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Authors: J. Tarek-Tilistyák, J. Agócs, M. Lukács, M. Dobró-Tóth, M. Juhász-Román, Z. Dinya, J. Jekő and E. Máthé

The nutritive value, the microbiological safety of oilseed cake (OSC) obtained from naked pumpkin seed (PuC), sunflower seed (SC), yellow linseed (LC), and walnut (WnC), and their impact on wheat flour (WF) dough and bread sensory characteristics at 5% and 10% addition ratio were investigated. The OSCs had high protein (34–50%), fat (8–15%), total dietary fibre (23–36%) content and high energy value (383–444 kcal/100 g)). The OSC samples with a minimal exception fulfilled the requirements of feed legislation in force. An increased water absorption, dough development time, and reduced elasticity were observed probably due to the enhanced fiber and protein content. Dough stability increased with WnC, and decreased with PuC or SC addition. Enrichment provided the appearance of a brown bread for WnC, of a half-brown bread for LC. PuC gave an unusual look. The appearance of OSC fortified bread similar to daily bread, was an advantage resulting the 1st rank for 10% WnC bread and the 2nd one for 10% LC bread (P=0.05). The studied OSCs are suitable for food enrichment, however, in case of PuC and SC fortified flour blends, hydrocolloid application is recommended. Our data suggest that the newly developed fortified breads could be a valuable source for healthy nutrition.

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The present investigation was undertaken to optimize the level of ingredients (milk fat, sugar, and mango pulp) for functional dairy beverage using Response Surface Methodology. Central Composite Rotatable Design with milk fat (%), sugar (%), and mango pulp (var. Chaunsa, %) as independent variables produced 20 different combinations that were used to investigate the effect on viscosity (cP), antioxidant activity, and overall acceptability. The response surface three dimensional graphs were plotted as a function of two variables to show the effect of level of ingredients on physico-chemical and sensory properties of the beverage. Significant correlation models were established with the coefficient of correlation (R2) greater than 0.8. An optimization of process variables was attempted for maximum antioxidant activity and overall acceptability. ANOVA tables revealed that increase in fat and sugar levels lowered the antioxidant activity, while enhancement of mango pulp significantly increased both antioxidant activity and overall acceptability of the beverage. The optimized levels of ingredients were 0.5% milk fat, 6.0% sugar and 30% mango pulp.

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Authors: M. Tomczyńska-Mleko, W. Gustaw, T. Piersiak, K. Terpiłowski, B. Sołowiej, M. Wesołowska-Trojanowska and S. Mleko

The objective of the research was to obtain aerated gels by magnesium and iron(II) ion induced gelation of preheated whey protein isolate dispersions. Preliminary research allowed finding conditions of the pH, protein, and ion concentrations to produce aerated gels capable of holding air bubbles. A novel method applying gelation and aeration process simultaneously was used. Aeration using a laboratory mixer at 2000 r.p.m. produced stronger aerated gels than using a homogenizer at 8000 r.p.m. The gelation process was monitored using an ultrasound viscometer and a constant increase of dynamic viscosity was noted. A different aerated gel microstructure was observed for magnesium and iron(II) induced gels, which probably resulted in differences in the texture and viscosity, as well. The aeration process decreased hardness. In some cases texture parameters correlated with the viscosity measured using an ultrasound viscometer. Aerated whey protein gels could be applied as matrices for food applications or to controlled release of active ingredients.

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In this paper, a new coarse space based on Chebyshev polynomials is considered as a preconditioning technique for the solution of algebraic systems of equations arising from image reconstruction. These systems are commonly obtained from the use of Compactly-Supported Radial Basis Functions for interpolating scattered image data. Here an efficient and robust coarse space preconditioning technique is presented and the convergence behaviour of the associated iterative method upon different types of functions used for designing the coarse space is studied.

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The paper presents procedures of the slip calculation in steel and concrete composite structures under quasi-long-term load with flexible stud connectors. To describe the slip relation s = s (P), exponential functions are used as appropriate for using in engineering practice. The former already existing expressions for calculating the slip for short-term loads were generalized. The values of factors for the formula were determined on the basis of the experimental investigation.

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The grid and cluster computing uses interconnected nodes to solve a problem in parallel in order to improve the response time of the job. Diffusive load balancing algorithms work well when the nodes in the system have the same processing capacity. However, little attention paid in diffusion load balancing techniques, for the nodes with different processing capabilities. In this paper, a load-balancing algorithm using diffusion technique proposed for distributing the load between the nodes by treating the loads as an integer quantity. The proposed load balancing algorithm distributes apportion of excessive workload of a heavily loaded node to a lightly loaded node by considering the node’s processing capacities.

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The energy demand of the built environment is almost 50% of the total energy demand of a national economy. What solutions can architects offer to reduce environmental and energy problems? One of the most effective methods to develop highly efficient, sustainable building systems is a research program based on energy simulations and monitoring of the building management. The research team, the Author involved in, is on the right way to lay down milestones of an accurate design method to be able to predict and minimize the total energy needs of the building as early as the design phase. Pre- and post-processing energetic and climatic simulations are made during the whole design process. Based on the simulation results continuous alteration can be developed on the planned building complex. The main purpose of this paper is to demonstrate the dynamic simulation and measurement concept of the program in an actual demonstration building of the University of Pécs, which is one of Hungary’s first energy efficient industrial and office buildings with energy-plus potential.

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Thixotropy is the reversible change of the materials rheological properties caused by external mechanical forces. Materials with this behavior can be found at several areas, nevertheless the examination of the phenomenon is rare. Materials like paints, or ketchup can show thixotropic behavior, but in this paper pays attention to geotechnically relevant materials like bentonite or red mud. To understand the reason of the thixotropic behavior measurements were performed. These are shown in this paper (phase analysis and rheometry) to help understanding and comparing the two materials thixotropic behavior.

