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This paper measures the performance of cooperative spectrum sensing, over Rayleigh-fading channel and additive white Gaussian noise, based on one-bit hard decision scheme for both AND and OR rules. Three measures based on energy detection are considered including effect of false alarm probability, effect of number of users, and effect of number of samples. Simulation results show that the detection probability increases with increasing false alarm probability, number of users, and number of samples for both AND and OR rules. Also, the performance of OR rule is better than the performance of AND rule.

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Bacillus subtilis natto is a potential source of fructooligosaccharides (FOS), which can be obtained by fermentation and may stimulate the growth of beneficial microorganisms in the colon representing a strategy to manipulate the intestinal microbiota acting as a prebiotic compound. The present study focuses on the ability of Lactobacillus ssp. strains to utilize FOS as a sole energy source. The results showed that FOS was equally good as glucose to provide energy source. The highest prebiotic activity score was obtained with Lactobacillus plantarum ATCC 14917 grown on FOS (0.526), followed by Lactobacillus casei (LC-1) (0.222). The lowest score was for Lactobacillus paracasei ATCC 27092 (−0.051). The results suggests that specific combinations of probiotic (L. plantarum ATCC 14917 and L. casei (LC-1)) and prebiotic (FOS) could be used as synbiotics in dairy and other foods.

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Authors: A. Torbica, D. Horvat, D. Živančev, M. Belović, G. Šimić, D. Magdić, N. Đukić and K. Dvojković

The aim of this study was to compare efficiency of RP-HPLC (Reversed-Phase High-Performance Liquid Chromatography) and LOC (Lab-on-Chip) methods for wheat gluten protein quantification regarding clustering of wheat cultivars according to the genetic similarity (HMW-GS combinations), as well as to explore relations of these two methods to wheat quality parameters. For that purpose, wheat quality parameters (protein content, falling number, wet gluten content, gluten index, Farinograph, Extensograph, and Amylograph), as well as amounts of gliadin and glutenin fractions by RP-HPLC and LOC methods were determined in two different sets of wheat cultivars (Croatian and Serbian). The percentages of gluten proteins and the values of quality parameters were used to characterize the samples by principal component analysis (PCA). Gluten protein quantification performed by method based on the protein fraction separation by molecular weights (LOC) was better for grouping of genetically similar wheat cultivars than quantification of proteins separated by their different solubility in specified solvent gradient (RP-HPLC). LOC method showed higher potential in wheat quality prediction.

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The turbulence intensity is an important feature of the turbulent airflow and draught sensation in ventilated rooms. The turbulence is often measured with hot-wire (in fluid mechanics applications) and hot-sphere sensors (in indoor air comfort investigations). In this paper the turbulence was measured with hot-wire and hot-sphere sensors in a full-scale single office room based on air speed measurements. Isothermal air injection was applied and the measurements were conducted on eight different inlet volume flow rates. The two applied sensors resulted two independent samples, which were evaluated with different statistical methods. The results showed that there was not significant difference between the standard deviation and average of the measured samples. Thus, the two sensors statistically gave the same results on probability level 95%.

The referred international standards suggest an average turbulence intensity 40% for draught comfort design in mixing ventilation. The results showed that most of the measured turbulence intensities were less than the recommended standard turbulence intensity.

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Solar power is the conversion of sunlight into electricity, using photovoltaic (PV) solar panels. This paper introduces the solar power station in Fish Country, in Hungary. The examined solar power station (50 kWp) consists of 200 pieces of polycrystalline silicon Kyocera solar panels. The efficiency of this power station was measured and calculated in order to determine its amortization period and the amount of prevented CO2 emission as a consequence of this technology. The results of the measurement and calculation of the efficiency demonstrate that the facility fulfils the committed requirements. Nowadays, the air pollution is considered as one of the major causes of the global warming. This is reflected by the EU restriction of the emissions. The solar power station, which was built by Aranyponty Halászati Ltd., contributed to reduce the local CO2 emission, but it has impact on the global level as well, because circa 50 tons of carbon dioxide is prevented to be emitted into the atmosphere per year.

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Thermal bridging caused by exposed concrete balcony slab is a major source of heat loss through energy efficient building envelopes. Moreover, thermal bridging can also create moisture management and indoor comfort challenges. Numerous investigations have been carried out to reduce heat transmittance through exterior building envelopes and minimize the energy use in buildings. The most effective way to minimize heat transmittance of exposed concrete balcony slabs is to thermally separate the exterior structure from the interior structure using thermal breaks. To enhance thermal separation, this paper investigates the effects of replacing high conductive materials such as reinforced concrete or structural steel with a multilayer composition of high-performance hybrid insulating systems. Reinforcing bars, such as fiber reinforced plastics (FRPs), having lower thermal conductivity than steel are used to connect interior to exterior and transfer loads. Numerical simulation tool THERM is used to study the effects of thermal breaks on energy performance of the concrete slab balcony joints. Simulation results indicate significant thermal performance improvement while high-performance hybrid insulating systems were used for exposed concrete balcony slab constructions, compared to traditional insulating systems used in similar constructions

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Authors: F. Békés, K. Ács, Gy. Gell, Cs. Lantos, A-M. Kovács, Zs. Birinyi and J. Pauk

Consumption of “gluten-containing” diet causes disease for a significant minority of people who consume foods derived from wheat, rye, barley, and possibly oat. The fact is, however, that in several types of diseases related to the consumption of “gluten-containing” cereals, the trigger compounds are not components of gluten. The current view of medical experts is that, excluding people suffering from celiac disease, the majority of individuals who are feeling better on the “wheat-free” or “gluten-free” diet could select a food containing much healthier, low level of fermentable oligosaccharides (often called as FODMAP). To satisfy the specific health related demands of certain consumer groups, the challenge is in front of cereal breeding to develop new, “healthier” germplasms, suitable to produce such products by the food industry. This report aims to give an overview of some aspects of recent developments in this booming area, (i) summarizing the up-to-date knowledge on cereals-related health disorders; (ii) reporting on the status of developing celiac-safe cereals, and finally (iii) highlighting the potential of developing “healthier” spelt-based cereal products through the progress in an ongoing spelt breeding program.

