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Access to sufficient water and food of suitable quality is a prime requirement for the improvement and maintenance of public health. Waterborne diseases are typically caused by enteric pathogens which belong to the group of organisms transmitted by the faecal-oral route. In the course of our work, in order to determine the presence of allochthonous microorganisms water of dug wells and springs were microbiologically analysed. The selected nonbottled mineral and well-waters are widely consumed by local people. The survival of faecal coliforms was studied in selected water samples during storage at 4 °C and after desinfection with chloramine and iodine. The microbiological quality of the majority of the analysed well and spring waters is not acceptable. The faecal Escherichia coli was still present in the water samples after 8 and 10 days and presented higher resistance to chloramine, but not to iodine, than the Escherichia coli EC/2 strain chosen for comparison.

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Acta Alimentaria
Authors: Sz. Szélpál, Zs. Kohány, E. Fogarassy, I. Galambos, A. Koris, J. Csanádi, Gy. Vatai and C. Hodúr

The largest quantities of by-products of dairy processing originates from the cheese making. Whey proteins are used for animal feeding and human nutrition as well, for example in dry soups, infant formulas, and supplements. The fat components of the whey might impair its use. The aim of our experiments was to investigate the separation of the lipid fraction of whey. The microfiltration is said to be a gentle and energy efficient method for this task. During the measurements 0.2 μm microfiltration membranes were used and the membrane separation was enhanced by vibration, inserting static mixer and air sparging. The de-fatting efficiency, the retention of the whey components, the flux values, and the resistances in different combinations were compared in this paper.

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We have investigated the Total Glycoalcaloid (TGA), nitrite, and nitrate contents of some Hungarian and foreign potato cultivars in relation to the effect of different combination of fertilisers and green manure, late blight management strategies (none, programmed, or prediction based spraying), and irrigation regime for three years. The Hungarian cultivars have exotic potato species like S. acaule, S. demissum, S. stoloniferum, S. vernei, or S. tub. ssp. andigenum in their genetic background as sources of resistance genes. No effect of fertilisers or irrigation was found on the level of glycoalkaloids and nitrate contents, which were influenced mostly by the genotype and season. In conclusion, the absolute amount and the presence of different antinutritive components of potato tubers were influenced by the technology, genotype, and season in a complex manner. These results in general prove that ware potato production utilising intensive commercial agrotechnical practices and common cultivars is safe regarding the nitrate and TGA content of tubers.

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Acta Alimentaria
Authors: E. Tománková, J. Balík, I. Soural, P. Bednář and B. Papoušková

This study presents findings from comparing the properties of anthocyanin pigments: i. malvidin-3-glucoside (Mal-3-G), the most significant anthocyanin present in young red wine; ii. Vitisin A (5-carboxypyranomalvidin-3-glucoside), a major product from a reaction induced in red wine between Mal-3-G and pyruvic acid during its ageing. These pigments were determined and compared to the absorption spectrum in 200–770 nm at various pH values, such results including the ability of cation Al3+ to change the values of absorbance. Changes in the colour parameters L* a* b* were determined in the CIELAB colour space of Mal-3-G and Vitisin A in relation to pH and the addition of AlCl3. Both coloured compounds were investigated for their resistance to discoloration by sulphur dioxide. Total antioxidant activity was evaluated by two methods (FRAP, DPPH), and the values were compared to other phenols.

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Acta Alimentaria
Authors: T. Gelencsér, R. Juhász, M. Hódsági, Sz. Gergely and A. Salgó

Resistant starches (RS) can be used in the food industry aiming to enhance the dietary fibre content and reduce the glycaemic response of food. The aim of the present study was to investigate the physical and chemical properties of different resistant starches (origin, type of resistance) and their comparison with native starches in pure form and in stoichiometric mixtures. Measurements were carried out to determine enzymatic digestibility, water absorption, thermogravimetric parameters (DSC), and viscometric characteristics (RVA) of resistant and native starches and their mixtures. Enzymatic digestibility and water absorption were reduced linearly by adding resistant starches into the mixtures. RVA parameters have shown non-proportional character in the stoichiometric mixtures. The results of DSC measurements proved that the gelatinisation of resistant starches is quite different and only chemically modified resistant starch was heat-sensitive. Results indicated that circumspect evaluation is needed in the selection of resistant starch products for the development and innovation of food products with reduced glycaemic response.

