The total concentrations of the Ʃ16 polycyclic aromatic hydrocarbons (PAHs) were examined in some samples of baked ready-to-eat foods (cake, sausage roll, meat pie, burger, and bread) with a view to provide information on the hazards associated with the consumption of these hawked street foods. The measurements were performed by using a gas chromatograph-mass spectrometer (GC-MS) after hexane/dichloromethane extraction and clean-up. The total concentrations of the PAHs in these samples of ready-to-eat baked foods ranged from 427.4 to 1224 μg kg–1, 289.9 to 853.7 μg kg–1, 574.4 to 2333 μg kg–1, 364.6 to 2906 μg kg–1, and 15.7 to 213.1 μg kg–1 for cake, sausage roll, meat pie, burger, and bread, respectively. The results indicated that these baked ready-to-eat foods were mainly contaminated with 2-, 3-, and 4-ring PAHs. The concentrations of benzo(a)pyrene were less than 0.1 μg kg–1 in nineteen out of the twenty samples examined.
Authors:J.C. Spada, L.D.F. Marczak, I.C. Tessaro and N.S.M. Cardozo
Power ultrasound has vast potential in the food industry; however, there are no works on its effects on desserts. Thus, the objectives of this study were to investigate the effect of ultrasound as a mixing or homogenization step or as a tool to modify the texture of the soy-based desserts without reformulating the product. Different properties of soybased desserts were evaluated and the behaviour of the samples during storage under refrigeration (60 days) was monitored. The samples were treated with an ultrasound probe for 1, 3, and 5 min. The treated samples showed lower mean particle size, lower consistency index, higher flow index, and clear difference in their microstructure. However, water holding capacity and particle size dispersion index values did not differ among untreated and treated soy based desserts for 1 and 3 minutes, and none of the treatments caused visible colour differences among the samples. Periodically, rheological properties, pH, soluble solids content, colour, particle size, and water holding capacity were determined. After 60 days, all evaluated properties differed significantly, except for the pH.
Authors:E. Šárka, P. Smrčková, J. Koláček, M. Sağlamtaş, D.A. Chena Aldao and V. Pour
The aim of the paper was to seek suitable conditions of extrusion cooking using a laboratory single-screw extruder to increase slowly digestible (SDS) and resistant starch (RS) content in extrudates saving sensory characteristics of the final product prepared from corn grits with added native wheat starch, distarch phosphates, or soluble fibre Nutriose (Roquette, France).
In addition to the composition of input mixtures, process parameters of a single-screw extruder, such as speed of screw and barrel temperatures, were changed. The highest expansion ratio (4.14) was found for temperatures 44 °C, 90 °C, 120 °C, and 140 °C, die diameter 3 mm, compression ratio 3:1, rotation speed 140 r.p.m., and dosing 15 r.p.m. The addition of native wheat starch to corn grits resulted in values of the expansion ratio ranging from 1.17–2.38.
A high concentration of RS — 2.4% per starch — was observed for a 20% ratio of Nutriose with a 10% addition of water. The addition of 20–50% of native wheat starch resulted in values ranging from 0.2–0.4% per starch. The highest SDS content (72.5% per starch) in extrudates was obtained for the mixture of corn grits, 20% cross-linked starch, and water (10% addition).
Lycopene content (LC) and soluble solid content (SSC) are important quality indicators for cherry tomatoes. This study attempted simultaneous analysis of inner quality of cherry tomato by Electronic nose (E-nose) using multivariate analysis. E-nose was used for data acquisition, the response signals were regressed by multiple linear regression (MLR) and partial least square regression (PLS) to build predictive models. The performances of the predictive models were tested according to root mean square and correlation coefficient (R2) in the training set and prediction set. The results showed that MLR models were superior to PLS model, with higher value of R2 and lower values of for RMSE firmness, pH, SSC, and LC. Together with MLR, E-nose could be used to obtain firmness, pH, soluble solid and lycopene contents in cherry tomatoes.
The objectives of this publication are to present a production technology which is a finishing production of conical worm using changing of centre distance between the worm and the grinding wheel and banking angle correction at the same time. We will determine the necessary optimum grinding wheel profiles for the manufacturing in light of the production tolerances. We will determine the function connections between the main production parameters.
Authors:K. Régaiszné Vajda, A.A. Halbritter, P. Szűcs, J. Szigeti and B. Ásványi
Sous-vide (French for ʽunder vacuum’) is a professional cooking method, by which, under oxygen-free conditions and precise temperature control, not only cooking but preservation is achieved. During the process the food matrix is vacuum-packed and undergoes a mild heat treatment, thus achieving an enhanced nutrition value and a better organoleptic character. Due to the mild heat treatment (55 to 90 °C), the high water activity, and the slight acidity of raw materials, the microbial quality assurance is a great challenge even for professionals. The heat treatment does not assure the inactivation of pathogen spores. In our experiments we used Clostridium perfringens representing the spore-forming pathogens, and Salmonella Enteritidis as a the food-borne infection bacterium. Effects of various temperatures were measured in normal and sous-vide type vacuum packaging. Higher thermal death rate in vacuum packaging was demonstrated for Salmonella Enteritidis and Clostridium perfringens.
Authors:A. Harasztos, G. Balázs, P.N. Csőke, S. D’Amico, R. Schönlechner and S. Tömösközi
The positive nutritional impact of dietary fibres (DF) gives growing interest to their role in the formation of wheat product quality. Although we are getting closer to characterize the effect of DF on the end use quality, the roles of individual components are not well described yet. Arabinoxylans (AX) are the main compounds of wheat DF, therefore getting more knowledge about its behaviour in wheat based food systems, like dough or end products, could be useful from both theoretical and practical points of view. The aim of this study was to investigate the impact of the AX content on wheat flour quality using a dough model system provided by blends of flour and AX isolate. Rapid Visco Analyser (RVA) and recently developed micro Zeleny test were used for characterization of mixtures.
