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The objective of this study was to investigate the influence of irrigation on the composition and content of phenolic compounds and carotenoids in different tomato cultivars using HPLC/DAD-UV technique and reverse-phase (RP) chromatographic columns for analysis. Among phenols, the quercetin derivatives and hydroxycinnamic acids and their derivatives were the major compounds, while lycopene was the dominant carotenoid in the extract of tomato. It was found that the response of tomatos to shortage of water is affected by genetic factors and seasonal environmental variations. In general, 100% irrigation yielded tomatoes with the lowest level of carotenoids and polyphenols. In 2012, when the temperature and number of sunny hours were at record levels, the non-irrigated plants of cultivar Strombolino yielded tomatoes with significantly higher levels of carotenoids and phenols than that of the other cultivars.

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As a result of the fast innovation activity, the so called “many to many” communication channel has become one of the most important tools for the Hungarian food industry. The number of Internet users in Hungary was 6.5 million in 2011 that represents 65.4 percent of the total population. The Internet based social media provides a strong and active platform between food producers and consumers. The online platform gives up-to-date and precise information about food companies and food products to the consumers. The information flow is two-directional as food companies receive a precise overview on consumers, their habits and latent needs by using innovative market research methods. The aim of this paper is to present an example and to evaluate the customers’ socio-demographic profile and their preferences of a dominant food company and its product. We used data mining techniques to get more precise and the latest information about Hungarian food consumers. This survey supports more efficient marketing communication and strategies for the innovation of the food products.

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

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Yeasts of the Yarrowia clade frequently occur in meat and milk products. In many cases they cause spoilage due to their strong lipolytic and proteolytic activity, and their ability to produce brown pigments. Using conventional methods, some of these yeasts can be misidentified as Yarrowia lipolytica, but using molecular biological methods it can be stated that they are members of a complex group including several different species. The aims of this study were to find a proper method to collect Yarrowia strains from raw meat, and to assign them to groups based on their physiological and molecular characteristics, followed by sequence-based identification of the selected members of each group to determine the composition of the species. This study revealed three novel Yarrowia species. From 62 samples of different raw meats 291 yeast strains were isolated, from which 118 strains proved to be members of the Yarrowia group. They could be assigned to seven species. Four of them are described species, three of them are novel ones.

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The role of fats in food technology is mainly to develop the desired consistency. The simplest way to reach this goal is the blending of different fats. The aim of our work was to study the solidification and melting properties of blends of coconut oil and anhydrous milk fat. Pure fats and their 25–75%, 50–50%, and 75–25% blends were investigated. Melting profile and isotherm crystallization were measured by pNMR. Non-isotherm melting and solidification were detected by differential scanning calorimetry (DSC). Possible applications of the blends were established. Results show that AMF and coconut oil has limited miscibility, which is dependent on the temperature. Below 22 °C AMF is the softening component, above 22 °C the effect is inverse. Coconut oil accelerates solidification of AMF, however, basic crystal forms of AMF remained.

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Millet has attracted a great deal of interest due to its valuable agricultural, nutritional, and functional properties. In this study the aim was the investigation of millet usability in dry pasta products. Chemical, enzymological, and sensory parameters were measured and monitored in Triticum aestivum, Triticum durum, and millet containing pasta products during a 12-month-long storage period. According to our results, during the storage, millet had a strong effect on different parameters: because of increased acid value, the shelf life was reduced, and millet significantly influenced the pH value and the water soluble polyphenol content. The highest scores were measured in T. durum and T. durum-millet pasta samples in the sensory test, while the T. aestivum-millet mixture pasta got the lowest scores. Also in our experiment we tested how the drying temperature modifies polyphenol oxidase enzyme (PPO) activity right after drying and during storage. The samples containing millet flour had higher PPO activity in all cases after drying, while pasta made with T. durum had the lowest PPO activity. Our results showed that drying temperature has a significant impact on PPO activity.

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The food industry is in the crossfire of increasing pressure of competition, consumer demands, and growing importance of ecological sustainability considerations. Life cycle analysis is one of the most important methods for evaluation of environmental effects of food industrial technologies and packaging systems. During the last decades there have been an intense work to collect pieces of information on different environmental aspects of food packaging systems all over the world, but there is a considerable gap between the amount of knowledge and its practical application in decision making on the level of enterprises as well as in the process of determination of environmental protection fee. Application of modern, freely available software frameworks for life cycle analysis offers a favourable possibility for integration of environmental information into managerial and governmental decision making processes. Based on case studies, the article demonstrates the possibilities of utilisation of cumulative environmental burden indicators as well as expert decision-support systems for optimisation of product-portfolio, based on environmental considerations.

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Postharvest quality changes of two pear and five sweet pepper varieties during cold storage (2±1 °C and 10±1 °C, respectively) and shelf-life (22±2 °C and 20±1 °C, respectively) by non-destructive optical methods (laser backscattering imaging, chlorophyll fluorescence analysis, surface colour measurement) and texture analysis methods (acoustic impulse-response technique, impact method) were determined and monitored. The rate of the change of ‘Conference’ pears’ Fv/Fm chlorophyll fluorescence parameter was lower than for ‘Bosc kobak’, referring to the cultivar characteristic and photosynthetically active chlorophyll content related maturity and colour change. Acoustic and impact stiffness decreased during shelf-life, referring clearly to temperature related textural change. Taking into account the seven different measuring wavelengths (650–1064 nm), laser scattering parameters showed significant and cultivar dependent changes versus time during cold storage and shelf-life. The used non-destructive methods were found to be suitable for objective sweet pepper quality determination. Cold storage combined shelf-life resulted in a relatively longer shelf-life, with a lower intensity and rate of quality decrease in time, based upon mass loss, stiffness, surface colour, and chlorophyll fluorescence changes. ‘Gigant’, ‘Carma’, and ‘Kárpia’ cultivars were found to be favourable, but ‘Kais’ and ‘Kun’ hot pepper samples were really sensitive to quality degradation.