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Deterioration of concrete materials exposed to an aggressive solution is often characterized by the leaching of calcium and silicon compounds from the cement matrix. This paper presents the results of the study of concrete composites exposed to the various sulphate environments (sulphuric acid and magnesium sulphate solutions) under laboratory model conditions. The leaching of the calcium and silicon from concrete specimens has been studied during 180 days using X-ray fluorescence method for leachate analysis. As expected, sulphuric acid of pH3 was confirmed to have the most significant effect on the studied ions releasing. The released amounts of analysed ions were 192.2 and 9.6 times higher for calcium and silicon ions, respectively in H2SO4 with pH=3 when compared to fresh water. The concentration of released calcium was 2.6 times higher

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Today, at the beginning of the 21st century, the standards of living conditions are defined by the current financial and economic situation. It has impacts on the smallest details of everyday life as well as on residential purchases and constructions also. These are the sectors that mainly felt the lack of funding in the recent years. Although the treatment of this problem should be a simple answer, ecological, economical and social factors generate a more difficult solution. A very important issue in today’s society concerns making the use of the un-preferred living spaces within an existing home. There are many types of these living spaces, including for example out-of-date country buildings that have lost their function, or a variety of apartments in the cities. It became clear that living in prefabricated (panel) buildings is the most undesirable for the population, so the biggest part of the research is about the theoretical rehabilitation of these buildings.

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The aim of the paper is to determine a methodology for calculating the needed airflow rate (including fresh air) in an occupied room, based on carbon dioxide measurement and calculation, in order to maintain the comfort indoor air quality. The calculated airflow rate should optimize the investment and the operating costs of HVAC equipment. In the work there are analyzed the calculation methods used to determine the ventilation airflow rate. It is presented the methodology for calculating the ventilation airflow rate for a room with people inside by using the measured values of carbon dioxide concentration. The connection between carbon dioxide concentration and ventilation airflow rate is verified by experimental measurements. This methodology is applicable in Slovakia because it complies with all current standards. The result obtained by using this calculation method is almost the same with that achieved from experimental measurements. To confirm the results, it is presented a case study of an office with occupants, in which the ventilation airflow rate calculation method is applied.In the article only a part from the total work is presented. The experimental measurements were carried out from 2011 to 2014. Approximately 54 measurements were covering total days or weeks. The following factors have been measured: indoor air temperature, outdoor air temperature, relative humidity of indoor air, relative humidity of outdoor air, concentration of CO2 in indoor air, concentration of CO2 in outdoor air, pressure difference and wind velocity. Ventilation by infiltration was calculated based on these factors using several methodologies. The methodology of measurement is not subject to the article. In this article only one aspect is investigated: CO2 concentration.

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This article is a case study about the investigation of various technologies in a relatively small footprint to achieve a constant reliable quantity and quality of treated water suitable for municipal and boiler feed applications as well, while inlet raw water sources can be very much different causing a wide range of quality fluctuation.

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The importance of alternative office spaces for more productivity and space efficiency has been analyzed: the way of usage as it was common in the past decades and how new technologies and decreasing productivity in the tertiary and quaternary sector urge intervention in the traditional structures and hierarchies to attain top competitiveness. The paper takes the form of a literature review, considering the history and functionality of the work environment and its widening scope to consider how it would be possible to use the existing office buildings more sustainable, healthier by having more productive workplaces at the same time.

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This paper is devoted to efficient computer implementation of coupled salt and moisture transport processes. Three material models are summarized first and then a general form of coupled transport processes is formulated. The system of balance equations is solved numerically with the help of the Galerkin method (in space) and the generalized trapezoidal rule time integration. Implementation of the transport processes into the open source computer program SIFEL is briefly described.

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Authors: Neritan Shkodrani, Costantine Stamatopoulos, Luisa Dhimitri and Ergys Anamali

This paper presents the stability problems of an artificial cohesion-less embankment slope supported on a saturated silty clay layer.In June 2011, an embankment about 9.00 m high started to be constructed in the Energetic Park of Porto Romano, in Durres city, Albania, as part of Preloading to Mitigate Seismic Risk project. The embankment, foreseen to be built in a conic trunk shape form, was to be used as a preload during the consolidation process of the site.Eighteen days after starting the construction process, when the embankment reached the height of 6.35 m, a soil stability failure of the embankment occurred. The calculations include the embankment slope stability analysis, during the design phase, considering the total height of the embankment (9.00 m) and at the moment of failure when the embankment height reached 6.35 m. The paper also presents the results of a back calculation of shear strength parameters at the moment of failure. Probability Based Design Method and Eurocode 7 Design Approaches are used during the analysis, considering long-term (drained) and short-term (undrained) conditions of the silty clay foundation.

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The paper presents a case study that summarizes the monitoring results of a steel bridge strengthening project where a damaged structural element was temporary strengthened with fiber reinforced plastic sheet. The evolution of damage and the effects of strengthening were monitored with a computerized 24-channel displacement measuring system during normal traffic operation. The results of the monitoring project confirmed the efficiency of the proposed strengthening solution by comparing displacement results prior and after the strengthening intervention, and highlighted the need for applying a system that is capable to follow fatigue damage evolution.

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The adsorption properties of natural zeolite (clinoptilolite) has been studied in order to determine its applicability for copper and zinc removal in acid mine drainage treatment process. For purpose of these experiments the determination of the sorption equilibrium and removal efficiencies were performed under batch conditions using single and dual-component solutions. The experiments were carried out under acidic conditions (pH approx. 4). In general, the obtained results from kinetic experiments showed rapid decrease of the metal concentration during the first 10 min, corresponding to ~80% total removal of ions from both single and dualcomponent solutions. This initial rapid period was followed by a further slow drop in metals concentration caused by ion-exchange in deeper structure of zeolite.Preliminary tests on the real samples of acid mine drainage from Smolnik mine, Slovakia, showed that natural zeolite has a potential as an alternative low cost adsorptive material for acid mine drainage treatment.