We found that although Zeleny values are basically related to protein-dependent quality, the addition of AX isolate has major impact on the sedimentation volume of flour. In the RVA studies we demonstrated that AX has influence not only on the viscosity values but also on the rate of viscosity change. The effect of AX addition was compared to that of starch addition and was corrected by the rate of dilution. The model system and the experimental method applied here can be suitable to separate the individual effects of non-starchy carbohydrates.
Authors:O. Cetin, E.B. Bingol, E. Civan, S.I. Turgay and O. Ergun
The demand for ready-to-eat meat products has recently increased, and routine controls are inevitable to provide food safety. Therefore, a total of 250 fresh processed beef meat products collected from local markets and restaurants in the districts of Istanbul mostly with low purchasing power were investigated by histological and biomolecular methods. Chicken tissue was found in 62 (24.8%) of the analysed samples and horse tissue was found in 2 (0.8%) samples, while pork tissue was not detected. Additionally, foreign tissues were detected in 70 (28%) of 250 samples. PCR assays combined with histological examinations can be used as an important method in establishing food safety by determining the deliberate or accidental adulterations of meat products.
The aim of this study was to assess the impact of hanging position of hunted pheasant carcasses (secured by the head as compared to hanging position secured by the legs) on the biogenic amine concentration in the thigh and breast muscles. The carcasses of feathered game (Phasianus colchicus), left entirely untreated after hunting and placed in a storage space at a pre-set temperature of 7 °C for 21 days were used in the study. Samples of breast and thigh muscles were taken at regular weekly intervals. Measurement of biogenic amines (putrescine, cadaverine, tyramine, tryptamine, histamine, phenylethylamine) was based on high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. Higher biogenic amine concentrations were detected in the muscles (both breast and thigh) of pheasants hanging by their legs compared to pheasants hanging by their heads (no statistically significant difference in biogenic amine concentration between monitored groups was, however, established). Higher concentrations of biogenic amines were found in the thigh muscles compared to breast muscles in both monitored groups. The obtained results show, that hanging the carcasses of pheasants during storage by the head is more suitable method in term of biogenic amine concentration than storing carcasses hanging by the legs.
Non-linear finite element calculations are indispensable when important information of the material response under load of a rubber component is desired. Although the material characterization of a rubber component is a demanding engineering task, the changing contact range between the parts and the incompressibility behaviour of the rubber further increase the complexity of the investigations. In this paper the effects of the choice of the numerical material parameters (e.g. bulk modulus) are examined with regard to numerical stability, mesh density and calculation accuracy. As an example, a rubber spring is chosen where contact problem is also handled.
Authors:J. Belovai, R. Romvári, H. Fébel, M. Mézes, D. Bánáti and A. Szabó
Replacement of animal fat with plant oils is a very popular research field, due to the increasing prevalence of cardiovascular diseases in association with saturated fatty acid consumption. The aim of this study was to reduce amount of pig backfat in a meat product (Párizsi) and to partially replace it with soybean- (SBL) or sunflower lecithin (SFL). Between the samples difference was realized in fatty acid (FA) profile, mostly in total n6 FA content. The replacement also altered the colour compared to the control. The oxidative stability (MDA) analysis showed that SBL was more prone towards preparation technology (10 nmol MDA/g) than the Sfl(9 nmol MDA/g). The lecithin appeared as foreign taste based on the sensory test. The aromatic difference, as assessed with electronic nose, was clearly detectable between Sfland SBL. The increasing supplementation levels were also properly distinguished with discriminant analysis within the SBL and Sflseries. Summarized, Sflwas found to be a better antioxidant, but SBL improved the FA profile into a more favourable state. The lecithin-replacement made unlikeness in the taste compared to the control.
Authors:Sz. Bánvölgyi, T. Vatai, Zs. Molnár, I. Kiss, Ž. Knez, Gy. Vatai and M. Škerget
Two novel technologies were applied in order to investigate concentration and formulation of anthocyanins for potential use in food industry. Integrated membrane process technology was applied for concentrating elderberry juice. In the first step, the juice was clarified by microfiltration, followed by a pre-concentration step with reverse osmosis. Finally, the juice was concentrated to the end concentration of 56 °Brix by osmotic distillation. The elderberry juice concentrate was formulated in a powderous form by a high-pressure process — Particles from Gas Saturated Solution (PGSS™) — using supercritical CO2. The applied carrier material was palm fat. The products with different anthocyanin-carrier ratios were measured for their colour properties (lightness, hue angle, and saturation). Colour stability was monitored for prolonged storage at different conditions (light/dark and ambient temperature/ refrigerator). The obtained powderous anthocyanin-palm fat products showed good colour stability, which gives good bases for potential applications in the future.
Nowadays large transparent surfaces are widely used in office and public buildings. The positive effect of great views and natural light on people’s comfort is well known, but the high glazed ratio of building facades can lead to excessively high cooling energy demands. The heat load can be reduced by using glazing with high reflexion coating outwards and low emission coating inwards, triple panes and inert gas between the panes. Choosing proper thermal mass can further help in reducing the amplitude of the indoor operative temperature. In this paper the effects of solar factor of glazing, heat transfer coefficient of windows, windows area and thermal mass were analysed in an imaginary room with 3.0×4.0×2.8 m dimensions. As the results show the effect of the overall heat transfer coefficient is negligible. The effect of solar factor depends on the orientation. The expected differences between the amplitudes of the operative temperature are between 0.5 to 6 K for the analyzed room, depending on the thermal mass, orientation, solar factor and window area.
Authors:V. Kapcsándi, A.J. Kovács, M. Neményi and E. Lakatos
The aim of our experiments was to demonstrate the non-thermal effect of microwave treatment on Saccharomyces cerevisiae fermentation activity. A method was developed for studying the effects of various treatments in the course of must fermentation. The raw material (must) was treated in different ways: (i) heat transfer; (ii) microwave treatment; (iii) inoculation with yeast, and (iv) their combinations. The results of the treatments were compared with respect to alcohol concentration, sugar content, and acidity. The results proved that sugar content of the treated samples rapidly decreased compared to the control sample, and fermentation time was 40% shorter in the fastest case. These results can be explained by the yeast inoculation and microwave treatment. Due to non-thermal effects, fermentation capacity increased by about 30%, while the energy consumption decreased.