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The authors have developed transgenic wheat lines with broad range of herbicide resistance. The transgenic wheat, containing bacterial derived alien gene (bar) regulated under the maize ubiquitin promoter, is resistant to glyphosinate (phosphinotrichin) agent family. The presence of bar gene expression product (phosphinotrichin acetyl transpherase enzyme, PAT) was confirmed by PAT-specific ELISA (Enzyme Linked Immuno Sorbent Assay). The qualitative and quantitative chemical composition of the transgenic wheat lines in comparison with their non-transgenic counterpart (year 2000-2002) and protein utilization of the wheat wholemeal flours (year 2002) were summarized. Nutritional evaluation of the protein was based on a rat model by using N-balance experiments. Among the protein sources, heat-treated samples were also introduced into the experimental diets. It was found that heat denaturation of the proteins led to results with somewhat increased biological value indices. The introduction of GM technology did not affect food intake or nutritional performance of the rats.

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Creating typology is a comparative method to investigate the physical or other characteristics of the built environment. It can be a useful instrument to facilitate the thermal performance assessment of existing buildings. Heat material’s resistance and construction techniques play a significant role in energy performance of buildings. It is influenced by many factors, such as ambient weather conditions, building structure, and heating, ventilation and airconditioning systems.

The study was focused on analyzing five types of residential buildings at the center of the Sulaimani city (north of Iraq) to assess the energy performance of the building types and comparing results with dynamic analyses, using IDA ICE 4.7.1 software. The results revealed that the thermal performance of the buildings is mostly influenced by the variations in the construction techniques and materials.

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Single row pile groups are gaining popularity as foundation system for both buildings and bridges. They are a reasonable and economical solutions for structures with low vertical loads e.g. bridge abutments. The lateral resistance of a pile group is the result of contact pressure between the individual pile shafts and the soil. When designing this kind of structure, the estimation of displacements and bending moments is the main focus of the calculation. In most cases single piles are modeled by assuming a Winkler material. For their calculations, designers typically employ one of the commonly-used structural FEM codes (e.g. AxisVM, Fem-Design). On the other hand, advanced, truly 3D FEM packages (like MIDAS GTS, Plaxis 3D) are available, allowing for realistic modeling of the soil environment and soil-structure interaction. As an intermediate solution, packages based on traditional approaches are also available (GEO5, CGU). In this paper, results obtained using three different calculation methods and packages are compared.

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The paper summarizes the results of experimental and numerical investigations, carried out at the CEMSIG Research Center ( http://cemsig.ct.upt.ro ) of ‘Politehnica’ University of Timisoara, on compression members of pallet racks. Members of two different cross-sections, with and without perforations, have been tested on the aim to calibrate a design approach to evaluate their ultimate strength and, on this basis, to check the buckling resistance of bar members accounting for distortional-global interaction. The lengths of upright specimens and testing procedure, for local and distortional buckling, were chosen according to European pallet rack design code provisions. Test on base materials and imperfection measurements have been also performed. In order to study the distortional-global interactive buckling, the ECBL method has been used. The paper presents the main results of these investigations.

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Permanent deformation in the form of rutting is the most frequently occurring defect of asphalt pavements. This paper gives a short overview of bitumen performance parameters used for characterization of resistance against permanent deformation in the USA and Europe. Investigation of relationships between rheological parameters measured with dynamic shear rheometer using different test modes is presented. The test program consisted of measuring of performance parameters of paving grade, hard, polymer modified and rubber bitumen binders. They were tested in the linear viscoelastic range and beyond. Correlations between complex shear modulus, combined with phase angle, complex viscosity, stress sensitivity, and zero-shear viscosity are given. However, the correspondence of binder parameters with relevant performance parameters of asphalt mixes have to be further investigated.

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