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Consumption of dietary supplements (DS) has been showing a persistent, rapidly growing tendency all over the world. A new branch has been created on the borderline of food and pharmaceutical industries. It is a general tendency that the policy and regulation towards the products of this branch are lagging far behind the practice. This is an especially important problem with adolescents. To work out an efficient regulatory framework, we have to have an adequate picture on consumer behaviour and attitudes towards these products. Based on literature analysis of two focus group interviews, we have developed a motivational model on usage of DS, which has been tasted during a direct-question survey involving more than 500 respondents. Our results have proven that the consumption of DS is proliferated among young recreational athletes. One quarter of them consumes proteins, one tenth L-carnitine at least 2–3 times a week. The most important motivational factor is the improvement of sport performance. The level of confidence in these products is considerably influenced by peers and trainers. The propensity to underestimate the potentially adverse consequences of these products is high.

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Authors: A. Castro, C. Palhau, S. Cunha, S. Camarinha, J. Silva and P. Teixeira

Staphylococcus aureus is considered a global community and health care pathogen responsible for staphylococcal food poisoning. The aim of this study was to characterize several isolates of S. aureus recovered from different food products concerning enterotoxin genes and other virulence factors including antimicrobial resistance. In 2009, a total of 78 coagulase-positive staphylococci from 1454 food samples were identified to species level; 73 were confirmed as S. aureus. Of the S. aureus isolates 5.5% were resistant to oxacillin, 52.0% showed resistance to erythromycin, and 45.2% to tetracycline. Multidrug resistance was observed in 33.3% of the isolates (resistance to three or more antibiotics of different classes). SCCmec types IV and V were detected among methicillin-resistant S. aureus (MRSA). One MRSA isolate was pvl positive. The 52.0% of food isolates were shown to be enterotoxigenic; egc (63.0%), secbov (44.7%) were the main detected SEs. tst gene was also detected in food isolates. The present work demonstrates the presence of virulent S. aureus collected in 2009 in foods.

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In Kosovo, originality often meant leftovers inherited from other cultures during centuries of invasion and dominance under the Ottoman Empire. Considering the multinational and multicultural character of Kosovan society and its diversity of religions, Roman Catholic and Orthodox religious buildings cannot be disregarded either. The respect for tradition and the existing environment, including architecture are details to be considered. In this context, the National and University Library could and should be considered a valuable example for the years of general transformation in Prishtina and in all of Kosovo. Even with all the contemporary way of thinking, the traditions, the religion and other regional aspects were not entirely disregarded, especially in the case of the Library building.

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The paper addresses the determination of a stiffness-temperature correction model for the use in a mechanistic overlay design method, developed at the Department of Highway and Railway Engineering, Budapest University of Technology and Economics. Eleven models are selected and evaluated based on 215 laboratory stiffness test results at various temperatures of 47 different AC22 binder course type mixes. As the results showed, for the rough temperature correction of Hungarian binder course mixes for the use in the proposed design method; the model used by the AASHTO 1993 pavement design method is most accurate based on the standard error of the estimate of the selected models.

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This paper has the main focus in energy consumption by the residential sector in city of Prishtina. Considering the fact that the energy production in Kosovo is not sufficient in relation with the everyday demand and at the same time the growth of the energy demand based on different resources is evident, a detailed analysis and identification of the energy performance of this sector is inevitable. One of the main components that cause the energy demand in residential sector is the heating energy demand. The energy resource and heating systems used by the residential sector in city of Prishtina are diverse.

This paper elaborates and identifies the number of residential buildings, number of dwellings, building typologies, heating energy resources, heating systems used by the dwellings and the energy demand for heating energy, by using quantitative methodology. Based on the results achieved by the research, future detailed analysis is possible to identify other components, which affect the heating energy demand by the residential sector. These first results can be used as a basis of the first district scaled energy modeling of the city of Pristhina. By applying the energy management method, developed by Prof. Gerhard Hausladen and his research group at the TU München, a first modeling step will be absolved. After analysis of the current state of the investigated districts, future concepts will be made increasing efficiency and sustainability.

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Authors: Cristian Petruş, Valeriu Stoian, Marius Moşoarcă and Anthimos Anastasiadis

The objective of this study is to evaluate the out of plane behavior of a masonry infill wall provided with an exterior thermal insulation system. For this purpose there were constructed two 1:1 scale specimens of masonry infill walls in order to compare a simple wall with one having already applied an exterior thermal insulation system composed by a polystyrene insulation and a protection layer of plaster and a glass fiber mesh. The load was applied through a horizontal force, acting at the mid height of the wall. Both specimens were tested in displacement control, using alternate force with 3 cycles per loading step. As it was expected, an increased stiffness and out of plane resistance was observed for the wall provided with the insulation system. Various observations were noticed related to the technology and overall behavior of the infill masonry wall.