Authors:M. Gąsecka, M. Mleczek, M. Siwulski, P. Niedzielski and L. Kozak
The phenolic and flavonoid contents and composition and the antioxidant ability in Hericium erinaceus, Ganoderma lucidum, and Agrocybe aegerita under selenium (Se) addition to growth medium were studied. The contents of total Se in fruiting bodies of controls (0 mM of Se) were 4.58 (A. aegerita), 8.53 (G. lucidum), and 14.29 (H. erinaceus) mg kg–1 dry weight (DW), and was significantly increased by Se enrichment of substrate. The total phenolics in fruiting bodies of controls of H. erinaceus, G. lucidum, and A. aegerita were significantly lower (17.10, 28.11, and 16.05 mg of gallic acid equivalent (GAE)/g of extract, respectively) than for Se-rich mushrooms (26.29, 40.29, and 20.07 mg GAE/g of extract, respectively). Total flavonoid content for H. erinaceus, G. lucidum, and A. aegerita increased after Se supplementation from 368.6 to 445.6, 469.9 to 627.7, and 318.1 to 393.9 μg g–1 of extract, respectively. The results show that the mushrooms have superior antioxidant properties after Se addition, because the scavenging ability on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals was improved.
Authors:V. Tomović, B. Žlender, M. Jokanović, M. Tomović, B. Šojić, S. Škaljac, Ž. Kevrešan, T. Tasić, P. Ikonić and Đ. Okanović
Physical (pH and L*a*b* values) and chemical (moisture, protein, total fat, total ash, K, P, Na, Mg, Ca, Zn, Fe, Cu, and Mn) characteristics of offal consisting of the tongue, heart, lungs, liver, spleen, kidney, brain, and spinal cord of free-range reared Swallow-Belly Mangalica pigs were determined. Many significant differences were found among mean values of quality traits. However, except for a few cases, the determined offal quality traits were in the characteristic ranges reported in the literature. Lungs were high in pH24h (P<0.01) and L*a*b* values (P<0.01), as well as in moisture and Na concentration, and the lowest in K, Cu, and Mn. Tongue was high in total fat, and the lowest in pH24h, moisture (P<0.01), and total ash concentration. The highest levels of protein (P<0.01), Mg, Fe (P<0.05), Zn (P<0.01), and Mn (P<0.01) and the lowest of Na were found in liver. The darkest colour (lowest L* value), highest concentration of K, the lowest concentration of total fat and Ca were found in spleen. Finally, spinal cord was the highest in total ash (P<0.01), P (P<0.01), and Ca (P<0.05) and the lowest in protein, Mg (P<0.05), Fe, and Zn (P<0.01) concentration.
Authors:S. Muzaffar, K. Maqbool, I.A. Wani, F.A. Masoodi and M.M. Bhat
Studies were conducted to characterize the chestnut starch for physico-chemical properties. Chemical composition of chestnut starch showed low levels of protein and ash indicating purity of starch. The results revealed low water and oil absorption capacity of chestnut starch. Starch showed high swelling power and low solubility index. Swelling power and solubility index of chestnut starch increased with increase in temperature (50–90 °C). The results revealed high initial, peak, setback, breakdown, and final viscosity but low paste development temperature. Transmittance (%) of the starch gel was low and decreased with increasing storage period. The chestnut starch gel showed increase in % water release (syneresis) with increase in time of storage but was less susceptible to repeated cycles of freezing and thawing. Starch was also characterized for granule morphology. Starch granules were of round and oval shapes, some granules showed irregular shape.
Authors:E. Polonkai, E. Gyimesi, I. Kovács, A. Csillag, Gy. Balla, É. Rajnavölgyi, A. Bácsi and S. Sipka
In this study, we examined the relationship between levels of lactoferrin (LF) and IL-17 in human serum and breast milk and the development of allergy in children. LF and IL-17 levels were determined by ELISA in healthy (n=19) and allergic mothers (n=21) on the 5th day after delivery. Two years later, information on breastfeeding and allergic outcomes was collected by questionnaires from parents of both groups and district child care nurses. Significantly higher concentrations of LF were found in the breast milk of allergic mothers compared to the healthy controls. At 2 years of age, only those three infants became allergic from the atopic group in whose starting breast milk samples a very high LF level (306 μg mg–1 protein) or simultaneously elevated concentrations of LF and IL-17 were measured. These findings indicate that the very early measurement of LF and IL-17 levels in the breast milk of allergic mothers may help to predict the allergy development in their infants.
Authors:W. Wiczkowski, D. Szawara-Nowak, T. Sawicki, J. Mitrus, Z. Kasprzykowski and M. Horbowicz
The aim of the study was to analyse the content of phenolic acids, total phenolic compounds, proanthocyanidins, and antioxidant capacity in cotyledons and hypocotyl of five cultivars of common buckwheat (Fagopyrum esculentum Moench) sprout. This study presents the first broad profile of phenolic acids occurring in buckwheat microgreen seedlings. In the hypocotyl and cotyledons trans-cinnamic acid and its derivatives: o-, m-, and p-coumaric acids (2-, 3-, and 4-hydroxycinnamic), synapic acid (4-hydroxy-3,5-dimethoxycinnamic), caffeic acid (3,4-dihydroxycinnamic), and two isomers of ferulic acid (4-hydroxy-3-methoxycinnamic and 3-hydroxy-4-methoxycinnamic) have been identified. Among the benzoic acid derivatives hydroxybenzoic, protocatechuic (3,4-dihydroxybenzoic), gallic (3,4,5-dihydroxybenzoic) and syringic (4-hydroxy-3,5-dimethoxybenzoic) were found in the organs. In addition to those mentioned, the organs of buckwheat sprouts contain chlorogenic acid as well. The contents of all analysed phenolics were substantially higher in the cotyledons than in the hypocotyl of buckwheat sprouts, except for chlorogenic and caffeic acids. Trans-cinnamic acid was the major phenolic acid in both organs. In the cotyledons, a significant, positive linear correlation between the TEAC, ORAC, PLC-ACW values and content of total phenolic compounds, and also between DPPH and total phenolic acids were found. In the hypocotyl correlations between the DPPH, TEAC, and ORAC and proanthocyanidins content, between TEAC and total phenolic compounds, and between total phenolic acids and PCL-ACW were found.