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Counties of Hungary (with special focus on Zala) were studied based on two different parameters of waste management: the extensiveness of waste collection and the amount of waste per capita. Other indicators were also examined, which may be related to the amount of waste per capita such as GDP per capita or educational level in the area. It was found that the former might have a positive correlation, while the latter indicates only a weak correlation. Based on the conclusions the waste collection is expected to be further improved in Zala County, while probably increasing pressure will appear on waste recovery matter.

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The Slovak building environmental assessment system (BEAS) was developed on the basis of existing systems used in many countries. BEAS as a multi-criteria system which is incorporated in proposed main fields: site selection&project planning; building construction; indoor environment; energy performance; water management and waste management. The goal of waste management is to minimize the waste generated from construction, renovation, and demolition of buildings and to minimize waste generated during the building occupancy. The field of waste management will be introduced in the paper. The aim is also weighting and analysis of significance of waste management indicators using AHP method.

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The contribution deals with collection and recycling of portable battery and accumulators. The present state in Slovakia isn’t suitable. The paper mentions possibilities of its solution by example from neighbouring region. This state is unfavourable as from look position of the state to European legislative and its strike (directive EU2006/66/ES) and producers and importers, who are responsible for performance of engagements.

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This paper is focused on utilization of coal fly ash, steelmaking slag and glass bottle fragment in concrete production. Each of these wastes was mixed into concrete, and compressive strength was tested.The first part of this paper is focused on Portland cement replacement by mechanochemical activated coal fly ash and the second part is aimed to natural aggregate replacement by steelmaking slag and glass bottle fragment in concrete mixture. The results showed that coal fly ash has a positive influence on compressive strength development, and steelmaking slag and glass waste can be successfully used as a natural aggregate replacement.

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The expected effects of the introduction of landfill tax on waste management are hardly predictable. There are many objective reasons for that. Probably the most important one is that the primary aim of the pollution related taxes is to increase the price of the given product or service with internalizing the environmental benefits. Consequently, this is an incentive for altering the consumption patterns, which may contribute to decrease the negative effect on the environment as well. However, waste management is a very special activity as its purchase is compulsory and a waste management fee is levied on users of the service.In our research we are investigating what are the environmental benefits of different waste management systems. What are the costs and incomes in these systems, and how a flat landfill tax will influence these costs and incomes relative to the external benefits.

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Authors: Jani Tomperi, Tuulikki Luoma, Eva Pongrácz and Kauko Leiviskä

Increasing amounts of wastes, seasonal changes and tightened waste legislation and regulations in EU and Finland together with long distances cause challenges to waste management in Lapland. Anaerobic digestion (AD) process produces biogas with high methane content and is one potential waste-to-energy technology to produce heat and electricity in Combined Heat and Power (CHP) plant, reduce harmful landfill gases and requirement of external energy produced by fossil fuels. Local biogas production in anaerobic digestion processes also reduces the waste transportation expenses to landfills, which can be hundreds of kilometers away in Lapland. Efficient waste management and producing renewable energy improve the image of the area. In this study, the amount of wastes collected in Kolari and the Ylläs tourist center is analyzed and the biogas potential is estimated. Seasonal variations in waste amounts were significant and were found to correlate with the number of tourist visits.

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Authors: Marija Šperac, Anamarija Rabi and Dimitrije Stojkovič

Today, landfills can be defined as a facility that was built and equipped for continuous controlled, organized and safe disposal of waste. Solving the problem of waste disposal requires an interdisciplinary team of specialists who will work together to reach an optimal technical solution and a general social acceptance of such a facility. Common Hazardous Management Facility goes through four phases: project definition, preliminary assessment of the impact of site selection, environmental assessment, decision making and implementation. The effects of landfill on the environment can be measurable and immeasurable. Methods for defining these impacts are: net present value method, the method of assessment experts, multicriterial analysis.

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Pollution of the natural environment by heavy metals is a universal problem because these metals are indestructible and most of them have toxic effects on living organisms, when permissible concentration levels are exceeded. The degree of contamination in the sediments of the Smolnik creek, for the metals Ca, Mg, Fe, Mn, Al, Cu, Zn, As, Cd and Pb, has been evaluated using Enrichment factor (EF), Pollution load index (PLI) and Geo-accumulation index (Igeo). The sediments have been found to be contaminated with Pb, Cu and As which has been attributed mainly acid mine drainage from abandoned shaft Pech (the mine Smolnik) since no major industrial establishments are present in the area.

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Diverting household waste from landfill had become a must for EU member states. The mechanical and biological treatment of household wastes is one of the key method to reach this goal. The object of the mechanical handling is to separate the recyclable fraction and transform the non-recyclable part into Refuse Derived Fuel (RDF) for energetic use and produce fraction for biological treatment. Our challenge to identify the ideal technology for RDF production for the North-Balaton Regional Waste Management System, by studying the existing technologies, and emerging needs from the growing market especially for Cement Industry and pyrolitic technologies.

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The EU has accepted the Waste Framework Directive (WFD) in 2008 setting a 50% recycling target for paper, plastic, glass and metal waste by 2020 and prescribing the obligatory initiation of selective collection by 2015 [1]. These targets are also embedded in the 3rd National Environmental Program of Hungary [2] and the new Waste Management Act proposal. This research is focused on identifying the factors influencing the efficiency of complex selective collection systems. The initiation of a selective collection system results in an increase in recyclables and a decrease in the amount of residual waste. The cost of complex collection system is mainly determined by time of collection and the length of the route of the garbage truck.