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Authors: Ivan M. Berezin, Alexandre A. Petunin, Dimtrij I. Kryuchkov and George L. Kovács

A specific process of manufacturing of vessel shell tabs, namely the method of cold stamping is studied in this paper. Recommendations are proposed to gain the proper technology of manufacturing spherical vessels with a volume above 600 cubic meters with regard to labor saving of tabs stamping on hydraulic press. The necessity of having proper technology of stamping is motivated by the large quantity of manual operations, having a direct influence on the conversion costs of a spherical vessel as a whole. The importance of this research is connected with the necessity of multiple shape control of tabs being manufactured during stamping and time-consuming point-by-point shaping-up. The reduction of material costs is supported by using finite-element simulation. Problems are solved with specific modules of the computer aided engineering-system ABAQUS. The results of some finite-element simulations are described. The analysis of stress-strain state at each step of the application of loads is performed.

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This paper deal with the overall heat transfer process and confrontation of experimental measurements and their numerical solutions on simplified model, inside the horizontal scraped surface heat exchanger. The experimental measurements were done on two horizontal scraped surface heat exchangers connected in series. As a product was thermally treated water, heated by vapor in the first stage and cooled by cold water in the second stage. Applied mass flow of the product: m=250, 500, 750, 1000 kgh−1 and rotary velocity of the shaft, scraper blades: rpm=20, 30, (45), 60, 90 min−1. For numerical analyses the simplified model was used, with taking only the area between the heat transfer tube, and the shaft with an aim to compare the result to experimental measurements and validate the obtained overall heat exchange, as justify the simplification. As a results from experimental measurements were obtained the correlations for Nusselt number in a form of Nu=f(Re,Pr,η f/η w). Based on the confrontation of results, it can be stated that the level of simplification used at numerical solutions, gives still an acceptable accuracy of overall heat transfer values. From numerical simulations were obtained further results as the velocity, temperature fields, which were used to make certain adaptation on proposed construction and their examination by additional numerical simulations. All these acquired results lead to better understanding the overall process inside the horizontal scraped surface heat exchangers and the proposed construction of mutators can increase the efficiency of heat transfer process for many products in a real processing.

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The western shoreline of the Danube from Érd to Mohács consists of loess bluffs up to 50 m high. These bluffs can be susceptible to landslides when groundwater conditions weaken the supporting loess. Often this will occur during periods of high rainfall, however morphological, geological and other factors are also important in triggering these movements.

Changes in pore water pressures related to precipitation, confined water levels driven by remote catchments, and river level fluctuations are widely recognized as important factors controlling the loess bank stability. This work aims to determine the interaction of rainfall, river level, drainage and local pumping on the pore pressure regime and stability of the bluffs.

As a first step, a realistic 2-dimensional infiltration and groundwater model was built that reflects the influence of river levels, rainfall patterns, and local pumping. Based on model results, initial and boundary conditions have a strong influence on seasonal pore pressures. Further study will better define those influences on slope stability along the bluffs.

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The international healthcare systems interoperability is an unresolved technological area at the moment. This paper demonstrates the results of the software engineering research for simplex syntactic and semantic technical interoperability of hospital information systems, eHealth smart device technology and clinical telemedicine instruments through the recently developed Telemedicine Interoperability Hub. Several similar experiments exist. This research is unique in building a prototype interconnecting not only healthcare information systems with each other, but aiming to establish a general healthcare interoperability scheme including also the eHealth smart devices and telemedicine instruments. The aim of this research is to establish cloud-based data interchange capability with the newly developed information technology system interconnected with the emerging eHealth Internet of Things solutions and the classical hospital information system architecture. Notwithstanding the international information technology medical data exchange standards, like Health Level Seven, the adoption of an industry-wide open telemedicine syntactic and semantic interoperability standard is necessary. The research studied varying simplex, duplex, full-duplex, data package- and file-based information technology modalities establishing stable system interconnection among clinical instruments, healthcare systems and eHealth smart devices. This research is the manifestation of the trilateral cooperation of the University of Debrecen Department of Information Technology, Semmelweis University Second Paediatric Clinic and T-Systems Healthcare Competence Center Central and Eastern Europe. The developed experimental software engineering solution was embedded in hybrid cloud architecture after testing private cloud Infrastructure-as-a-Service and Public Cloud Software-as-a-Service technical solutions.

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This paper presents a pseudo-deterministic catchment runoff model based on the Richards equation model - the governing equation for subsurface flow. The subsurface flow in a catchment is described here by two-dimensional variably saturated flow (unsaturated and saturated). The governing equation is the Richards equation with a slight modification of the time derivative term, as considered e.g. by Neuman. The nonlinear nature of this problem appears in the unsaturated zone only, so it was possible to make use of adaptive domain decomposition algorithm. However delineating of the saturated zone boundary is a nonlinear computationally expensive issue. The simple one-dimensional Boussinesq equation was used here as a rough estimator of the saturated zone boundary. With this estimate the adaptive domain decomposition could always start with an optimal subdomain split, and thus it is now possible to avoid solving huge systems of linear equations in the initial iteration level.

With this measure it is possible to construct an efficient two-dimensional pseudodeterministic catchment runoff model. Finally, the model is tested against real data originating from the Modrava 2 experimental catchment, Czech Republic.

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The current work focuses on a Hungarian clothing manufacturer’s problem. First the industrial problem is presented; its corresponding critical pass method graph is depicted. To answer all emerging questions with respect to alternative possibilities, a large number of critical pass method problems have to be solved cumbersomely. Instead, first this graph is transformed into a process network. Alternatives specified by mainly financial necessities as well as human resource constraints can now be easily managed, namely where specific activities can be performed in different ways by various employee having different qualifications, requiring different durations and obviously respective costs can be considered within this model. These separate cases can commonly be handled within the resultant sole process network and the corresponding mathematical programming model.

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The resource management in a dynamic environment is a really complex problem. If semantic constraints are taken into account the complexity increases significantly. The problem definition of resource management using semantic constraints in the subject domain is demonstrated by means of an example of manufacturing scheduling. The application of multiagent approach is suggested and examined to solve the resource management problem. Experiments simulate two types of calculations of the resource allocation problem in manufacturing scheduling: the multi-agent approach and the sequential calculations. The experiments have demonstrated the effectiveness of multi-agent approach to solve the above defined problem.