Authors:R. Tabaraki, E. Heidarizadi, N. Sadeghinezhad, S. Salimpour and Z. Yosefi
Fruit processing industries produce by-products that are good sources of natural antioxidants. These residuals are non-toxic and available in large quantities. A central composite design (CCD) and response surface methodology (RSM) were used to optimize experimental conditions. The processing variables were solvent type, solvent to solid ratio, ethanol concentration, temperature, and time. The responses were total phenolic content (TPC), scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, and yield. The optimal conditions were 70% ethanol— water mixture as a food grade solvent, temperature of 35 °C and extraction time 60 min for obtaining extracts with maximum of total phenolic content. Predicted values for total phenolic content in pear, apricot, and peach were 24.7, 19.3, and 10.4 mg gallic acid equivalents per 100 g fruit residual, respectively.
Authors:L. Varga, R. Engel, K. Szabó, L. Abrankó, B. Gosztola, É. Zámboriné Németh and S. Sárosi
Ground ivy (Glechoma hederacea L.) is one of the prosperous plants for the food-industry as natural antioxidant. This fact led us to examine the chemical diversity of six ground ivy populations situated in different natural habitats and to analyse the effect of the harvesting time. Total phenolic content, chlorogenic acid, and rutin content, as well as the antioxidant capacity showed significant differences due to the harvest time. The highest total phenol content (115 mg g–1 GAE) and the strongest antioxidant activity (53.3 mg g–1 AAE) were measured in the population originated from Budapest (GLE 6), harvested in July. The highest chlorogenic acid (357 mg/100 g) and rutin (950 mg/100 g) contents were detected in the July harvested samples from the Soroksár Botanical Garden population (GLE 1). According to our results, the collection time has significant effect on the total phenolic content – first of all on the chlorogenic acid and rutin accumulation levels of ground ivy, while the influence of the habitat seems to be less important.
The society is changing faster and faster. The technical development times are constantly growing shorter, whereas the rate of development is increasing exponentially. Hence, the treatment of the environment is also changing. The society responds to these changes by becoming more and more flexible and adapts itself to new situations.
In contrast to this, the construction is static and the construction industry is conservative. The further development of construction methods and materials is also slow. For centuries, the same materials have been used.
The requirements to living space become more and more multiple. Dwellings are usually made for one use, one setting of requirements. The result is a growing vacancy of dwellings. The shown project, which is under realization at the moment is coming up with one possible solution for a dwelling to use it with multiple requirements.
Authors:Stanislav Kelčík, Tatiana Pindjaková and Andrej Šoltész
The Slovak lowlands have been threatened by floods recently. The Levice district is one of the regions endangered by floods from extreme hydrological situations. The investigated river, which passes through this district is the River Podluzianka with the Cajkovsky brook and the Rybnicky brook as right-bank tributaries. The present conditions of the flood protection in the Levice district area are not sufficient. For this reason, it was necessary to analyze the river flow regime and propose appropriate flood protection measures in the mentioned region. This evaluation based on hydrological, geological and meteorological information and was performed by numerical modeling using computer code HEC-RAS. The main results of this research are presented in the paper.
Authors:Sorin Abagiu, Ionel Lepadat, Elena Helerea and Cătălin Mihai
This paper deals with the development of a model for assessment of the indicators, which characterize the unbalanced and harmonic distorted operation regime in the three-phase low voltage networks. The symmetrical components transformation and the Fourier method are applied, in which each harmonic is decomposed into zero, positive and negative sequence components. The quality indicators in voltage distorted and unbalanced regime are obtained using MathCAD software. The proposed model and procedure is applied for specific case studies. This approach allows the identification and analysis of distorted and unbalanced regime indicators of three-phase low voltage supply system in common coupling point of the consumer, and the procedure can be integrated into a power quality monitoring system.
The city of Almere, which is one of the four main cities in the Amsterdam Metropolitan Area, has been among the fastest growing cities in Europe ever since it establishment in 1976. The economic and demographic expansion puts significant pressure on valuable green areas around Amsterdam, and Almere has both space and potential for growth. Already at the time of its creation, the plans of a multiple-core structure city attracted mixed reviews, leading urban designers calling it ‘an anti-city’. However, with time it has developed into a mature, healthy and sustainable urban environment. With the new expansion that would add 60.000 new dwellings and 100.000 new jobs by 2030, the city faces new challenges, which require visionary strategic planning once again.
The intended growth of Almere is planned to take place in an ecologically, socially and economically sustainable fashion. To achieve this and to inspire contribution to future developments, the city has defined seven principles in concurrence with international sustainability experts.
Community participation is one of the strongest principals in this innovative place-making experiment. Creators of the new strategic vision imagine large-scale citizen involvement, bottomup community and private initiative through empowerment and ownership, from the design phase to the implementation. They aim far beyond the design character of the buildings, including among others the design of the urban fabric and the supporting infrastructure as well. This paper intends to describe and examine the potential growth and the urban development of Almere from a complex perspective, with a special focus on community design.
Authors:Zoltán Bán, Tamás János Katona and András Mahler
Numerous methods exist to determine the liquefaction potential of a site due to earthquake, from which the stress-based empirical methods are the most commonly used in practice. Despite of their widespread use, their shortcomings have given way to the evolution of strain and energy-based methods. Their benefits make them a very promising alternative candidate for liquefaction potential evaluation. To reveal differences and uncertainties involved in the different methods, a comparative analysis was performed for the site of the Paks Nuclear Power Plant with the aim of contributing to the safety assessment of the plant with respect to liquefaction effects.
Authors:Ouadia Mouhat, Abdellatif Khamlichi and Ali Limam
Dynamic buckling of stiffened panels under axial compression loading having the form of finite duration pulse was analyzed by finite element modeling. Welding induced defects modifying the skin plate curvature were incorporated. Material degradation in the heat-affected zone was also taken into account. The Budiansky and Roth criterion was employed to predict the collapse load. Various pulse shapes were investigated. The obtained results have shown that the pulse period and profile have severe effects on the buckling strength. For the considered boundary conditions and load pulses up to 56% reduction of the strength was observed in comparison with static buckling.