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In a period of economic crisis, there is a constantly increasing need to have a general picture on the place and role of different branches in fabrics of modern, open national economies. Based on Leontief’s input-output model, using the unified, structural database of OECD, the article analyses the economic role of the food industry in national economies of OECD member states as well as in economic structure of some important emerging markets by approach of network analysis. Applying this unique combination of a comprehensive database and network analysis methods, it is proven that the centrality of the food industry, determined on the basis of these indicators, is much higher than the average of other sectors of the national economies. This fact can be explained by the specific “bridge” role of the food industry between the different sectors of national economy. Results have proven the importance of the food industry and highlight the necessity of revision of governmental resource-allocation principles for R+D and industrial policy in member-states of the European Union.

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An appropriate rheological model can be used in production of good quality gum candy required by consumers. For this purpose Creep-Recovery Test (CRT) curves were recorded with a Stable Micro System TA.XT-2 precision texture analyser with 75 mm diameter cylinder probe on gum candies purchased from the local market. The deformation speed was 0.2 mm s−1, the creeping- and recovering time was 60 s, while the loading force was set to 1 N, 2 N, 5 N, 7 N, and 10 N. The two-element Kelvin-Voigt-model, a three-element model, and the four-element Burgers-model were fitted on the recorded creep data, and then the parameters of the models were evaluated. The best fitting from the used models was given by the Burgers model.

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Authors: G. Rácz, M. Alam, Ch. Arekatte, K. Albert, N. Papp, É. Stefanovits-Bányai, P. Russo, M. DiMatteo and Gy. Vatai

Different osmotic agents (OA), such as potassium acetate (CH3COOK), potassium carbonate (K2CO3) and ammonium nitrate (NH4NO3), have been examined as alternatives to the traditionally used calcium chloride (CaCl2) for osmotic distillation concentrating of clarified and pre-concentrated sour cherry (Prunus cerasus L.) juice. Comparison of the process performances based on the permeate fluxes has been carried out. Regarding the permeate flux results, simplified estimation of the overall mass transfer coefficient of the most effective osmotic agent and the reference (CaCl2) solution has been also performed. Furthermore, analytical methods such as total antioxidant activity (TAA) and total polyphenolic content (TPC) using spectrophotometric assays have been also carried out to evaluate the effect of the osmotic distillation on the valuable compounds content of concentrated sour cherry juice. CH3COOK was found to be the most effective, resulted more than 25% higher permeate flux during the sour cherry juice concentration. K2CO3 and NH4NO3 were less effective. The simplified mass transfer estimation showed that the CH3COOK is more effective only at near saturated concentrations compared to the CaCl2. Regarding the TAA and TPC contents, a significant loss was found in case of all OAs during the concentration procedures.

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Authors: L. Darnay, A. Dankovics, B. Molnár, L. Friedrich, Gy. Kenesei and Cs. Balla

Several scientific papers suggest that microbial transglutaminase (mTG) is capable of reducing the salt content of cured and/or heat-treated meat products (ham, frankfurters, meat ball). These scientific results are not widely known in Hungary, and as a result of this, only little experience was gathered in our meat industry. According to this lack of knowledge, our aim was to lower the curing salt to a still microbiological safe level using mTG by frankfurters, one of the most well-known heat treated meat products in Hungary. The observed technofunctional properties suggest to use mTG enzyme preparation at 0.5% concentration. This enzyme dosage can reduce the average 1.8% salt content to 1.6% and it also may contribute to extended shelf life of popular frankfurters. Our sensorial analysis revealed that the panellists have not found a loss in quality between 1.4% and 1.6% salt.

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Membrane emulsification (ME) is a relatively new technique for the highly controlled production of particulates, which helps to obtain a narrower distribution compared to other emulsification techniques such as homogenizers or ultrasound. Benefits of membrane emulsification for food applications include the low shear properties and the uniform size distribution. In this process, the dispersed phase (oil) is pressed through the pores of a microporous membrane directly into the continuous phase (water) flowing tangentially to the membrane surface. The purpose of the emulsification experimentations was to find and model operating conditions of the operation. In laboratory experiments from conventional, commercial grade sunflower oil (dispersed phase) and from distilled water (solid phase), emulsions were prepared. The ceramic tube membrane with nominal pore size of 1.4 μm was used in the experiments (ZrO2). In order to increase the shear-stress near the membrane wall (influence the characteristics of the flow regime of the continuous phase), a kind of self-fabricated helical-shaped-ribbon reducer was installed inside the tube membrane.

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Authors: E. Várvölgyi, T. Werum, L. Dénes, J. Soós, G. Szabó, J. Felföldi, G. Esper and Z. Kovács

Time consuming and expensive methods have been applied for detection of coffee adulteration based on the literature. In the present work, an optical method (vision system) and the application of an electronic tongue is proposed to reveal the addition of barley in different proportion to coffee in ground and brewed forms. In a range of 1 to 80% (w/w) Robusta coffee was blended with roasted barley. Principal Component Analysis (PCA) accomplished on vision system image data showed a good discrimination of the adulterated samples. The results of Polar Qualification System (PQS) data reduction method revealed even small differences in the right barley content order by point method approach. With Partial Least Squares (PLS) regression the amount of barley in Robusta was predicted with high R2 (0.996) and relatively low RMSEP (∼2%) values in case of vision system data processing. Considering electronic tongue measurements, PCA results showed a good discrimination of samples with higher barley concentration. Misclassification was found in the low concentrated area by Lienar Discriminant Analgsis (LDA). To obtain an accurate model for barley content prediction in coffee, the most sensitive sensor signals were used to apply PLS regression successfully (R2=0.97, RMSEP=3.99% (w/w)).