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Sparsely inhabited Nordic regions, especially in rural areas, offer a great potential for renewable energy production. Waste-to-energy (W2E) technologies can play a very important role in the diversification of the energy production portfolio in the framework of a growing energy demand. In this paper, we examine the role the development of a smart energy network can play to support the employment of W2E technologies for sparsely populated rural areas. It is expected that W2E technologies combined with smart energy grids would make sustainable energy solutions viable and economically feasible, whilst supporting a transition to a sustainable energy strategy.

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Authors: Marcela Ondova, Nadezda Stevulova, Lenka Palascakova and Adriana Estokova

The current annual worldwide production of by-products is estimated about 700 million tons of which 70 % is fly ash at least. Large quantities of fly ash are available at low costs around the world and its use in concrete seems to offer the best solution to reduce its consumption. With regard to these facts and Slovak needs, the chemical and mechanical properties of hardened concrete composites with various share of fly ash were studied. Other focus of this study is the investigation of the influence of different chemical admixtures on development of the concrete properties, their environmental and economic impacts.

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Authors: Danko Fundurulja, Lidija Tadič and Tamara Dadič

This paper gives an example of a potential waste management centre construction in the Osijek-Baranja County. First, the existing situation regarding waste management was established (quantity and composition). Today, waste is disposed on 9 ‘official’ landfills and a series of ‘unofficial’ ones. Considering the unsustainable nature of the present condition, which is contrary to the applicable Croatian regulations, efforts have been made to develop a solution with the aim of building a single waste management centre. The projections regarding mobility, generation, collection and disposal of waste for a period of 30 years are provided.

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Authors: Valeria Nagy and Attila Meggyes

Production and utilization of renewable energy sources (e.g. biogas) are justified not only by energy-political, but by environmental aspects, too. It can be verified the necessity of the complex ecological aspects by biogas production experiments and its utilization tests in gas engines therefore we created a complex biogas production and utilization system, so that both the energy and the environmental goals can be achieved together. In the interest of an optimal solution it is necessary to analyze the two objective functions (the production and utilization functions) together, considering that the principle of the complex optimization focuses just on the environmental-friendly energy utilization. The centre of this system is the integrated waste-management. Its advantages are the local and global environmental results, energy production independent of external influences, as well as a near optimum solution ecologically.

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Abstract

A net zero-energy building (NZEB) is considered as a resident or commercial building where the energy needs are covered by using locally available renewable energy sources and technologies. Various types of heat pumps are widely used energy conversion systems for NZEB strategies implementation. This paper is focused on the development of a novel LabView-based model for an air-source heat pump system that absorbs heat from outside air and releases it inside the building as domestic hot water supply or room's space heating by using hot water-filled fan-coils. In the first research steps the mathematical background of the considered heat pump system has been developed. Then the LabView-based software implementation of the air-source heat pump and entire heating circuit model is unfolded and presented. The result is a versatile and powerful graphical software toolkit, suitable to simulate the complex heating, ventilation and air-conditioning processes in net-zero energy buildings and to perform energy balance performance evaluations. Beside the elaborated mathematical models, a concrete software implementation example and measurement data is provided in the paper. Last but not least, the proposed original model offers a feasible solution for future developments and research in NZEB applications modeling and simulation purposes.

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Authors: E. Kovács, P. Tóth, Cs. Juhász and J. TamáS

Abstract

There are numerous biological agents including bacteria such as Brucella suis, B. abortus, Francisella tularensis, Burkholderia mallei, Coxiella burnetii, Yersina pestis, Bacillus anthracis and Chlamydia psittaci, viruses such as Variola major and V. minor, Flavivirus and Hantavirus, and toxins such as Botulinum toxin produced by the bacterium Clostridium botulinum, Staphylococcus enterotoxin B and Trichothecene mycotoxin reported to have potential to cause illness via water consumption. In the recent years, biological threat prevention for urban water supply systems has been of special interest worldwide, thus, protection against biological agents requires adequate knowledge, available water treatment technologies and preparedness. In this review, the history of biological threat via public water supply, as well as selected early detection methods, prevention strategies and risk assessment models are detailed.

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Abstract

The recycling of greywater for non-potable water applications, such as toilet flushing or irrigation, is a potential solution to reduce potable water consumption. To estimate the quality of raw greywater samples, we measured several physical, chemical and biological parameters. We used Hygiene Monitor test kits to determine microbiological presence in the samples. The greywater samples showed a high variability for all the measured parameters. In general, we found that greywater sources had lightly alkaline character with a considerable inorganic and organic content. About half of the analyzed samples can be characterized as highly contaminated water source with organic substance. The average BOD5 and DOC values of greywater samples were 429 ± 410 mg l−1 and 341 ± 348 mg l−1. The samples showed high similarity concerning the total plate counts parameter (range from 5 to 6 log10 cfu ml−1). Among the three greywater sources, the samples from dish sources showed the lowest coliform content (3.9 log10 cfu ml−1) and the bath samples were contaminated with coliforms to the highest degree (4.9 log10 cfu ml−1). The results of E. coli contamination tests proved that all greywater sources can be contaminated with pathogen bacteria, consequently the treatment before reuse of greywater is indispensable.

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Abstract

This study presents the examination of the leadership in a multi-national company in Debrecen, in which we examine the relationship between lean and leadership. We identified the competitiveness within a kaizen implementation of the company's moderators with the help of a questionnaire. With help of the identified management competencies we determine the leadership style, which is necessary for the operation of a successful and effective lean management.

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Abstract

In this study the financial situation of leading Hungarian construction companies in Hajdú-Bihar County is analysed for the period of the economic crisis. The target group is determined by the amount of share capital and sales, thus it contains the most relevant regional companies. Their main activity is residential and non-residential building construction. The most significant purpose of the research is to analyse the changes of the comparative financial situation of these companies. Moreover, I specify the main characteristics of the regional sector, and determine the competitive advantages of the companies. The research method is based on annual financial reports. In order to evaluate the performance of the examined companies I use financial ratios concerning liquidity, efficiency, and profitability situation. At the end of the study I summarize conclusions and identify the most important consequences regarding the changing financial position of competitors.