The paper presents an approximation method for the assessment of the load carrying capacity of masonry arch railway bridges. The method is a simple semi-empirical tool for the initial level assessment that is considered to serve as a first sieve and provides conservative values for the load-carrying capacity and permissible axle load of single-span arches.
The proposed method is based on results obtained by the RING 2.0 masonry arch bridge analysis software. The method uses a closed mathematical formula to calculate the carrying capacity and its input parameters can easily be determined by simple site inspections or using data from bridge files.
When a flood wave passes along the River Danube, the groundwater level rises, hence property is directly threatened and, in particular, the groundwater resources for the water supply located near the affected rivers increase. As the water is polluted during the flood, a solution to this problem is more than necessary. The specific area for this problem - Sihoť Island, was chosen as one of the most significant areas for groundwater supply in Bratislava. This island is flooded repeatedly every year with several floods. Therefore, it is more than necessary to analyze how the groundwater level reacts to the increased water level in the Danube.
The significance of vegetable shading is, that it can minimize the risk of overheating and also the negative effects of urban heat island. The aim of the paper is to analyze more precisely the shading effect of alley trees, and their impact on indoor comfort.
The shading efficiency of trees is a species-specific attribute, because of the varying crown structure and leaf density. The analyses aimed the quantification of the transmissivity of characteristic individuals of three frequently planted species. On the base of measured data the cooling load of the buildings and the risk of summer overheating are calculated.
Authors:Tatiana Pindjaková, Stanislav Kelčík and Andrej Šoltész
In Slovakia, the year 2011 can be characterized as dry with an irregular distribution of rainfall during the whole year. However, there were also some important hydrological events in form of flash floods. One of them a flash flood on the River Gidra, which passes the village of Píla situated below the Small Carpathians. A numerical simulation of this type of flood event was the main goal of the research in order to avoid the future devastating consequences of these kinds of floods. It was necessary to setup a mathematical model of the river using the HEC-RAS modeling tool to develop a correct evaluation of the flood course and to design appropriate flood protection measures, which will enable the interception of flood waves and to protect people and their property.
Authors:Bálint Baranyai, Bálint Bachmann and István Kistelegdi
Getting the possibility to participate in an actual design process of a Hungarian national sports center is a unique chance to demonstrate and investigate the potential of the dynamic simulation supported building design research program. The research is based on synchronous energy simulations and architectural planning. Energetic and climatic simulations are made during the whole design process. All possible simulated building climate- and energy parameters of the planned versions are compared to each other. In this way it is possible continuously develop the energy and climate characteristic of the designed building. The goal is to reach an accurate design method to be able to predict and minimize the total energy needs of the building as early as the design stage. In the first phase of this process the simulation models of the plan variations are compared, which helps to locate the possible weaknesses of the proposed building geometry and structures or its setting method to develop he building structures and proposed building services systems. In the second phase the chosen building plan is optimized and quantified by final simulations.
Visegrád, with its 1800 inhabitants, is considered to be the smallest town of Hungary. The development of the town center is a fine example for how the original exaggerating ideas were altered due to the economic crisis - besides its negative effects - and facilitated the birth of a sustainable development, satisfying the continuous needs of the local community and the temporary demands of tourism.
The paper represents the rapidly developing cities in China, namely Shanghai. The metropolis has become a show-case city of the Chinese economy in the last couple of decades. By means of vast investments Shanghai is constantly being renewed and re-edified. The goal of the paper is to present the transformation of the existing conditions, related to public spaces through scientific and empirical elements.
Two new periodical space-filling mosaics will be constructed. These are based on a 3D model of the 10D cube. The initial edges have the same lengths and are placed rotation symmetrically around an axis, thus the model is a specifically arranged zonotope. Each mosaic consists of this model and some derived ones of lower-dimensional parts of the 10D cube. These two tessellations complete the construction series based on similar models of 3-12D cubes except the 11D one.
Retrofit of the old building stock presents a good possibility to reduce the energy consumption. However, as the envelopes of old buildings become tighter, a risk increases that the fresh outside air supplied to the indoor environment by natural infiltration can decrease below the amounts required for a comfortable indoor environment, especially in buildings where mechanical ventilation has not been installed. This study presents an efficient method to measure the ventilation intensity, demonstrated on a 40-years old high-rise office building after a complete envelope retrofit. The well-established tracer gas decay and tracer gas step-up method were employed to obtain the ventilation intensity, using the natural CO2 produced by the occupants as the tracer gas. The measured values of the air change rate were between 0.1 and 0.7 1/h for the simple façade, whereas it ranged from 0.2 to 0.5 1/h for the double skin façade, with the windows closed. The level of compliance with ventilation requirements varied, depending on the standard and the philosophy adopted.
Authors:A. Csikos, A. Hodzic, E. Pasic-Juhas, A. Javor, A. Hrković-Porobija, T. Goletic, G. Gulyas and L. Czegledi
Species identification in food has become a prominent issue in recent years as the importance of consumer protection has increased. DNA-based species identification methods were developed by researchers in the last two decades, as these are reliable, accurate, and low-cost techniques for species identification in raw and processed food products as well. In our study, universal primers were designed to conserved regions of mitochondrial 12S rRNA. Amplicons were heat-denatured and a PCR single strand conformation polymorphism (SSCP) method was developed to identify cattle, buffalo, sheep, and goat DNA. Sensitivity of this technique was tested on DNA mixtures of cattle-sheep, cattle-goat, and cattle-buffalo and the threshold limit of cattle DNA was 5%, 5%, and 3%, respectively. One hundred and five cheeses were purchased and collected from Bosnian and Hungarian farmers, retails, and supermarkets to reveal fraud, 32 percent of them (34 cheeses) were found to be mislabelled by species.