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Authors: Zs. Kiss, Sz. Kertész, C. Hodúr, G. Keszthelyi-Szabó and Zs. László

Nowadays, the membrane filtration technique is a commonly used method for the separation of whey. The most significant limitation of membrane applications is fouling, which causes flux decline. During this work, regenerated cellulose membranes covered by TiO2-nanoparticles were investigated and applied to the separation of whey solution. Experiments were carried out in a dead-end ultrafiltration cell, and the changes in filtration parameters and the photocatalytic effects of the UV irradiated TiO2 modified membrane surface on the membrane fouling were examined. Our results showed that the water flux decreased with increasing TiO2 layer thickness, but the retention of turbidity and of COD increased. After separation, the membrane surface was cleaned by UV irradiation by means of photocatalytic oxidation. It was found that the original flux was recoverable, while the retention of the membrane decreased after cleaning.

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Authors: F.J. Vazquez-Armenta, J.F. Ayala-Zavala, G.I. Olivas, F.J. Molina-Corral and B.A. Silva-Espinoza

This study evaluated the effect of onion essential oil (OEO) (0, 0.5, 2.5, and 5 mg ml−1) on microbial growth, browning decay, and sensorial appealing of cut potatoes stored for 15 days at 4 °C. Dipropyl disulphide and dipropyl trisulphide were the main constituents identified in OEO, and its application at a dose of 0.5 mg mlt-1 was the most effective to prevent browning (38.5% inhibition respect to control) during storage, inhibiting PPO activity (39% respect to control) after the treatment. The higher the added OEO concentration the lower microbial growth of the treated product was, achieving a reduction of 1.27 log CFU g−1 for the 5 mg ml−1 treatment. The odour and flavour appealing of cut potatoes were well received by the panelists after 10 days of storage. Therefore, the use of OEO in cut potatoes has a potential as antimicrobial and antibrowning agent.

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Antioxidant activity was studied for hydrolysates obtained from cowpea protein isolate by enzymatic hydrolysis using pepsin. Effects of 3 hydrolysis parameters: pH, temperature, and time were analysed using response surface methodology. A second-order polynomial model was used for predicting antioxidant activity of the hydrolysates. This model was adequate to fit experimental data and explained more than 85% of the variation. Interaction between pH and temperature was the major effect affecting antioxidant activity. Optimum antioxidant activity was observed after hydrolysis for 176 min, at pH 2.15, and temperature 38.2 °C. Under these conditions, the predicted antioxidant activity (22.69%) was in agreement with the experimental one. Degree of hydrolysis of the hydrolysate under optimum conditions was 25.70%, and the electrophoretic profile revealed the cleavage of several protein bands present in the isolate.

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Changes in microbial population, pH, sugar, organic acid, anthocyanins, total soluble phenolics, and anti-glucosidase contents were measured during fermentation of mulberry juice at 30 °C by probiotic Leuconostoc mesenteroides showing rapid growth after an approximately 1-day lag phase and reaching a maximum of 8.6 log CFU ml−1 after 4 d. During the rapid growth phase, the main mulberry juice sugars, glucose and fructose, were largely consumed, and the acidic metabolites, lactic acid and acetic acid, were produced accordingly. A slow decrease in the concentration of the main organic acid, citric acid, was also observed during fermentation. After 4 d fermentation, anthocyanin content showed a 44.4% reduction, but the total amount of soluble phenolics and α-glucosidase inhibitory activity showed no significant changes (P>0.05). This suggests that L. mesenteroides fermentation of mulberry juice is a good strategy to enhance its probiotic value and to decrease the sugar content without changing the anti-glucosidase activity, which is required to reduce postprandial rise in blood glucose.

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Authors: R. Tömösközi-Farkas, Zs. Polgár, M. Nagy-Gasztonyi, V. Horváth, T. Renkecz, K. Simon, F. Boross, Z. Fabulya and H. Daood

Anti-nutritive components in multi resistant potato cultivars were investigated in relation to conventional and organic farming for three years. Glycoalkaloids, nitrate, nitrite, asparagine, and glutamine contents of tubers were examined. Farming technology was found not to have an effect on the level of glycoalkaloids, which was influenced mostly by the genotype and season. Nitrogen fertilisation caused significant increase in nitrate, asparagine, and glutamine contents as compared to organic farming. Nitrite content was found to be more independent of farming technologies than nitrate. Tubers of cultivar Rioja had the lowest nitrate content irrespective of season or technology. In conclusion, the absolute amount and changes of different anti-nutritive components of potato tubers were influenced differently by the technology, genotype, and season in a complex manner. Organic farming had no effect on the glycoalkaloid content, but the nitrate levels had a tendency to be lower compared to conventional farming. This can be seen as a positive effect of organic farming.