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Authors: Mimoza Sylejmani, Gabriella Medvegy and Lulzim Beqiri

The paper deals with the analysis of the fortified dwellings - Kulla, which were constructed in Kosovo since XVIII–XIX century. As a case study, one took the Kulla, which were constructed in the Plain of Dukagjin. These types of dwellings were not constructed solely in Kosovo, but also in other countries of the region, that is: Northern Albania, Macedonia, and Montenegro. In Kosovo, the major parts of these buildings were constructed in the Plain of Dukagjin. Usually these buildings were constructed in two and three floors.

Characteristic feature of these buildings is the division of functions in vertical direction.

The research is based on the literature, analysis of the buildings, the research that was done up to now, including the interviewing of the persons-owners of the Kullas.

The aim was to get an understanding on the purpose of constructing the Kulla in vertical manner.

Kulla was analyzed in functional, architectural, constructive and condition aspect, which it offers to its inhabitants. There are a lot of factors that influenced on the construction of these buildings, one of them being the climate. Kosovo is characterized by a harsh climate during cold season of the year, which influenced on the relatively low height of the floors. Another feature is limited lighting in the ground floor, which increases steadily going further up to the last floor, as well as through the embrasures used for fire arms.

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A methodology is proposed to calculate statistical average and standard deviation of long time water quality parameter series along a river network. The method considers the water network as a graph consisting of straight sessions and junctions. With a Taylor-series approximation, statistical values of an arbitrary point of the network can be calculated from upstream ones without the need to calculate the single downstream values. According to preliminary results of the first calculations on a pilot area, mean value of the downstream biological oxygen demand and the so called ‘transfer coefficient’ can be approximated with a relative accuracy of 10%.

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From nanotechnology-based thermal insulation materials nano-ceramic thermal insulation coatings are generally considered to be the most critical because of contradictory technical data that could be founded in special literature. Complete agreement had not been already found about the mechanism how does their insulating effect take. In the Laboratory of Building Materials and Building Physics at Széchenyi István University (Győr, Hungary) several thermodynamic tests were made in order to find out thermodynamic process inside this material. Several building structures with different order of layers were tested with heat flow meter. Results showed that convective heat transfer coefficient cannot be taken account in usual way using this material as thermal insulation.

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E. coli is one of the major pathogenic bacteria that cause diarrhoea in human. Traditional fermented foods, e.g. Ogi, has been used indigenously to treat diarrhoea. This study was aimed at investigating the antagonistic activity of selected lactic acid bacteria (LAB) isolated from three varieties of ogi against multidrug resistant E. coli EKT004.

Antibiotic susceptibility of the tested E. coli EKT004 strain to ofloxacin, gentamycin, cefuroxime, ceftazidine, lincomycin, oxacillin, cloxacillin, cefotaxime, ciprofloxacin, and nitrofurantoin was tested by disc diffusion method. E. coli EKT004 was co-incubated in two different experiments with Weissella paramesenteroides, Lactobacillus plantarum, and L. fermentum that have been previously isolated from Ogi. An 8 h old E. coli was introduced into an overnight culture of LAB and a fresh E. coli was inoculated into overnight culture of LAB. Viable count of pathogen at 0 h and after 24 h co-incubation at 37 °C was observed.

The tested E. coli EKT004 was resistant to cefuroxime, ceftazidime, lincomycin, oxacillin, cloxacillin, and cefotaxime. The tested LAB isolates have a broad spectrum of activity against E. coli EKT004 used for the study with a decrease of 6–8 log of E. coli as compared with the control. These results indicate a direct effect of lactic acid bacterial strains on multidrug resistant E. coli strain.

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Authors: R. Magalhães, V. Ferreira, G. Biscottini, T.R.S. Brandão, G. Almeida and P. Teixeira

Contaminated food with Listeria monocytogenes is the predominant route of transmission of listeriosis to humans, a severe illness with a high mortality rate. Food processing environments can be colonized by persistent strains, repeatedly isolated for months or years. This study aimed to investigate the biofilm formation capacity of six strains of L. monocytogenes that persisted for long periods in two cheese processing plants in comparison to seven strains isolated sporadically from the same plants. Persistent strains produced more biofilm than non-persistent strains on stainless steel and silicon rubber surfaces; no significant differences were observed on polyvinyl chloride (PVC). In a polystyrene microtiter plate assay with crystal violet staining, no evidence was found that persistent strains have higher ability to form biofilm than non-persistent strains, and no correlation was identified between biofilm formation in the microtiter plate and on the three other surfaces tested.

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Authors: J. A. Pino, P. Winterhalter, R. Gök and J.C. González

The volatile compounds in commercial rums declared as aged 3, 7, 10, and 15 years were isolated by solvent extraction followed by solvent-assisted flavour evaporation and analysed by gas chromatography-olfactometry. According to the aroma extract dilution analysis, 19 potentially aroma-active compounds in the flavour dilution (FD) factor range of 8 to 1024 were found. Fifteen of them were present in at least one aged rum at FD factor≥128. Clear differences in the FD factors of these odourants between each of the aged rums suggested that they contributed to their unique sensory profiles.

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The inhibitory effects of phytic acid (PA) on the browning of fresh-cut chestnuts and the associated mechanisms of PA on polyphenol oxidase (PPO) and peroxidase (POD) activities were investigated. The enzymatic browning of chestnut surfaces and interiors was suppressed by soaking shelled and sliced chestnuts in a PA solution. The specific activities of PPO and POD extracted from chestnuts declined due to inhibition by PA. PA was determined to be a competitive inhibitor of both PPO and POD by Lineweaver-Burk plots. The binding modes of PA with PPO and POD were analysed by AutoDock 4.2.