Authors:Y. Li, F.Q. Lu, Y. Feng, Z.D. He and X.L. Wu
Analysis of the binding interaction of (−)-epigallocatechin-3-gallate (EGCG) and pepsin is important for understanding the inhibition of digestive enzymes by tea polyphenols. We studied the binding of EGCG to pepsin using fluorescence spectroscopy, Fourier transform infrared spectroscopy, isothermal titration calorimetry, and protein-ligand docking. We found that EGCG could inhibit pepsin activity. According to thermodynamic parameters, a negative ΔG indicated that the interaction between EGCG and pepsin was spontaneous, and the electrostatic force accompanied by hydrophobic binding forces may play major role in the binding. Data from multi-spectroscopy and docking studies suggest that EGCG could bind pepsin with a change in the native conformation of pepsin. Our results provide further understanding of the nature of the binding interactions between catechins and digestive enzymes.
Authors:A. Kanghae, J. Monkai, P.D. Eungwanichayapant, P. Niamsup and E. Chukeatirote
In this study, two bacilli strains, namely TN51 and TN69, previously isolated from Thua Nao, a Thai traditional fermented soybean, were studied in terms of their phenotypic and biochemical properties. Initially, both strains were subjected to morphological determination and a series of biochemical tests. Both were Gram-positive, endosporeforming bacilli. Based on 16S rRNA gene sequence analysis, the identities of strains TN51 and TN69 were confirmed as Bacillus subtilis and B. cereus, respectively. In addition, these two strains were also assessed for their antibiogram profiles. It was found that both strains were susceptible to chloramphenicol, erythromycin, kanamycin, tetracycline, and vancomycin and resistant to ampicillin and intermediately susceptible to bacitracin.
King oyster mushroom (Pleurotus eryngii) is a worldwide cultivated mushroom of appreciated nutritional and medicinal quality. Aims of these investigations were to give new comparative data for the better evaluation of P. eryngii. Results of our investigations can be summarized as follows:
P. eryngii has higher (crude protein, crude fat) or at least the same concentrations (chitin and total carbohydrate) of organic nutritive components than the common cultivated Pleurotus hybrid (‘HK-35’). Regarding the classical protein fractions: albumins are the highest content in both mushrooms, but the quantity and the proportion in P. eryngii is better than in ‘HK-35’ hybrid. Occurrence and proportion of protein fractions is more valuable in P. eryngii, while the NPN contents of both mushrooms are the same.
The investigated soluble oligo- and polysaccharides were present in high amounts in both mushrooms, but the free radical scavenging activity seems to be markedly higher in king oyster mushroom, making it more valuable. Mineral compositions of both species are similarly beneficial, but P. eryngii has basically higher P and lower K levels. More intensive cultivation and use of P. eryngii is clearly recommended.
Authors:G. Banerjee, A. Ray, S.K. Das, R. Kumar and A.K. Ray
Present study demonstrated the isolation of most promising β-galactosidase producing bacterial strain SB from soil. Morphological, biochemical, and 16s rRNA sequence analysis identified the bacterial strain as Arthrobacter oxydans. Several chemicals, including SDS, Triton X-100, Tween 20, isoamyl alcohol, and toluene-acetone mixture, were applied for extraction of intracellular β-galactosidase from the bacterial strain Arthrobacter oxydans. Among these, Tween 20 was recorded to be most effective. Role of pH, temperature, and shaker speed on production of β-galactosidase was evaluated using Box-Behnken design of response surface methodology. According to Box-Behnken analysis, optimum production of β-galactosidase (21.38 U (mg–1 protein)) is predicted at pH 6.76, temperature 36.1 °C, and shaker speed 121.37 r.p.m. The parameters are validated with the nearest value.
Authors:E. Tománková, J. Balík, I. Soural, P. Bednář and B. Papoušková
This study presents findings from comparing the properties of anthocyanin pigments: i. malvidin-3-glucoside (Mal-3-G), the most significant anthocyanin present in young red wine; ii. Vitisin A (5-carboxypyranomalvidin-3-glucoside), a major product from a reaction induced in red wine between Mal-3-G and pyruvic acid during its ageing. These pigments were determined and compared to the absorption spectrum in 200–770 nm at various pH values, such results including the ability of cation Al3+ to change the values of absorbance. Changes in the colour parameters L* a* b* were determined in the CIELAB colour space of Mal-3-G and Vitisin A in relation to pH and the addition of AlCl3. Both coloured compounds were investigated for their resistance to discoloration by sulphur dioxide. Total antioxidant activity was evaluated by two methods (FRAP, DPPH), and the values were compared to other phenols.
Authors:K. Jurica, I. Brčić Karačonji, D. Lasić, D. Vukić Lušić, S. Anić Jurica and D. Lušić
Phthalates are ubiquitous environmental contaminants that, due to their lipophilicity, migrate more readily into beverages with higher ethanol content. The aim of this work was to study the occurrence of phthalates in samples during the plum spirit production and in the final product, plum spirit manufactured by registered producers from five European countries, using gas chromatography-mass spectrometry (GC-MS). A decreasing trend of mean values was observed for diethyl phthalate (DEP), di-iso-butyl phthalate (DiBP), and di-n-butyl phthalate (DBP) as the distillation process went on. Levels of benzyl-butyl phthalate (BBP) and di-(2-ethylhexyl) phthalate (DEHP) increased in the distillation phase compared to concentrations in the preceding phases. In commercial plum spirits, DEHP and DiBP were detected in the highest concentrations. Results also indicated that a moderate daily consumption of plum spirit does not pose a health risk regarding the Tolerable Daily Intake of BBP, DEHP, and DBP
In a 120 min osmotic dehydration procedure followed by an air drying process, the effect of carboxy-methyl cellulose (CMC) on some qualitative characteristics of apple slabs including browning index (BI) and rehydration capacity were studied. Moreover, the relation between textural and sensory properties, such as hardness, cohesiveness, springiness, adhesiveness and chewiness, was investigated. Samples containing higher coating concentrations (1–1.5%) showed higher rehydration capacity and lower browning index compared to those with lower coating concentrations (0.25–0.5%). Weibull distribution model was used to investigate the effect of coating concentration on drying kinetics. The results of sensory tests showed that the overall acceptance of samples is increased with decreasing coating concentration, and an appropriate correlation was found between sensory properties and textural parameters.