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Abstract

In this paper we analyse the trends and developments of energy imports as a percentage of gross inland energy consumption including bunkers in Hungary and the European Union countries between 2000 and 2011. Data show that the average of the energy dependence increased in the EU27 Member States (7.1 percentage points) and in Hungary, too (3.4 percentage points). The energy intensity in Member States is examined as well. According to the data the energy intensity decreased in the majority of the Member States, the average decreased by 16 percent.

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Authors: F. Mata Cabrera, J. Tejero Manzanares, I. Hanafi, A. B. Arenas, I. Garrido, V. Toledano and M. L. Rubio

Abstract

Mechanical properties of ductile materials are very sensitive to environmental conditions in particular temperature. The paper shows the results obtained in the simultaneous testing of 5182 H111 Aluminium alloy, S275JR Carbon Steel and F114 Carbon Steel specimens using conventional methods and thermography. The infrared thermography was used to quantify deformation localization zones, also to relate the temperature changes of the specimens, continuously recorded by thermography, with the load extension diagram. It enables to predict reaching the critical stresses which cause the appearance of fractures and to define the criteria for determining the maximum sample temperature alteration in the field of elastic and elastic-plastic strains. Infrared thermography was found to be an efficient tool for investigating the deformation and damage scenario under tensile loading.

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Authors: N. Mazsu, A. Szabolcsik, S. Forian, N. Boros and I. Bodnar

Abstract

Several small and big water streams cut across Hungary; the protection of these water resources is in our common interest. To perform this protection, it is necessary to carry out extensive condition surveys of these surface waters. Unfortunately, our surface water streams are not properly investigated; it is true especially for the small ones. That is why we started to study the water quality of Nagy Brook, which is loaded by many point sources of pollution. During our work we have done measurements on spot and in laboratory, as well. In this paper we are presenting only those results which were measured on the spots along the Nagy Brook. Our results demonstrate how large the effect of inflowing treated wastewater is on the quality of a seasonal water stream and how the water level affects the studied parameters and what kind of the chemical and ecological water conditions can be developed under these circumstances.

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Abstract

The papers of the series deal with experimental characterisation of mechanical as well as structural properties of different steel fibre reinforced concretes that can be used for several structural applications. An extensive experimental programme (six years) has been developed to investigate the effect of steel fibre reinforcement on the mechanical performance and structural behaviour of concrete specimens. Specimens and test methods were selected to be able to detect realistic behaviour of the material, representing clear effect on the structural performance. Material compositions, test methods, type of test specimens will be detailed in the presented paper (Part I).

Furthermore, compressive strength (Part II), stress-strain relationship (Part II), splitting strength (Part III) and toughness (Part IV) will also be discussed. In the light of the motivation to determine the structural performances of 1D concrete structural element affected by steel fibre reinforcement, bending and shear behaviour (Part V) as well as serviceability state (Part VI) of steel fibre reinforced concrete beams will be analysed. Since normal force — prestressing force — can affectively be used to improve the structural performances of RC element flexural tests were carried out on prestressed pretensioned steel fibre reinforced concrete beams (Part VII). Moreover, focusing on the in-plane state of stresses for 2D structures, behaviour of steel fibre reinforced concrete deep beams in shear and steel fibre reinforced concrete slabs (Part VIII) in bending will be explained. Finally, based on the wide range of the experimental and analytical studies on the presented field, a new material model for the 1D uniaxial behaviour (Part IX) and its possible extension to the 3D case (Part X) will be described hereafter. All papers will put emphasis on the short literature review of the last four decades.

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Abstract

The present paper of a series deals with the experimental characterisation of compressive strength and compressive behaviour (stress-strain relationship) of different structural concrete containing different volume of steel fibre reinforcement (0 V%, 0.5V%, 1.0V%, 75 kg/m3, 150 kg/m3) and different configuration of steel fibres (crimped, hooked-end). Compressive tests were carried out on standard cube (150 mm × 150 mm × 150 mm) and cylinder (Ø = 150 mm, l = 300 mm) specimens considering random fibre orientation. Since the fibre orientation may significantly affect the compressive behaviour, test series were also performed on cylinders (Ø = 70 mm, l = 100 mm) drilled out of fibre reinforced concrete beams and prisms (100 mm × 100 mm × 240 mm) sawn out of steel fibre reinforced deep beams. Throughout the tests stress-strain relationships were registered on the standard cube and cylinder specimens as well. In conclusion, behaviour of steel fibre reinforced concrete was examined in compression taking into consideration different experimental parameters such as fibre content, type of fibres, fibre configuration, fibre orientation, size of specimens (size effect) and concrete mixture.

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The sensory quality of red wines is basically determined by the colour, which depends on the amount and on the evolution of anthocyanins and other phenolic compounds extracting from the berries into the wine during wine-making. The anthocyanin-monomers are responsible for the development of the red colour, and their acylated derivatives provide stability for the colour of the wines. The anthocyanin profile of wines is affected by several factors: the grape variety, the conditions during wine-making, and also the yeast culture used for the fermentation. In our experiments a self-compiled model solution was fermented by spontaneous fermentation, as well as by four commercial yeasts under laboratory conditions. After fermentation total polyphenolics, anthocyanins, anthocyanin monomer profile, colour intensity, hue, and the ratio of polymeric anthocyanins were studied. Our results show that the spontaneous yeast fermentation resulted in a higher anthocyanin concentration in the fermented model solution, but the commercial yeast strains provided a more advantageous colour characteristic compared to the spontaneous fermentation. After the spontaneous fermentation less sediment was left than in the commercial yeast fermented samples.