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Authors: P. Olejníková, A. Kaszonyi, M. Šimkovič, B. Lakatoš, M. Kaliňák, M. Valachovičová and L. Birošová

The human endogenous intestinal microbiota is an essential “organ” in providing nourishment, regulating epithelial development, and instructing innate immunity. Even though lots of scientists have evaluated the content of gut microbiota from various points of view, we examined the content of intestinal microbes in the group of healthy middle aged volunteers (40–60) form Slovakia. We have compared faecal cultivable microbiota of vegetarians and omnivores. We have found that the composition of the human microbiota is fairly stable, and it seems that the major microbial groups on species level that dominate the human intestine are conserved in all individuals regardless of dietary habits. Beside the microbial content we have examined the faecal samples also for the presence of antimicrobial active compounds, potential mutagens, and faecal sterols.

Open access
Authors: B. Nagy, J. Soós, B. Horvath, M. Kállay, B. Nyúl-Pühra and D. Nyitrai-Sárdy

During the ageing in barrels, the contact with the fine lees triggers several processes in wine. Lees has a reductive effect by absorbing dissolved oxygen and reducing the amount, which will remain in the wine. At present, minimizing the addition of sulphur dioxide is the trend in all viticultural areas. In this study, the effect of various sulphur dioxide levels was monitored in presence of the lees to determine which dose is appropriate to provide the protection of susceptible white wine against oxidation.

Without SO2 protection, the rH and redox potential changed slightly, so the level of dissolved oxygen seemed to be controlled during the ageing period by the lees, though the antioxidant effect of lees in itself was not appropriate to protect the polyphenol content from chemical oxidation, which led to considerable browning. With the addition of a lower amount of SO2 — 40 mg l2, the lees is already able to protect the white wine samples in all aspects.

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In this research, simultaneous contribution of long-chain inulin (0–2.34%) and modified starch (0–0.58%) on the physical stability and rheological properties of doogh within 30 days of production was studied. Increased concentration of both hydrocolloids redounded to improvements in physical stability, apparent viscosity, flow behaviour, and viscoelastic properties compared to the control sample. Fitting the data to Herschel—Bulkley model showed a decrease in flow behaviour index, while consistency coefficient (k) increased. Furthermore, for samples containing inulin and starch, G′ was greater than G″, unlike control sample. Indeed, contribution of long-chain inulin at concentrations above 1.18% and modified starch at above 0.3% promote the formation of gel network structure. The expected viscosity increases in the continuous phase in the presence of starch, and also the interactions established between inulin and yoghurt casein aggregates seem to be responsible in the improvement observed in physical characteristics of the product. Among the concentrations studied here, two samples, containing 2% inulin and 0.5% modified starch and 1.18% inulin and 0.58% modified starch, respectively, were recognized as functional doogh samples presenting premier physicochemical and rheological properties.

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The aim of this research was to study the shelf-life of fresh-cut iceberg lettuce, testing a packaging film manufactured with and without addition of anti-UV compounds, and using two different protective atmospheres (N2/CO2 70/30% and Ar/CO2 80/20%). In order to simulate the most common retail storage conditions, the samples were stored at 6 °C under artificial light by using real supermarket refrigerated exposition stands. The data obtained showed that the use of an anti-UV film always causes a lower quality decay of the product; in any case, the best results were obtained when the anti-UV film was utilized in association with the packaging atmosphere consisting of Ar and CO2 (80/20%) gas mixture.

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Authors: J.M. Garcia, S. M. Castro, R. Casquete, J. Silva, R. Queirós, J.A. Saraiva and P. Teixeira

The effect of sequential treatments of pressure (50–150 MPa, 10 ºC, 5 min) and temperature (57 ºC, 15 min) on the survival and bacteriocin production of Pediococcus acidilactici HA-6111-2 cells in the exponential growth phase was assessed. The growth curves were fitted with the modified Gompertz model, and the estimated maximum specific growth rate was considered to be pressure dependent. A delay in the maximum value of bacteriocin production was registered for more severe pressure conditions, but it was found more notorious for pressure followed by temperature treatments. At lower pressure intensity treatment, regardless of the application order, there was an enhancement of bacteriocin production per cell when compared to the control while maintaining the maximum production value. Bacteriocin production after the treatments can be described by an exponential model.

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Enzyme-assisted extraction of carotenoids from tomato peels of the Bulgarian cultivar “Stela”, one of the most widely used cultivars by the canning industry, was examined in this study. The carotenoid content in raw tomato peels was established by HPLC analysis. A two-step protocol was followed: the tomato peels were first treated with enzymes and then extracted by the use of acetone as a solvent for 30 min at 20±1 °C and solid/liquid ratio of 1:30. The total carotenoid, lycopene, and β-carotene extraction yields were increased by the use of pectinase, cellulase, endo-xylanase, and proteinase enzymes in comparison with the non-enzyme-treated samples. The increase in the extraction yield was affected by the enzymes used, the enzyme concentration, the pretreatment time and temperature. Maximum total carotenoid (55.15 mg/100 g d.w.), β-carotene (35.85 mg/100 g d.w.), and lycopene (15.44 mg/100 g d.w.) extraction yields were obtained in peels pretreated with mixed cellulase (100 U g−1) and endo-xylanase (400 U g−1) for 4 h at 50 °C. Carotenoid recovery by mixed cellulolytic and hemi-cellulolytic enzyme pretreatment of tomato peels is a good approach, which can be used for waste utilization.