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Palm fat is one of the most commonly used fats in food industry. The main role of palm fat is to develop the desired texture of food products. Fat blends were developed to find the most appropriate mixture fitting the technological needs. In our work palm mid fraction (PMF) was mixed with anhydrous milk fat (AMF), goose fat (G), and lard (L) in a 1:1 ratio. Anhydrous milk fat represents fat consisting of a wide range of fatty acids. Goose fat is a soft, easily melting fat, and lard is characterized as animal fat with wide melting temperature interval. The measurements aimed to establish the miscibility of the fats and the effect of animal fats on the melting-solidification profile of palm mid fraction. SFC vs temperature curves, Differential Scanning Calorimetry (DSC) melting thermograms describe the melting profile of the samples. Isotherm crystallization by SFC vs time curves and DSC cooling thermograms were measured to characterize the solidification of pure fats and the blends. Since the SFC curves did not show crosspoints we concluded that fats blended in a 1:1 ratio were miscible. Anhydrous milk fat strongly modified the properties of palm mid fraction, the blend became similar to anhydrous milk fat. Goose fat had no strong modification effect on palm mid fraction and could be considered as a softening agent. The effect of lard was complex: melting and solidification behaviour of the blend differed from the characteristics of both parent fats.

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Authors: O. Erdősi, K. Szakmár, O. Reichart, Zs. Szili, N. László, Z. Balogh, P. Székely Körmöczy and P. Laczay

The classical ISO (2002) standard as reference method and the combination of redox potential measurement with real-time PCR technique were applied to detect Salmonella in milk, egg, broiler meat, and artificially contaminated egg samples. Food samples of 25 g were homogenized in 225 ml of RVS broth to prepare the basic suspension of the comparative tests. In the combined method the redox potential measurement technique serves as the selective enrichment system of the real-time PCR equipment. The reliable screening of Salmonella-free, negative samples by the redox potential measurement technique needed only 24 h. These negative samples determined by the PCR and the classical standard method in all cases proved to be negative as well. In case of positive redox result the Salmonella from the enriched suspension of the redox test-cell was identified by real-time PCR in 3 hours, instead of the conventional biochemical identification. Comparing our protocol to the ISO (2002) standard method, the total detection time of Salmonella presence/absence was less than 24 h contrary to the 114 h of the conventional method.

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Authors: J. Tarek-Tilistyák, M. Juhász-Román, J. Jekő and E. Máthé

We evaluated the microbiological safety, the short-term storability, and the macronutrients of oil seed cake (OSC) obtained from walnut (WnC), linseed (LC), and sunflower seed with hull (SC). The OSCs had 3.6–5.8% moisture content, 0.50–0.60 water activity (aw), 29.9–39.4% protein, 15.5–23.6% fat, and 36.6–48.0% dietary fibre content. The grinded OSCs could be stored in opaque plastic bags for 4 months at temperatures of 4 °C, 14 °C, and 25 °C. Total colony count of mesophilic microorganisms depending on oxygen demand and spore-forming ability, and faecal indicator microorganisms were determined during a 4-month storage term at 4 °C, 14 °C, and 25 °C using traditional culturing methods. The OSCs were free from sulphite-reducing Clostridia and coliforms, including Escherichia coli. Data were analyzed statistically by multifactor analysis of variance. Ascending order of the average contamination of the three products (log10 CFU g−1) was aerobic sporogenic bacteria (2.39), fungal count (2.51), total aerobic microbe count (3.00), anerobic sporogenic bacteria (3.75), and total anaerobic microbe count (4.23). As for the average microbial count, WnC was the least (2.73 log10 CFU g−1) and LC was the highest (3.53 log10 CFU g−1) contaminated material. Regarding the variation of microbial contamination during storage, temperature was indifferent (P=0.191), while storage time (P=0.0033) and the product type were influential (P=0.000).

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Millet (Panicum miliaceum L.) is more resistant to climatic and soil conditions but the yields are lower than in wheat (Triticum aestivum L.), therefore its cultivation was given up for decades in Hungary. Millet is a suitable raw material for the production of pasta products without using eggs and it has other advantageous physiological effects, therefore its cultivation in Hungary is expected again. Millet is a gluten free cereal so it is not able to create viscoelastic protein network. During the biochemical studies the activity of enzymes (peroxidase, polyphenol oxidase) influencing the colour of the flour, flour mixtures (T. aestivum L., Triticum durum L., P. miliaceum L.), and pasta products were examined. Oxidoreductases in wheat flour have always been of interest to cereal chemists. The effects of peroxidase (EC 1.11.1.7) (POX) are much less thoroughly documented, although they are reported to have a relatively high level of activity in different flours. These days there are also insufficient research data on how the millet in dry pasta modifies the enzyme activity and the storage stability and shelf life of dry pasta products.

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In the junction capacity calculation methods the passenger car unit has a very important effect, because heavy vehicle traffic flow can only be counted with passenger car unit. Since not the proper passenger car unit values are used in the current practice, the results of junction capacity calculations cannot be regarded as correct, either. This research is focused on finding an answer as to whether the results are more precise if models with three junctions are examined rather than models with one junction.

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There was an architectural competition a few years ago in Kecskemét, which topic was the architectural renewal of the main square of the town and its surrounding area. The purpose of the competition was to explore the development opportunities of town center. The article presents the planning issues of this complex urban development through the award-winning plan of the A+ ‘Építész Stúdió’.

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Road traffic calming measures have been gradually spreading in cities since the 1960s. Therefore — in line with a sustainable transport planning approach — the revision and redistribution of urban transport and public surfaces have also come into the spotlight. In this context several traffic calming methods and techniques have evolved from point-based to areawide interventions. Their positive effects on traffic safety and the environment are indisputable. However, there are serious requirements concerning the application of these instruments, which need to be taken into account to prevent or minimize undesirable side-effects. Despite technical aspects and conditions that are well-known from the international literature, strategic aspects (economic effects and system-level prerequisites of traffic calming) are relatively ambiguous. The aim of this paper is to review the possible measures of road traffic calming, to demonstrate the effect-mechanism and to explore the way towards a consistent policy assessment framework, which can provide information on the strategic requirements of application.