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Composite flours were formulated from wheat flour and additives containing high amylose starch, resistant starches of RS2 and RS3 types, and barley β-glucan. Different parameters of flours, doughs, and final breads were evaluated. Almost all composite flours had significantly worse parameters as flour and dough in comparison to control. Sensory parameters of breads were also lower, though loaves supplemented with up to 15% (w/w) of high amylose starch (Hylon® VII), RS2 (Hi-maize™ 260), and RS3 (Novelose® 330) were considered as acceptable, with higher content of RS observed. Loaves with β-glucan (Barliv™ barley betafiber) were not acceptable either in sensory or technological parameters.

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The moisture, protein, fat, and ash contents of Barbus grypus muscle were 76.14, 18.85, 2.95, and 0.83%, respectively. The fatty acid composition of B. grypus showed that the amounts of saturated fatty acids (SFA) were significantly (P<0.05) higher (34.88%) in the liver compared to the muscle (30.18%). Of the SFA, the amount of palmitic acid was significantly (P<0.05) higher in the liver than that in the muscle and gonad. With regard to the monounsaturated fatty acids (MUFA), oleic acid content in the muscle (23.46%) of B. grypus was significantly (P<0.05) higher than in the liver (18.01%). The amounts of docosahexaenoic acid (C22:6 n-3, DHA), eicosatetraenoic acid (C20:4 n-3), and eicosapentaenoic acid (C20:5 n-3, EPA) were predominantly found in the muscle, liver, and gonad. The amount of cholesterol in the liver and gonad was significantly higher than in the muscle. On the other hand, significantly higher (P<0.05) retinol, D3, δ-tocopherol, and K1 vitamin values were found in the liver than in the muscle and gonad of this species.

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Mice (Balb/c), with peanut allergy induced, were subjected to desensitization therapy with the use of pea protein extract (PE) or isolated globulin fractions: legumin (PL) and vicilin (PV). B- and T-cell responses to peanut proteins were analysed by determination of the IgE, IgG1, and IgG2a antibody levels in plasma and the concentration of IL-4, IFN-gamma and IL-10 cytokines secreted by isolated splenocytes.Conducted studies have demonstrated that immunotherapy with proteins resulted in the decrease of total IgE and peanut-specific IgG1 levels and significantly enhanced synthesis of peanut-specific IgG2a in plasma (ELISA method) and at the cellular level (ELISPOT type B). A successful and effective immunotherapy is related to the shift in profile of lymphocytes from Th2 subpopulation towards Th1 subpopulation. In our studies significant increase in the activity of Th1 lymphocytes was observed in groups desensitized with pea protein extracts (PE) and pea legumin fraction (PL). In these groups, significant statistic decrease in IL-4 secreted and increase in IL-10 level were found.Desensitization method with the use of pea proteins being suggested in the presented studies can be an alternative method for specific immunotherapy for people, especially with strong allergic reaction to peanuts; however, this method needs further studies with mouse model.

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Vitamin B6 analysis by reverse-phase high performance liquid chromatography and its validation in milk powder prompted this study. The calibration curves for pyridoxal, pyridoxamine and pyridoxine were evaluated and method precision and accuracy assessed. It was found that the working range was adequate for all the analytes. The analytical procedure was verified by testing the enzymatic efficiency, precision and accuracy. In milk powder samples pyridoxine was the only vitamer found in quantities above the considered limit of quantification and the accuracy showed Z-scores lower than 2. Uncertainty estimation based on method validation results was 0.066 mg/100g, for a vitamin B6 content of 0.61 mg/100 g. It was concluded that the method is adequate for vitamin B6 quantification in powder milk.

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This study aimed to evaluate the coating effect of methacrylic acid copolymers (MAc) on alginate beads, with respect to protection, survivability, and in vitro release of lactobacilli cells under simulated gut conditions, and to evaluate the effect of oven drying and fluidized bed-spraying as a mean to dry and coat alginate beads with MAc. MAc-coated beads exhibited protective effects for lactobacilli cells against low acidic environment providing higher survivability (71.82–96.11%) compared to uncoated beads (28.67–61.68%), and also higher cell release under sequential gut conditions (P<0.05). Lactobacillus casei BT 1268 showed a high cell release and was thus selected for further analysis using spray coating-drying via fluidized bed. Scanning electron microscopy revealed that fluidized bed-spray drying produced beads with irregular shapes but consistent coating and with lactobacilli cells clearly embedded within the inner matrix. Oven dried and fluidized bed-spray dried MAc-coated beads of L. casei BT 1268 also showed similar cell release, indicating the possible use of fluidized bed-spray as a more economical and less time consuming method for the protection and maintenance of cell viability.

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In this work the influence of addition of different plant extracts (olive leaf, green tea, pine bark PE 95%, pine bark PE 5:1, red wine PE 30%, red wine PE 4:1, and bioflavonoids) to blackberry juice during heating (at 30, 50, 70 and 90 °C) on the anthocyanin and phenol contents, polymeric colour, and antioxidant activity was investigated. Also, reaction rate constant, half-lives of degradation, and activation energy were calculated. Control sample was juice without addition of extracts. The highest anthocyanin content at 30 °C was in samples with the addition of olive leaf and green tea. At 90 °C the highest anthocyanin content was measured in samples with the addition of extract of red wine and bioflavonoides. Samples supplemented with the extracts had much higher antioxidant activity in comparison to the control sample. Results showed that at 90 °C the sample with green tea supplementation had the lowest reaction rate constant and the highest half-life. Activation energy ranged from 29 to 44 kJ mol−1.