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Determination of consumers’ acceptance level of sushi meal among Czech respondents was the main aim. The survey included 1352 respondents that filled in a questionnaire on their demographic characteristics and food preferences regarding their acceptance of sushi meal. Additionally, 79 volunteers participated in sorting sushi among other 14 popular meals in the Czech Republic, according to their assumed situations. The results indicate that sushi is highly accepted among Czech consumers (more than 80% of respondents consume sushi) due to sensory characteristics and health benefit claims of sushi. The main barrier for sushi acceptance is sushi being a cold meal. The study emphasized that sushi price highly influences not only consumption frequency but also acceptance of sushi among respondents who declared not consuming this type of meal.

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Supercritical fluid extraction (SFE) was used for fractionation of grape seed to be applied in natural products of the food, cosmetic, or pharmaceutical industry. A two-step process was developed, consisting of conventional alcoholic extraction followed by SFE with carbon dioxide. The effects of pressure and concentration of co-solvent (ethanol) at constant temperature and solvent to feed-ratio were evaluated. The antioxidant activity of extracts and raffinates was measured with the DPPH* free radical scavenging assay. It was observed that supercritical carbon dioxide can be used in the described process for fractionation of an alcoholic grape seed extract to obtain a product with noticeably high antioxidant activity and a second one with no antioxidant activity or pro-oxidant activity.

Open access

Changes in the consumption habits of the population forces food industry to produce traditional products in modern ways, sometimes not taking into account the modified safety issues. The aim of this study has been to compare hazards and critical control points for traditional and industrial cremeschnitte production. The result shows that the traditional cremeschnitte production includes two additional critical control points, cooking and moulding of egg cream basis, which is essential for safety. In addition, the results of microbial analysis pointed out that the traditional cremeschnitte is safer than the industrial one produced from dried cream powder when comparing Escherichia coli, total aerobic count, and mould contamination (P<0.05). Moreover, our controlled contamination test with E. coli of raw material shows that the traditional cremeschnitte production process reduces microbiological hazard even in the worst-case scenario. All this indicates that traditional food safety practices are not granted and should not be neglected in new production technologies.

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Authors: L. Cuevas-Glory, M. Bringas-Lantigua, E. Sauri-Duch, O. Sosa-Moguel, J.A. Pino and H. Loría-Sunsa

In this study, production of sour orange juice powder utilizing a spray dryer was investigated. To prevent stickiness, maltodextrin DE 12 was used as a drying agent. While feed flow rate, feed temperature, and air flow rate were kept constant, inlet air temperature (120–160 °C) and maltodextrin content (maltodextrin dry solids/100 g feed mixture dry solids; 10–20%, w/w) were selected as the independent variables. Product properties investigated included ascorbic acid, volatile compounds, and moisture content. Ascorbic acid retention, volatiles retention, and moisture content were used in optimization of the process by response surface methodology. The optimum inlet air temperature and maltodextrin content were 156 °C and 20% w/w maltodextrin, respectively. This study revealed that by applying these optimal conditions, sour orange juice powder with 81.5% ascorbic acid retention, 5.5%, w/w moisture content, and 78% volatiles retention was produced.

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Authors: L. Darnay, A. Tóth, B. Salamon, K. Papik, G. Oros, G. Jónás, K. Horti, K. Koncz and L. Friedrich

The aim of this study was to show how microbial transglutaminase (mTG) can be used as an effective texture-modifier for two popular Hungarian products: Trappist cheese and frankfurter. In both cases we investigated how components of these products, milkfat in cheese and phosphate in frankfurter, can be substituted by mTG. Therefore, Trappist cheese samples were produced from cow milk of 2.8%, 3.5%, and 5% milk fat. The effect of ripening was evaluated with Texture Profile Analysis (TPA) and sensory evaluation (scoring test, 10 trained panellists). Springiness and cohesiveness values were significantly higher by enzyme-treated semi-hard cheese samples at lower milk fat levels. Sensory evaluation showed that the enzyme-treatment led to higher scores by cheese samples made from cow milk of 3.5% and 5% milk fat. Frankfurter was made with 0.1%, 0.3%, 0.5%, and 0.7% tetrasodium pyrophosphate, and partly enzyme-treated with 0.2% commercial mTG enzyme preparation. Our results showed that mTG is able to significantly improve hardness and crunchiness by frankfurters made with 0.1% phosphate addition. Our sensory evaluation suggests that mTG and phosphate should be applied in combination in order to have a final product with recognisably more homogeneous texture.

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Authors: Y. Zhang, W. Zheng, Q.C. Ying, L.-E. Shi, Z.-L. Zhang, M.-Z. Shi and Z.-X. Tang

The sub-acute toxicity of E. faecalis HZNU P2 was investigated in rats fed with different doses for 14 days. To evaluate the acute oral toxicity of E. faecalis HZNU P2, rats were fed with E. faecalis HZNU P2 at a high dose of 2×1011 CFU kg−1 for 10 days. Results showed that there were no abnormal clinical signs in any of the groups during the experiment. There were no significant differences in live weight gain among rats fed with E. faecalis HZNU P2, compared to those in control group. Macroscopic or microscopic examinations of organs revealed no abnormalities, indicating that E. faecalis HZNU P2 did not adversely affect the health of rats. Results of this study demonstrated that digestion of E. faecalis HZNU P2 in rats did not show any obvious signs of toxicity.