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Authors: Julia Cigasova, Nadezda Stevulova, Ivana Schwarzova and Jozef Junak

Nowadays, the use of natural fibers as reinforcements for composite is attractive. Plant fibers from hemp, jute, sisal and others are used for the purposes of the construction. In this paper the attention is given to the preparation of composites based on hemp hurds. Hemp hurds is obtained from hemp stem in the fibers processing. Lightweight composites based on alternative binder MgO-cement and unmodified and chemically modified hemp hurds as filler were prepared. Their water absorption behavior was observed in time dependence.

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Authors: Ildikó Buocz, Nikoletta Rozgonyi-Boissinot, Ákos Török and Péter Görög

This paper presents a brief summary of the main existing shear strength test methods on both intact and fractured rocks, such as the triaxial, half-half notched specimen and direct shear strength tests. A detailed description of how to carry out a direct shear strength test on rocks along discontinuities are provided, supported by test results. The analyses include the interpretation of the tests and the calculation of the maximal and residual shear strength, as well as their angle of friction and apparent cohesion. These parameters depend on the properties of the rock and the discontinuity, such as the joint surface roughness, the rock texture orientation, the filling material, the thickness of the discontinuities, the scale effect and the magnitude of the applied normal force during the test. Their effect is discussed.

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On self-explaining roads drivers automatically drive according to the expected behavior and speed. In order to create this type of roads, within a given road category the layout should be homogenous, whereas a remarkable difference should exist between road categories. Using a sample of 500 persons, the paper analyses, which road categories are identified and distinguished by road users.A picture sorting task was completed to find out how road users group 45 different road scenes, and how these groups correspond to the road categories according to current standards.In addition, an analysis of a questionnaire survey was used to determine how individual road scene images are grouped on the basis of chosen speeds, and how this grouping corresponds to road categories. For processing of speed data, cluster analysis was used.The result of both surveys show that road users can clearly distinguish only 4–5 road categories. The paper compares these results with the design guidelines of some countries.

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The magnitude of the impact of the incorrect setting of the starting azimuth on the gradients established by the Eötvös torsion balance was tested at two different kind of area. According to the results, gradients measured by the Eötvös torsion balance are extremely sensitive regarding the precise adjustment of the starting azimuth if the vectors of gradients are high. Furthermore, the worst deviances were experienced in the case of curvature gradients i.e. the most important gradients for geodetic use.

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In Hungary the two most important service areas in the business service centers are the information technologies and the finance. Nowadays there is more and more information technologies service centers that deliver services for internal or external corporate partners as an outsourcing or a shared service center. However it is a robust trend in the Hungarian information technologies sector in the last two decades that these companies employ the most newly graduates of higher education but there are very few information about these centers. For example not only the growing headcount is important but these service centers are typically affiliates of big global companies that use new information technologies solutions as well. This research tries to get an overall picture about the players of information technologies business service sector in Hungary. Due to a comprehensive questionnaire and the research is based on the answers of 27 information technologies service centers on its strategic and operational work.

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Authors: Štefan Tkáč, Lukáš Sečka and Zuzana Vranayová

The paper introduces the current stage of hydropower and hydro-potential in a European landlocked country — Slovak Republic and Asia-Pacific island country — Taiwan R.O.C. (Republic Of China). Published data are present results of ongoing, one-year bilateral project focused on mapping the current development of renewable resources with closer zoom at hydroenergy and its role in overall energy development in both case studies. Purpose of the practical action research was to collect data and update information about existing power stations for records, possible future development scenarios, alternative stand alone energy approach and bilateral cooperation in the field of sustainable energy.

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Authors: Jozef Oravec, Aneta Petriláková, Vladimír Zeleňák, Magdaléna Bálintová and Adriana Eštoková

Mesoporous silica SBA-15 without and with modification of surface by grafting with aminoalcoxysilanes is prepared is the experiment. The prepared samples are characterized by adsorption/desorption of nitrogen. Results confirms the prepared materials having a specific surface area up to 846m2/g, which are improved for the capture of metals by grafting with the amino group. The sorption of Cu2+ cations as well as SO4 2− anions from the acidic solution is investigated. The modified mesoporous silica is confirmed to have better sorption capacity than unmodified mesoporous silica.

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Finite element meshes are the basic data structures of engineering analyses and simulations. Unfortunately many different kinds of finite element mesh formats exist. These different formats can make it difficult to handle the meshes in several aspects, for example when the same simulation should be checked and validated by another program or to preserve these data for long term. For both cases the conversion of finite element meshes can be a solution, however there is another problem in this case, that the size of the meshes are constantly increasing and meshes with over a million elements are commonly used nowadays. This paper would like to discuss how these large meshes can be converted in a parallel fashion and it also presents how this method can be used in the preservation and storage of finite element meshes.

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Authors: Alex Szakál, Gerhard Krexner, Andreas Grill, György Káli, Márton Markó and László Cser

Hydrogen due to its high incoherent cross section is a good candidate both for internal source or internal detector nucleus for atomic-resolution holographic measurements. Metal-hydrides are promising materials for the technology of hydrogen storage and the understanding of their structure is crucial. In the present work the solution of problems appearing at preparation of samples for the investigation of YH and PdH systems with the composition of YHx x<0.2 and PdHy at y∼0.7 is described.

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Memristors are not market ready devices yet, however their future applications can be tested with electric circuit simulation software on application oriented models. This paper proposes a simulation model for memristors that will possibly used in electrical engineering. Especially the unwanted saturation effect of the devices resulted by the direct current component possibly superimposed to the alternating operational current is investigated in this paper through simulation sessions.