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The fruit quality parameters of Prunus armeniaca L. cv ‘Ninfa’ grafted on ‘Myrobalan 29C’ (Prunus cerasifera Ehrh.) and ‘Real Fino’ apricot seedling (Prunus armeniaca L.) were analysed in an experimental orchard under organic management. The study was performed between 2010 and 2012 in the province of Seville (SW Spain). Colour, fruit and stone weights, firmness, soluble solid concentration, and acidity were measured for fruit quality evaluation. Trunk cross-sectional area, main branches, and fruit yield were also determined. In general, ‘Myrobalan 29C’ rootstock produced fruit slightly larger in size and with a bigger weight. By contrast, apricots on ‘Myrobalan 29C’ had less firmness and a lower solid soluble concentration than on ‘Real Fino’. There was little difference in the colour, acidity, and stone dry weights. Trees on ‘Real Fino’ had larger areas of trunk and branches but no significant differences were obtained in relation to fruit yields.

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The article analyses patterns and country-specific determinants of Visegrad Countries’ agri-food trade with the European Union. Literature focusing on the country-specific determinants of vertical and horizontal intra-industry trade is rather limited and those analysing agricultural (or agri-food) trade are extremely rare. Therefore, the paper seeks to contribute to the literature by covering the latest theories and data available on the topic to provide up to date results and suggestions. Moreover, it seeks to identify the determinants of horizontal and vertical intra-industry trade of the Visegrad Countries after EU accession. According to the results determinants of horizontal and vertical intra-industry differ and suggest that economic size is positively, while distance is negatively related to both sides of intra-industry trade. However, the relationship between vertical intra-industry trade and differences in factor endowments as well as foreign direct investment is ambiguous.

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The present study was undertaken to assess the effects of gamma irradiation (0, 2, 4, and 6 kGy) on microbial, chemical, and sensory values of Jabaly Syrian goat meat during storage at 4 °C for 1, 3, 4, and 5 weeks. Irradiation was effective in reducing the microbial load and increasing the shelf-life of goat meat. The radiation doses required to reduce the microorganisms by 90 percent (D10) in goat meat were 294 and 400 Gy for Salmonella and E. coli, respectively. The main fatty acids identified from the goat meat were oleic, stearic, and palmitic acids. No significant differences were observed in moisture, crude protein, crude fat, ash, pH value, fatty acids, total acidity, volatile basic nitrogen, and sensory properties (texture, flavour, colour, and taste) of irradiated and non-irradiated goat meat. Lipid peroxidation measured in terms of thiobarbituric acid-reactive substances (TBARS) increased on irradiation and chilled storage. Sensory evaluation showed no significant differences between irradiated and non-irradiated goat meat.

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Authors: M. Abbas Ali, Z. Bamalli Nouruddeen, I. Idayu Muhamad, R. Abd Latip and N. Hidayu Othman

The aim of the present study was to investigate the effects of palm olein (PO) addition on the quality characteristics of sunflower oil (SFO) during frying of potato pieces. The blends were prepared in the volume ratios of 20:80 (PO:SFO, PSF1) and 40:60 (PO:SFO, PSF2). Refractive index, free fatty acid content, peroxide value, p-anisidine value, TOTOX, viscosity, specific extinction, polar compounds, food oil sensor value, colour, and polymer content of the oils all increased, whereas iodine value and C18:2/C16:0 ratio decreased as frying progressed. The percentage of linoleic and linolenic acids tended to decrease, whereas the percentages of palmitic and oleic acids increased. Based on the most oxidative stability criteria investigated, PO addition led to a slower deterioration of SFO at frying temperature. Blend PSF2 showed better frying performance compared to PSF1. However, higher amounts of free fatty acids and higher colour units were both detected in the blends compared to pure SFO at the end of frying. It appears that proper blending of highly unsaturated SFO with PO can result in oil blends that could meet nutritional needs with improved stability for domestic cooking and deep-frying.

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Authors: S. Valcheva-Kuzmanova, M. Eftimov, R. Tashev, L. Yankova, I. Belcheva and S. Belcheva

The main bioactive substances in Aronia melanocarpa fruit juice (AMFJ) are polyphenols (flavonoids, procyanidins, and phenolic acids). A great number of polyphenols are able to traverse the blood-brain barrier. In recent years more attention is drawn to the ability of these substances to influence central nervous system functions. The aim of the present study was to investigate the effects of AMFJ on exploratory behaviour and locomotor activity in male Wistar rats. AMFJ was administered orally for 7, 14, 21, and 30 days at three increasing doses (2.5, 5, and 10 ml kg−1). The changes in exploratory behaviour and locomotor activity were recorded in an Opto Varimex apparatus. It was found that the low doses of AMFJ (2.5 and 5 ml kg−1) for all treatment periods did not significantly affect exploratory behaviour and locomotor activity of rats compared to the saline-treated controls. AMFJ at the highest dose of 10 ml kg−1 had no significant effect on exploration and locomotion for the treatment periods of 7 and 14 days, while for the periods of 21 and 30 days it significantly decreased the number of horizontal and vertical movements, which might be the result of a sedative effect. At all the doses and testing periods, AMFJ did not disturb the progressive decrease in motor behaviour, suggesting habituation.

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The oral administration of hyaluronic acid has been shown to improve skin health. This study aimed at utilizing ultrasound treatment to enhance the production of hyaluronic acid by lactobacilli. Among the 16 strains of lactobacilli screened, a higher production of hyaluronic acid (P<0.05) was observed from seven strains namely, Lactobacillus casei BT 2113, Lactobacillus casei BT 1268, Lactobacillus casei BT 8633, Lactobacillus casei FTDC 8033, Lactobacillus acidophilus FTDC 1231, Lactobacillus gasseri FTDC 8131 and Lactobacillus rhamnosus FTDC 8313. Upon ultrasonic treatment, hyaluronic acid concentration increased significantly (P<0.05) in all the seven strains studied. The use of ultrasonication at 100% amplitude increased the hyaluronic acid content (P<0.05) up to 51.6 % with concentrations ranging from 0.262 mg ml−1 to 0.385 mg ml−1, while an amplitude of 20% yielded a lower increase ranging from 0.227 mg ml−1 to 0.310 mg ml−1. Increasing duration of ultrasonic treatment (from 1 min to 3 min) also significantly (P<0.05) improved the concentration of hyaluronic acid in some strains. Our data demonstrated that a sub-lethal physical treatment, such as ultrasonication, can be applied to increase the membrane permeability of lactobacilli cells and subsequently increase the release of bioactive metabolites.