An extruded product was made based on oats and dried green pea using central composite rotatable design. Effects of incorporation level of oat flour (OF, 15.86 to 44.14%) and dried green pea flour (DGPF, 7.93 to 22.07%) on the physical and functional characteristics of extruded products based on composite flour were studied using response surface methodology. Second order polynomial equation was used to describe the effect of OF and DGPF on lateral expansion (LE), bulk density (BD), water solubility index (WSI), water absorption index (WAI), and hardness (HD). Results indicated that OF had negative effect on LE, while positive effect on BD, WSI, WAI, and HD. On increasing DGPF, LE and WSI increased, but it had negative effect on BD, WAI, and HD. Numerical optimization resulted in 41.91% OF and 7.93% DGPF to produce acceptable extrudates. The results suggest that oats and dried green pea flour can be extruded with rice flour and corn flour into an acceptable snack food.
Authors:M. Ferreira, S. Pereira, A. Almeida, R. Queirós, I. Delgadillo, J. Saraiva and A. Cunha
The main objective of the present study was to evaluate the effect of temperature and different compression/ decompression rates on the efficiency of Listeria inactivation by HPP.
Stationary phase cultures of Listeria innocua were subjected to 300 MPa for 5 min at 4, 10, and 20 °C using different compression and decompression rates. Inactivation was more efficient at low temperature and with lowest compression and decompression rates (1.5 MPa s–1 and 3.2 MPa s–1, respectively).
Kinetics of pressure building up and decompression, as well as temperature, have a significant impact on the outcome of Listeria inactivation by HPP. The results may contribute to the design of HPP protocols that ensure food safety, while preserving nutritional and organoleptic properties better.
Authors:B. Kucska, T. Feledi, Á. Adorján and T. Molnár
This study investigated the effects of three different commercial diets on the growth, feed utilization, and product quality of pike (Esox lucius). The first diet had low lipid (12%) and low protein (37%) (diet A) content, the second diet had low lipid (12%) and high protein (52%) content (diet B), the third diet had higher lipid concentration (15%) and high protein content (52%) (diet C). Two hundred and seven pike were stocked in an experimental RAS (Recirculating Aquaculture System) and were fed ad libitum for the duration of the nine week trial. Specific growth rates, feed conversion rates, protein utilization, as well as body composition and somatic indices were calculated. Fish fed with diets B and C had significantly better SGR (Specific Growth Rate) and FCR (Feed Conversion Rate) than fish fed with diet A. The higher dietary lipid concentration does not cause significantly better protein utilization. Moreover, it had a negative effect on the product quality by increasing the body lipid concentration and the visceral fat deposition.
Authors:H.B. Coban, A. Demirci, P.H. Patterson and R.J. Elias
Alpha keto acids are important food additives, which commonly produced by microbial deamination of amino acids. In this study, production of phenylpyruvic acid (PPA), which is the alpha keto acid of phenylalanine was enhanced in 2-l bench scale bioreactors by optimizing of fermentation medium composition using the Box-Behnken Response Surface Methodology (RSM). Optimum glucose, yeast extract, and phenylalanine concentrations were determined to be 119.4 g 1−1, 3.7 g 1−1, and 14.8 g 1−1, respectively, for PPA production, and 163.8 g 1−1, 10.8 g 1−1, and 9.8 g 1−1, respectively, for biomass production. Under these optimum conditions, PPA concentration was enhanced to 1349 mg 1−1, which was 28% and 276% higher than the unoptimized bioreactor and shake-flask fermentations, respectively. Moreover, P. vulgaris biomass concentration was optimized at 4.36 g 1−1, which was 34% higher than under the unoptimized bioreactor condition. Overall, this study demonstrated that optimization of the fermentation media improved PPA concentration and biomass production in bench scale bioreactors compared to previous studies in the literature and sets the stage for scale up to industrial production.
Environmental factors, including temperature and nutrient composition, have considerable impact on the growth dynamic of each microbial species; moreover it is strongly dependent on the selected strain. Therefore, the aim of this study was to describe and analyse the growth dynamics of the strain Lactobacillus acidophilus NCFM (Howaru) by predictive microbiology tools. The intensity of Lb. acidophilus NCFM growth in MRS broth and in milk was significantly affected by the incubation temperature described by the Gibson’s model, from which the optimal temperature for the Lb. acidophilus growth of 40.5 °C in MRS broth and 40.1 °C in milk was calculated. These cardinal temperatures were verified with the CTMI model providing also other cardinal (minimal Tmin, maximal Tmax, and optimal Topt) values for Lb. acidophilus NCFM growth Topt=40.2 °C, Tmin=15.4 °C, Tmax=46.0 °C and Topt=40.3 °C, Tmin=14.3 °C, Tmax=46.6 °C in MRS broth and in milk, respectively.
Authors:K. Török, L. Hajas, V. Horváth, E. Schall, Zs. Bugyi and S. Tömösközi
The weaker performance of generally used analytical methods for allergen analysis in processed foods can be connected to protein denaturation. To understand the nature of protein denaturation processes, experimental but realistic model matrices (corn starch based mixture, hydrated dough, and heat treated cookies) were developed that contain a defined amount of milk, egg, soy, and wheat proteins individually or in combination. The protein subunit composition was investigated in every processing phase, i.e. after mixing, dough formation, and baking. SDS-PAGE measurements were carried out to monitor the protein distribution of sample food matrices in non-reducing and reducing gels. The results clearly show that the highly decreased protein solubility is caused by denaturation, aggregation, or complex formation, which are the most significant factors in poorer analytical performances. Solubility can only partly be improved with the application of reducing agents or surfactants, and the rate of improvement is depending on the proteins and the matrices.