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The efficacy of 1-MCP on apricots at different treatment temperatures and days after harvest during 6 weeks of storage at 1 °C was investigated. On the 1st, 3rd, or 5th day after harvest, fruit were treated with 1-MCP at 1 °C for 24 hours. In order to evaluate the effect of temperature, apricots were exposed to 1-MCP at 1, 10, and 20 °C (on the 1st day after harvest). 1-MCP application reduced the ethylene and CO2 production and delayed softening. Fruit treated on the 1st day after harvest presented the highest firmness at the end of the experiment. No significant effect of treatment temperatures on apricot quality was observed. The time period between harvest and 1-MCP application could be delayed until the 5th day after harvest. Results showed that 1-MCP extended the storage life and maintained the overall quality of apricot during storage and shelf-life.

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This study was performed to evaluate the effect of lactococcin BZ and enterocin KP against Listeria monocytogenes ATCC 7644 in skim (0.1%), half (1.5%), and full fat (3.0%) UHT milks. The milk samples were inoculated with L. monocytogenes at the level of approximately 2.60, 4.76, and 6.45 log CFU ml−1, and then treated with various concentrations (400, 800, 1600, or 2500 AU ml−1) of lactococcin BZ, enterocin KP, or their combination (1:1). Lactococcin BZ at 400–2500 AU ml−1 level displayed strong antilisterial activity, and decreased the viable cell numbers of L. monocytogenes to an undetectable level in all types of milk samples during the entire storage periods at 4 °C or 20 °C. Enterocin KP also had a high antilisterial effect, but it decreased as both the fat content of milk and inoculation amount of L. monocytogenes increased.

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The paper describes efficient methods to post-process results from the finite element analysis. Amount of data produced by the complex analysis is enormous. However, computer performance and memory are limited and commonly-used software tools do not provide ways to post-process data easily. Therefore, some sort of simplification of data has to be used to lower memory consumption and accelerate data loading. This article describes a procedure that replaces discrete values with a set of continuous functions. Each approximation function can be represented by a small number of parameters that are able to describe the character of resulting data closely enough.

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Authors: L. Szalóki-Dorkó, A. Nagy, N. Adányi and R. Tömösközi-Farkas
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Part II of the study deals with changes of support structures interpreted among building constructions. We primarily link structural changes to the application of new materials and new approaches. Two areas are dealt with in this present study. One is the development and change of vaults, the other is changes of framework of building in case of applying new materials that are only partly suitable for taking bending and tensile stress.

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Authors: B. Csehi, E. Szerdahelyi, K. Pásztor-Huszár, B. Salamon, A. Tóth, I. Zeke, G. Jónás and L. Friedrich

In the experiments pork loin and beef sirloin were treated by pressures of 100 to 600 MPa by 100 MPa steps for 5 min. Colour changes of samples and the changes of proteins were investigated. The latter were examined with isoelectric focusing and SDS polyacrylamide gel electrophoresis. We found that myoglobin behaved completely differently in case of the two different species. Myoglobin has mostly lost its native state at 300 MPa pressure in case of pork, but the beef myoglobin could remain native even up to 500 MPa. The treatment at 300 MPa or higher pressure values caused almost complete aggregation and denaturation in case of pork and beef proteins. The results of SDS-PAGE and the colour measurement confirmed this finding.

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The issue of urban development requires strategic thinking. It includes self-sustainable mechanisms, strengthening self-organization and financing of the cities, collectively. Nowadays cities face challenges in all three domains that necessitate strategic thinking on the local, national and EU levels alike.

This strategic thinking has to answer the questions concerning how is it possible for a city to implement developments that might have-long term and sustainable results for the inhabitants. What is the underlying logic to define, plan, implement and sustain city policy objectives? The search for the answer provides multiple evaluation methods. One of these logical frameworks is measuring the success of cities in the context of development/s related to a specific event.

The success of cities is researched and measured with numerous tools and methods. Analyses in this field are becoming more common, not only on a yearly basis but even more often.

The City Success Index — interpreted and presented in the current study — puts larger emphasis on involving and evaluating the so-called human factors, meanwhile creates a logical frame, which - due to the portfolio-analysis method’s flexibility — is more ‘customizable’ for a city that would like to organize a world-class or international events with strong impact, and reveals the possible opportunities and threats. The methodology is able to contribute to strategy planning or for the evaluation of the event. The applied economic model as the frame of research in the approach is new, while the utilization of the result-zone developing might offer help in decision processes of several other public policy domains.

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In this study, the traffic flow of morning peak hour is analyzed in residential areas using dynamic traffic assignment method. A comprehensive analysis of the traffic assignment was performed in six different network topologies. The main goals were to compare different road networks and to identify significant similarities and differences of these patterns. By comparing results, a highly detailed picture of the differences crystallized between travel time, velocity and ratio of used routes.

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The European standards for asphalt mixture testing are mainly focused on empirical parameters of asphalt mixtures. On the other hand, functional parameters (e.g. fatigue, stiffness) of asphalt mixtures describe real behavior of the material in-situ. These parameters are used for design of road construction according to the Slovak design method where the elasticity modulus is used instead of the complex modulus. The problem is that no standard for elasticity modulus measurement exists in the collection of the European standards. In this study complex modulus measurement was performed according to the European standard, and for comparison elasticity modulus measurement was also done according to the Australian standard.

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Wind velocity profile varies in the boundary layer according to a complex pattern that depends hugely on the surface roughness and local Reynolds number. The presence of a macroscopic obstacle on the ground surface modifies considerably the flow characteristics of wind speed profile. In this study, the effect on wind speed resulting from local circulatory motion induced by the existence of an obstacle is analyzed in stationary conditions under the assumption of two-dimensional approximation of the problem. Computational fluid dynamics is used to solve the turbulent air flow equations that consist of Navier–Stokes equations coupled to a K-ε turbulence model. A bounded domain having a rectangular form was introduced in order to schematize the atmospheric region containing the obstacle and wind turbine. The boundary conditions at ground surface were fixed by applying a modified wall law. The other boundary conditions included a logarithmic velocity profile at the input, a uniform speed applied on the upper edge of the rectangular domain and a uniform pressure in the outlet area. To solve the obtained equations, Comsol Multiphysics software package was used. The obtained results have shown that the presence of an obstacle has a huge effect on the wind profile pattern and affects largely the extractable power from wind by the wind turbine system.