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The unique spatial system of the medieval parish church in Kassa (now Košice, in Slovakia) induced strong debates in the literature, and some scholars called the master behind it a bungler. The reconstruction of the church at the end of the 19th century changed the floor plan entirely, with the result of a more regular arrangement.Using the drawings about the state of the church the medieval system is reconstructable in 3D. With the help of this 3D-model a structural analysis is possible.According to the spatial analysis and the structural calculations, the former unique layout of the church was the result of conscious planning.

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Silting of water reservoirs by bottom sediments is one of the major problems of their service. Industrial wastes, geochemical structure and metals mining create a potential source of heavy metal pollution in the aquatic environment especially in sediment. Water reservoir Ruzin located in east Slovakia is one of the most contaminated sites by heavy metals originating from mining activity. The paper deals with the study of sediment quality from three different deep sampling sites from Ruzin reservoir by using of XRF, XRD analysis and the determination of the effect of pH on the redistribution of metals in sediment-water system.

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Authors: A. Kisbenedek, Sz. Szabo, E. Polyak, Z. Breitenbach, A. Bona, L. Mark and M. Figler

Oilseeds are very popular edibles that are often used to enhance the fibre content of baked goods, and specific types are used for preserving and seasoning. Polyphenol-related researches have been receiving growing attention in the last 20 years, especially the ones concentrating on stilbenoids. In previous studies, resveratrol concentrations have been determined from oilseeds such as peanut.The aim of our research was to define the composition of oilseeds with a focus on the bioactive compounds, more specifically the resveratrol.Research took place in 2010–2011 at the University of Pécs, Medical School, using non-random, convenience sampling. Oilseeds studied in the research were: sunflower seed, roasted peanut, un-roasted peanut, sesame seed, pumpkin seed, almond, linseed, bio white mustard seed, bio black mustard seed, mustard seed of foreign provenance, and wild black mustard seed. All of these oilseeds can be purchased from trade. Samples used in the research were obtained from the producers and collectors. High Performance Liquid Chromatography (HPLC) was used for the measurements.Summarising our results, it can be stated that each type of oilseed analysed in our research can be regarded as good sources of resveratrol. The highest level of resveratrol was detected in the sunflower seeds (0.00398±0.0001 mg g−1), almonds (0.00176±0.00021 mg g−1), roasted peanut (0.00206±0.00013 mg g−1), and wild black mustard seeds (0.0023±0.0007 mg g−1).

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Authors: Sz. Szabó, Zs. Németh, É. Polyák, I. Bátai, M. Kerényi and M. Figler

Sprouts contain minerals, vitamins, and other compounds, which may have antimicrobial activity. Antimicrobial compounds are released from homogenized sprouts and diffuse into the culture medium inhibiting the growth of pathogenic bacteria. These antibacterial compounds may influence the multiplication of contaminating pathogens. In this study the antimicrobial effects of 55 different homogenized sprouts were investigated with agar well diffusion method on human pathogenic bacteria. Homogenizates of different radish, early kohlrabi, and red cabbage sprouts caused inhibitory zone around the wells on the surface of inoculated agar plates. Mustard, zucchini, medical (German) chamomile, spicy fenugreek, and adzuki bean sprouts had antimicrobial effect only against a few human pathogenic bacteria. Twenty-nine other spicy and vegetable sprouts had no antibacterial activity against the investigated human pathogens. The results suggest that a few sprouts have antimicrobial properties, but different cultivars of the same species have different effects against different bacterial strains. The sprouts of radish cultivars contained the most effective antibacterial compounds.

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A selective synthetic solid minimal medium (BS agar) was developed to detect antimicrobial drug-residues in foodstuffs using Bacillus subtilis indicator culture. This medium contains an ammonium salt as nitrogen source and either glucose or sodium pyruvate as carbon sources.Its selectivity is based on the fact that Bacillus subtilis is still able to grow if the minimal medium consists of simple inorganic substances as nitrogen sources, and glucose or pyruvate as carbon supply. Using these new synthetic media for microbiological assays assessing certain antimicrobials, the diameter of the inhibition zones were 1.4–4 times wider than on the Mueller-Hinton agar.The advantages of the BS agars are their standard compositions, the absence of inhibitors, the reproducible quality and the low costs.

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Authors: I. Dalmadi and M. Tóth-Markus
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The investigations carried out so far on high pigment tomatoes are confined to their nutritional aspects only. We present the comparative results of the first study on the kinetics of changes in chemical and sensory quality attributes in puree prepared from two colour mutants [dark green (dg) and old gold crimson (og c)] and seven normal tomato genotypes during storage. Puree of mutant tomatoes BCT-115 and BCT-119, carrying dg and og c genes, showed the less significant changes in TSS (7.52 and 6.02 °Brix), acidity (3.16 and 3.05%), pH (4.04 and 4.03), total sugar (12.4 and 11.13%), ascorbic acid (20.74 and 19.69 mg/100 g), lycopene (7.78 and 542 mg/100 g), and β-carotene (3.08 and 2.26 mg/100 g) during two months storage at 25 °C. Nevertheless, puree prepared from Berika and BCT-115 (dg) had higher colour (7.63 and 7.13), taste (7.4 and 7.37) and flavour (7.3 and 7.37) sensory scores during two months of storage at 25°C. These results provide new data on the effect of genotypes on the stability of quality for storage of tomato puree and insist on the utilization of these genotypes for breeding new processing cultivars in the near future.