Authors:Ü. Gürer Soyogul, I. Omurtag Korkmaz, M. Ulusoylu Dumlu and G.Z. Omurtag
This study was conducted to determine the recent level of contamination with Fumonisin B1 (FB1) and Fumonisin B2 (FB2) in major medicinal plants and to assess consumer exposure in northern Turkey. FB1 and FB2 were investigated by using high performance liquid chromatography (HPLC) with fluorescence detection after derivatization with o-phthaldialdehyde (OPA). A total of 78 homemade medicinal plant samples from 14 species were analysed. The recovery in thyme was 67.2±5.2% for FB1 and 80.8±14.3% for FB2 spiked with 1 μg g–1 of each analyte. The minimum detectable amount for the OPA derivatives of FB1 and FB2 were 1 ng per injection and 2.5 ng per injection, respectively. The limit of quantitation (LOQ) S/N=10 was 0.078 and 0.313 μg g–1, and the limit of detection (LOD) S/N=3 was 0.023 and 0.093 μg g–1 for FB1 and FB2, respectively. FB1 was detected in thyme (0.125) and mint (0.125 and 0.256 μg g–1) samples; however. FB2 toxin was below the detection limit in all samples. These results indicate that toxins might be present in homemade medicinal plants; however, the risk of exposure to fumonisins by the consumption of those plants was lower than the estimated TDI limits (<2 μg kg–1 bw).
Creep-Recovery Tests (CRT) were measured with a Stable Micros Systems TA.XT-2 precision penetrometer with 75 mm diameter cylinder probe and with different loading stress and creeping-recovery times on gelatine-based candy gum samples, purchased from the local market. The loading force changed from 1 N up to 10 N and the creeping time varied from 30 s up to 120 s. The creeping and the recovering part of CRT curves were approached by Burgersmodel with stretched exponential function. The two elastic moduli and the two viscosities increased linearly in the function of the applied stress. One elastic modulus and the two viscosities also increased, but another elastic modulus slightly decreased in the function of the creeping time. The stretching exponent β practically linearly decreased as the creeping time increased. Based on theoretical considerations, the Kelvin-Voigt-element of Burgers-model can describe the rheological behaviour of sugar content, and the Maxwell-element of Burgers-model can describe the rheological behaviour of gelatine-mesh.
Authors:N. Koczka, A. Ombódi, Z. Móczár and E. Stefanovits-Bányai
Total phenolic content and antioxidant capacity (FRAP method) of Ginkgo biloba L. leaves and of different commercial ginkgo teas were determined and compared. Different water extracts (infusions and decoctions) were prepared varying the time of infusing, boiling, and steeping, and also aqueous ethanolic (water/ethanol 80/20 v/v) extract was made.
Total phenolic contents and FRAP values of collected ginkgo leaves were similar to those of commercial ginkgo mono teas, while these parameters were significantly higher for ginkgo teas containing ginseng or green tea. Decoction was more effective than infusion for extracting antioxidative compounds, in contradiction to suggested preparation methods by the producers. Aqueous ethanolic extracts had significantly higher total phenolic content and antioxidant capacity than water extracts. The correlation between phenolic content and FRAP values was very strong and positive for water extracts of collected leaves, while it was weak and negative for the tea products.
The objectives of this publication are the analysis of surfaces and edges of a new geometric spiroid hob with arched profile in axial section and the definition of their equations for computer modelling. On the basis of this we will work out the CAD model of hob for our further geometric calculations.
Authors:Z. Jrad, H. El Hatmi, I. Adt, T. Khorchani, P. Degraeve and N. Oulahal
The aim of this study was to evaluate the antimicrobial activity of camel caseins and their hydrolysates by gastrointestinal proteolytic enzymes against 3 Gram-positive and 2 Gram-negative bacterial strains. Camel caseins (CN) were hydrolysed by successive action of pepsin and pancreatin. Hydrolysis of CN was checked by electrophoresis and gel filtration chromatography (GFC). Both techniques showed that CN was hydrolysed into peptides. Among the tested bacteria, a decrease of 19.3%±0.02 of E. coli XL1 blue cells growth was observed in the presence of undigested camel casein at a concentration of 20 mg ml−1. After successive hydrolyses by pepsin and pancreatin, camel milk casein hydrolysates still exhibited anti-bacterial activity against E. coli XL1 blue strain (19.73±0.01% growth inhibition under the same conditions). Gram-positive strain growth was not affected by intact camel CN, while, at the same concentration (20 mg ml–1), their hydrolysates slightly inhibited the growth of these bacteria. This suggests that antibacterial peptidic fragments of caseins were generated by pepsin and pancreatin.
This study is aimed at performing the determination of bioactive compounds, antioxidant activity, and the identification of the minerals in the flours produced with the tropical fruit peels of mango, papaya, melon, and pineapple. The results showed that the papaya peel flour has the highest amount of ascorbic acid and lycopene when compared with the other studied flours. The mango peel flour has a high content of total extractable polyphenols and a high antioxidant activity. Regarding the mineral content, the by-product of melon stood out with 523.24±26.12 mg/100 g of potassium, 104.15±3.52 mg/100 g of calcium and 6.62±0.30 mg/100 g of iron. The flours prepared with mango, papaya, melon, and pineapple peels are potential sources of bioactive compounds and minerals, also presenting good antioxidant activity, being, therefore, recommended to be used in food products to improve the nutritional quality of the product.
This paper presents an axisymmetric formulation of the circuit-coupled finite element method embedded in closed loop control system. The controller checks the current of the coil of the magnetic system after each time step and controls the applied voltage to reach the steady state faster. The results of the voltage driven finite element model are compared with the results from the analytical model. The control parameters for the proportional-integral-derivative controller were estimated using the step response of the system. Furthermore, the results of the closed loop system simulation show why the model accuracy is important in the controller design.
Authors:Viola Hospodarova, Jozef Junak and Nadezda Stevulova
Nowadays, color concrete pigments are used to revive space in the construction of new buildings, reconstruction existing buildings and squares. Color pigments represent a partial weight replacement of the binder. Color pigmented concrete also has properties like traditional concrete namely high strength, good durability and weather resistance for its variable use. In this paper, characterization and classification of color pigments, using and their influence on the properties of concrete is given. The experimental part of concrete composites studying (with color pigments) includes testing of physical and mechanical properties in comparison to reference sample (without color pigments).