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The aim of the research is to reveal the most important influencing factors that lead to consumers’ acceptance of personalised nutrition based on genetic testing. A nationwide representative questionnaire-based consumer survey was carried out involving 500 people in Hungary in 2014. The results show that consumers are divided over the new technology. Only 27.0% of the respondents have a positive attitude toward the new possibility, and they would be glad to use this new service in order to stay healthy. The rate of those who would have a genetic test because they want to follow a diet tailored to their needs is very low (16.0%). Our result suggested that the most important factors in consumer preference on personalised nutrition are positive health message and perceived risk/benefits, gender, and educational level. The most important factors regarding the attitude toward genetic testing are easy usage, benefits, the agreement among experts, and educational level.

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Dietary fibres (DFs) are essential components of the balanced diet. Even though the adequate level of their consumption can be ensured from several natural (e.g. fruit, vegetables, legumes) and ‘artificial’ sources (e.g. functional foods), the consumed levels are below the recommendations. To analyse the Hungarian and Romanian consumers’ knowledge level, their perceptions of the health benefits associated with fibre, as well as the recognition of the potential information sources, a survey questionnaire was conducted with the total of 713 consumers. Results showed that the level of knowledge about DFs was not adequate. Internet was found to be widely used and identified as one of the most appropriate information sources to encourage the consumption of DF. It was a favourable result that three-quarter of the respondents was interested in the topic of healthy food consumption; however, just less than half of them took into consideration the label information during their shopping decisions. To increase the consumption of DF and to support the responsibility and conscious consumer decisions steps must to be done (e.g. education of children, pointing out of the sources). For this purpose, modern information technology and communication channels fitting to the consumers’ cultural and personal particularities can be utilized.

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The forty years of intensive mine dewatering in the Transdanubian Range contributed to getting high quality and large amount of data about the karstified aquifers, which could not be gained in any other way. In addition to providing the claimed depression to the safety mining under the original karst water level, the scientific investigation of the processes was emphasized. Although the mines were abandoned the data sets could be a great base of additional investigation about the karstified aquifers. This paper presents the evaluation of dewatering data as pumping test data by using many methods.

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The aim of the present study was to evaluate the effect of high hydrostatic pressure (HHP) processing (at 450 or 600 MPa for 300 s) on microbial quality as well as on organoleptic properties of fish salad with mayonnaise during 26 days of storage at 5 and 10 °C. The salad contained diced smoked trout fish, mayonnaise, and different kinds of spices. These freshly made salads usually have only a couple of days of shelf life. The HHP treatment basically did not affect the physical and organoleptic characteristics of the fish salad with mayonnaise. At both storage temperatures, the HHP treated samples showed enhanced safety and increased shelf-life up to 3 weeks.

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The role of light-emitting diode lamps and radio frequency lighting controls is to reduce the energy consumption. The increase of lighting network complexity determines the increase of EMC noise emission. Being familiar with measurement systems is important for making correct measurement and for understanding the results of the measurement. Correct interpretation of measurement results is the first step in choosing the best suppression method. The suppression method depends on the common mode and the differential mode of noise type and on the frequency of signal noise.

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This paper deals with the most recent technology in wireless communication which is massive multiple input multiple output system. The paper studies the performance of massive multiple input multiple output uplink system over Rayleigh fading channel. The performance is measured in terms of spectral and energy efficiency using three schemes of linear detection, maximum-ratio-combining, zero forcing receiver, and minimum mean-square error receiver. The simulation results show that the spectral and energy efficiency increases with increasing the number of base station antennas. Also, the spectral and energy efficiency with minimum mean-square error receiver is better than that withzero forcing receiver, and the latter is better than that with maximum-ratio-combining. Furthermore, the energy efficiency decreases with increasing the spectral efficiency.

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This research presents a field-circuit coupled parallel finite element model of a switched reluctance motor embedded in a simple closed loop control system. The parallel numerical model is based on the Schur-complement method coupled with an iterative solver. The used control system is the rotor position based control, which is applied to the FEM model. The results and parallel performance of the voltage driven finite element model are compared with the results from the current driven model. Moreover, the results of the start-up of the loaded motor show why the model accuracy is important in the control loop.

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Author: Péter Iványi
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Milk gangliosides have gained considerable attention because they participate in diverse biological processes, including neural development, pathogen binding, and activation of the immune system. The aim of this study was to determine the concentrations of total gangliosides in dairy products and to determine whether there is a significant difference in comparison to concentration of gangliosides in cow’s milk. The concentration of total gangliosides in dairy products was significantly higher than concentration in cow’s milk. The highest concentration of gangliosides was determined in yogurt with 3.2% of milk fat.

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Authors: I. Mohammadpour, R. Ahmadkhaniha, M. Zare Jeddi and N. Rastkari

The safe use of recycled paper and board material for food packaging applications is a major area of investigations. Therefore, the aim of current study was to evaluate the amount of heavy metals in recycled paper pastry packages and measurement of migration over the time into pastries.

In this study, the presence of heavy metals in common confectionery packaging and effects of storage time and kind of pastry on the migration are investigated.

The results of the study indicate that harmful metals such as Pb are detected at high concentrations in most of the recycled boxes that are used for pastry packaging, and heavy metals could migrate from the recycled packages into food during usage.

It seems that the procedure of preparing recycled paperboard for food packaging should be reconsidered.

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