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Authors: M. Benhanifia, K. Shimomura, I. Tsuchiya, S. Inui, S. Kumazawa, W. Mohamed, L. Boukraa, M. Sakharkar and H. Benbarek

The chemical analysis and antibacterial activity of propolis collected from some parts of Western Algeria were investigated. The ethanolic extracts of propolis (EEP) were evaluated for further investigation. The major constituents in EEP were identified by high-performance liquid chromatography (HPLC) analysis. All EEP samples were active against Gram positive bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus), but no activity was found against Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli). The mean diameters of growth inhibition of the EEP ranged between 8.05 and 21.4 mm. The propolis extract obtained from Sidi bel Abbés (SFS-SBA) was more active than other samples as well as showed unique HPLC profile. These results support the idea that propolis can be a promising natural food preservative in food industry and alternative candidate for management of bacterial infections caused by drug-resistant microorganisms.

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In the study we aim to model the information search behaviour of Hungarian consumers committed to sustainable consumption through the practice of food purchasing. To reach our goal we examined the logic of Grunert-Wills information search model.In our research the information search behaviour of “Trend followers” was investigated. To reach the mentioned group, data collection was carried out by the method of quota sampling, where quotas were defined according to characteristics of value system based lifestyle segments discovered in a 2011 national representative research by us. Through the analysis one-variable statistics and contingency table analysis were carried out.Our results prove the followings: (i) the logic of Grunert-Wills model is suitable for describing the information search behaviour of conscious consumers. (ii) Lifestyle has a highlighted effect on information search behaviour.

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Clarithromycin is an antibiotic widely used for Helicobacter pylori (H. pylori) eradication and together with amoxicillin and proton pump inhibitors they constitute the first line triple treatment regimen against H. pylori. Diarrhoea is one of the major drawbacks during H. pylori eradication and is majorly attributed to clarithromycin, while Saccharomyces boulardii is a probiotic and is shown to be effective in the treatment of antibiotic associated diarrhoea. We aimed to evaluate the effect of clarithromycin on orocecal transit in rats and to identify whether the supplementation with S. boulardii has a role on orocecal transit index. Adult rats of both sexes were divided into two groups to determine immediate or chronic effects of S. boulardii and clarithromycin on orocecal transit. The first group was given single dose of the test drug, while the second group received the test drugs for one week through orogastric intubation. Both groups were randomly distributed into four subgroups; the placebo group (group A), the S. boulardii group (group B), the clarithromycin group (group C), and the co-administration that is clarithromycin plus S. boulardii group (group D). Rats were given 20 mg kg−1 clarithromycin and 500 mg kg−1 S. boulardii. We did not find any difference among the subgroups in group 1, where only single dose of the test drugs was administered. In chronic administration group, that is group 2, significant differences among the subgroups were observed (P=0.004). Post-hoc comparisons of orocecal transit index between group “2A and 2C” and “2C and 2D” were significantly different (P=0.013 and P=0.005, respectively). Our results show that long term clarithromycin administration leads to rapid orocecal transit index and S. boulardii supplementation to clarithromycin can abolish this adverse effect in rats. Those findings suggest the beneficial use of S. boulardii in H. pylori eradication regimens.

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Vitamin A overdose is a common occurrence due to food fortification and ingestion of vitamin A supplements. Vitamin A is a nutrient that possesses known and potential effects on general health and the immune response. This research work is an in vivo investigation of the effects of administration of vitamin A above dietary requirements on some organs involved in immunity, vitamin A storage, and metabolism in healthy male rats. A total of 60 young adult male Wistar rats were equally divided into three groups. Rats in the two test groups were orally administered with vitamin A at different concentrations (8000 and 15 000 IU kg−1 body weight) for 21 days, while the control rats did not receive any supplementation. Weekly body weights and weights of the liver, kidney, spleen, and thymus were measured. Histological evaluations were carried out on the liver, kidney, thymus, and Peyer’s patches. Findings show that vitamin A did not significantly affect body and organs’ weights, except for a significant decrease of spleen weights for both experimental groups. Vitamin A was found to lead to some changes in the histology of the tested organs. This is the first study of its kind and sets a base for future studies.

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This study was conducted to develop a low cost method to preserve papaya (Carica papaya L.) pulp at ambient temperature with a combination of treatments including acid, heat, and cinnamon oil. Papaya pulp processed without and with 200 ppm cinnamon essential oil at pH 5.1, 81 °C, 7 min (ST2 and ST3); pH 3.9, 69 °C, 13 min (ST4 and ST5); and pH 4.5, 75 °C, 15 min (ST6 and ST7) was stored for 8 weeks at ambient temperature (28±2 °C). The cinnamaldehyde content of the papaya pulp treated with cinnamon oil decreased significantly during storage. ST5 and ST7 retained significantly higher β-carotene contents and lightness values compared to ST4 and ST6 during storage. The results indicated that acidification of papaya pulp to pH 4.5 and pasteurization at 75 °C for 15 min with 200 ppm cinnamon oil can be applied to obtain safe and high quality product, which is stable for 8 weeks at ambient temperature.

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Wheat is the major staple food in most temperate countries, including Europe and North America. In addition to providing energy and protein it is a significant source of a number of essential or beneficial components, including B vitamins, minerals, and dietary fibre. Cereal fibre has established benefits in reducing the risk of several chronic diseases but the consumption of fibre is below the recommended daily intake in the typical “Western diet”. Improving the content and composition of wheat fibre is therefore an attractive strategy to improve the health of large populations at low cost. The major dietary fibre components of wheat grain are arabinoxylan and β-glucan. Both vary in their amount, composition, and properties in different grain fractions, with white flour being lower in total fibre than bran but having a higher proportion of soluble fibre. There is significant variation in the amounts and structures of arabinoxylan and β-glucan in bread wheat genotypes, including commercial cultivars from different regions of the world, old landraces and exotic lines. This variation is also highly heritable, which should allow plant breeders to develop improved cultivars. Gradients in fibre composition and content within the grain may also allow millers to produce specialist high fibre flours.