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Authors: Á. Tölgyesi, J. Fekete, V.K. Sharma, É. Pálffi, K. Békési, D. Lukonics and G. Pleva

A new liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to confirm chloramphenicol (CAP) residues in foods of animal origin and in urine samples, which were earlier found positive under the screening analysis, performed by competitive enzyme-linked immunoassay (ELISA) technique. The developed LC-MS/MS method was applied to four non-compliant samples from 2008 to 2012; giving concentrations of CAP residues from 1.18 to 3.68 μg kg−1. All samples, qualified positive by ELISA, were confirmed with the LC-MS/MS technique and found to be non-compliant. The effectiveness of the confirmatory method was proven by participating in a successful proficiency test in year 2010. Both LC-MS/MS and ELISA methods were validated according to the European Union 2002/657/EC decision. The decision limit of the confirmatory method was determined as 0.02 μg kg−1 for CAP in each validated matrix, while the detection capability of the screening test was 0.15 μg kg−1.

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The present study was carried out to examine the antioxidant activity in oyster mushroom cultivated on selenium (Se) rich substrate. Pleurotus fossulatus was cultivated on Se-rich wheat straw collected from the seleniferous belt of Punjab (India) and its potential to accumulate Se from substrate was examined. Using different assay systems the modulations in the anti-oxidant profile of Se enriched mushroom was studied in comparison to the mushrooms cultivated on normal straw. The oyster mushrooms were observed to potentially mobilize Se from Se-rich substrates to fruiting bodies, resulting in significantly high uptake (37.2±0.6 μg g−1) as compared to control (3.57±0.53 mg g−1). The antioxidant activity, as determined by various assays, such as reducing power, 2,2-diphenyl-1-picrylhydrazyl free radical scavenging, and metal chelating activity, was higher in the experimental mushrooms when compared to control. The results obtained demonstrate that Se-fortified mushrooms through cultivation on straw containing organic forms of Se can be considered as natural and effective dietary supplements of organic Se for humans. The present study proposes the use of Se-rich agricultural residues as substrates for mushroom cultivation for human and livestock supplementation.

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Four kinds of lamb meat foods (Wiener sausage, ham, roasted meat, and roasted leg) were developed based on 8 different genotypes to improve lamb meat quality and quantity, and to study the differences among them. The stringiness, flavour, and odour of the products were judged in food sensory evaluation by a total of 265 (60% male and 40% female) randomly selected consumers. In stringiness and flavour five (from 1 to 5), and concerning odour three (from 1 to 3) categories were created according to decreasing quality. The consumers represented different age groups: below 20 years, between 21–30, 31–40, 41–50, 51–60, 61–70, and above 70 years. The groups of consumers were involved in sheep farming, other animal farming, other agriculture sector, industry, catering, education, other service; administrative department of the state, were students, and others. Analyses of variance were calculated to estimate the effects of the genotype of lamb, the gender, age, and occupation of judging consumers on the sensory evaluation of the meat foods. In conclusion, new lamb meat foods were highly appreciated by consumers, who made definite distinctions among genotypes according to flavour, stinginess, and odour. There were significant interactions between gender, age, and occupation of consumers as well as sensory evaluation of various lamb meat foods.

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Implementation of sourdough technology would increase nutritional value and attractiveness of gluten-free bread. However, fermentation process requires stimulation. The course of fermentation of gluten-free sourdoughs prepared from maize and soy flours and maize and potato starches, enriched in glucose and casein hydrolysate or soy sprouted seeds used as fermentation enhancers was evaluated. The clearest effect of the supplementation was observed in the case of sourdough prepared from starches only. The addition of glucose in the amounts as low as 0.5% has proved to be enough to enhance fermentation effectively. Supplementation of the sourdoughs with peptides was not very effective; however, when used together with glucose, a synergistic effect could be detected. The addition of sprouted seeds allowed to shorten the fermentation process with up to several hours. These studies have demonstrated possibility to simplify and shorten the process of gluten-free sourdough fermentation by modification of mixtures composition.

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Authors: N. Carbonera, M.L. Mitterer-Daltoé, M.I. Lohfeldt, L.S. Pastous-Madureira, M.L.P. Espírito Santo and M.I. Queiroz

The objective of this study was to evaluate the acceptance of fermented anchovy (Engraulis anchoita) by consumers aged 18–67 (n=100) from two experiments, first using preference test and then by acceptance of formulation preference. Anchovy fillets were fermented with added NaCl and glucose with 4 different treatments: A (NaCl 1% and glucose 4%), B (NaCl 1% and glucose 6%), C (NaCl 1.5% and glucose 4%), and D (NaCl 1.5% and glucose 6% glucose). At first, the preference of fermented anchovy fillets with samples prepared in the form of pizza was assessed by applying a preference ranking test to 75 consumers. The results indicated the sample with 1% NaCl and 6% glucose as the preferred (P>0.05). Later in the second stage, the preferred fermented fillet was subjected to acceptance by 100 consumers who have the consumption habit of such product by using a hedonic scale of 9 points. The results indicated an acceptance rate of 79.8%. This work aimed to call attention to the importance of the acceptance of this food.

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