed (Csizmazia et al., 2000), in which an airflow is supplied by a centrifugal fan. Air velocity was measured with a thermal sensor. Particle sizes, mass and terminal air velocity were measured. The influence of the aerodynamic resistance coefficient on the particles’ motion is also discussed.

  • The aggregate stability of the soil in respect to the uniform aggregate stability indicator
    83-99
    Views:
    84

    Soil structure and its quality are fundamental properties because they control many processes in soils. Tillage, crop and other factors influence soil structure. Efficient protection of it needs indication of changes in soil structure. A new Normalized Stability Index proposed by Six et al. (2000) tries to evaluate these changes, which was compared with some former used indices. The most common method (wet sieving) was modified to reduce the confounding effects of different particle size distribution of different soil types and method used to the investigation. Changes in soil structure caused by tillage and crop management therefore have been made quantitative and comparable. In this paper, we review the new method and Normalized Stability Index proposed by Six et al. (2000) and present the results of our investigations.