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Authors: K. Szentmihályi, M. Szilágyi, J. Balla, L. Ujhelyi and A. Blázovics

Magnesium participates in numerous enzymatic reactions in the human body and it has essential role in the maintenance of the antioxidant system. Since several magnesium compounds have been applied in the food and pharmaceutical industry, our purpose was to investigate the antioxidant/free radical scavenging activity of some magnesium compounds in vitro. The antioxidant/prooxidant effect of inorganic salts (e.g. MgCl2) and organic complexes (e.g. Mg-gluconate) was determined with chemiluminometric method (H2O2/•OH-microperoxidase-luminol) and heme mediated LDL oxidation (LDL-heme-H2O2 ) in vitro. It has been stated that the chemiluminescence method and LDL (low density lipoprotein) oxidation measurement is applicable in the presence of magnesium salts and complexes. Most of the compounds do not generate free radicals and the antioxidant/prooxidant effect depends on the quality of the ligand and the concentration. In the concentration range used, some representatives of the magnesium compounds (MgO, Mg-gluconate, Mg-polygalacturonate) investigated showed radical generating activity measured with chemiluminescence method, whereas the LDL oxidation has not been affected. Magnesium citrate and malate proved to be antioxidants measured with the chemiluminescence method and they slightly accelerate the LDL oxidation in the system and in the concentration applied. In vitro some of the ligands of magnesium compounds showed antioxidant activities.

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Saccharomyces cerevisiae MERIT.ferm was used as mono- and mixed-cultures with Williopsis saturnus var. mrakii NCYC500 in mango wine fermentation. A ratio of 1:1000 (Saccharomyces:Williopsis) was chosen for mixed-culture fermentation to enable longer persistence of the latter. The monoculture of S. cerevisiae and mixed-culture was able to ferment to dryness with 7.0% and 7.7% ethanol, respectively. The monoculture of W. mrakii produced 1.45% ethanol. The mango wines fermented by S. cerevisiae alone and the mixed-culture were more yeasty and winey, which reflected their higher amounts of fusel alcohols, ethyl esters and medium-chain fatty acids. The mango wine fermented by W. mrakii alone was much less alcoholic, but fruitier, sweeter, which corresponded to its higher levels of acetate esters.

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Initiated by the Association “Wine Route of Etyek Wine District”, the objectives of this study were to isolate and identify autochthonous yeast strains from local wines and to determine their oenologically important properties. The first aim of this work was to characterize the taxonomic and phenotypic diversity of the representative Saccharomyces yeast strains that dominate the spontaneous fermentations in this wine district. The results obtained by molecular ribotyping (ARDRA) revealed a strong dominance of S. cerevisiae, but S. bayanus var. uvarum was also present sporadically. Some of the natural isolates exhibited high volatile acid production or poor fermentation capacity, which imply a quality risk in spontaneous fermentations. Most of the isolates, however, displayed good oenological features during lab scale fermentations. As the second aim of this work, the most promising, selected strains were further tested for oenological properties in microvinification scale and, finally, in large scale fermentations. The analytical and sensory analysis proved that selected strains, including S. bayanus var. uvarum, can be used as local starter cultures, which may contribute to the typicality of the local wines in comparison with commercial starters.

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Physical properties of maize were evaluated as a function of moisture content. The obtained data provide help in the designing of post-harvest handling machinery. In the moisture range of 10–18% wet basis (w.b.), the length of the rewetted grain increased from 10.01 to 10.65 mm, width increased from 8.57 to 8.70 mm, thickness ranged from 4.63 to 4.97 mm, geometric mean diameter (GMD) increased from 7.34 to 7.67 mm, sphericity increased from 0.72 to 0.73, thousand kernel weight (TKW) increased from 258.1 to 287.9 g, bulk density decreased from 591.6 to 554.2 kg m−3, true density increased from 1194.9 to 1267.2 kg m−3, porosity increased from 52.61 to 56.27%, hardness decreased from 293.75 to 228.04 N, initial cracking force decreased from 190.11 to 137.35 N and area ranges from 55.09 to 36.58 Nmm. In the same moisture range the angle of repose varied from 23.36 to 28.55 for grain. Lightness (L) of grain ranges from 62.82 to 59.26, a value (red-green axis) ranges from 13.97 to 8.96, b value (yellow-blue axis) ranges from 31.05 to 26.19 and hue angle (z%) decreased from 14.59 to 14.06 with increase in moisture content of grain from 10 to 18% w.b.

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It is believed that lipids are the most important factor affecting nuts shelf-life. In the present study, an accelerated shelf-life testing by means of elevated temperatures 62, 72, and 82 °C was conducted to predict the oxidation stability of walnuts over a long-term storage. Peroxide value (PV) was employed to monitor the lipid oxidation progression in the walnuts. A range of 74.01–79.57 kJ mol−1 K−1 energy was required for formation of primary oxidation products. The reaction changes followed an apparent first-order kinetic. Formation of hydroperoxides in walnut kernels was found to be a temperature-dependent reaction with Q10 of 2.1. Walnut kernels were also kept in normal condition (temp: 20–30 °C; relative humidity (RH): 35–45%) for 12 months to validate the shelf-life estimation approach. The results showed that PV could provide a proper estimation for oxidative stability of the walnuts stored in ordinary condition.

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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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