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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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The present study investigated how sighted and blind sensory assessors evaluated the quality of various apple varieties: Regal Prince (Gala Must), Jonagold Schneica (Jonica), Watson Jonathan, Golden Reinders and Generos. A total of 80 sighted and 12 blind people participated in the study, in three groups (sighted people without blindfolds, sighted people with blindfolds, blind people). The preference of sensory attributes (size, shape, colour, texture, taste and odour) was evaluated on a six-category scale. The data were analysed using single-factor (ANOVA, LSD95%, 99%) and multi-factor (Cluster analysis, ANOVA, LSD95%, 99%) evaluation. The results showed that blind and sighted assessors made similar judgements on external attributes perceptible by touch (size, shape), but differed in their evaluation of certain quality factors (flavour, taste), resulting in opponent patterns of preference on some apple varieties (Generos, Jonagold Schneica). A further conclusion of the experiment is that there was less deviation between the judgements of sighted assessors when they saw the apples than when they were blindfolded. The background of this phenomenon might be explained by the uncertainty and disturbed perception, which lead to inconsistent judgements.

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The aim of the study was to investigate changes of photosynthetic efficiency, amount of photosynthetic pigments, superoxide dismutase (SOD) enzyme activity, and rate of lipid peroxidation in bean-rust interaction. The clarification of the role of the above changes involved in the defence mechanism can significantly contribute to the breeding of plant varieties with natural resistance. Consequently, the amount of chemicals used in food production can be significantly reduced. In the present study some principal physiological parameters, such as the relative chlorophyll content of the host plant, the amount of photosynthetic pigments, changes in photosynthetic efficiency, and the activity of superoxide-dismutase (SOD) in addition to rate of lipid peroxidation (LP) were measured. The experiment was conducted in a humidity tent. Significant decrease in the relative chlorophyll content and in the amount of photosynthetic pigments was measured. At both sampling times, an increase was found in superoxide-dismutase enzyme activity and in rate of lipid peroxidation due to the bean rust infection. Notably, in several cases the differences were significant. The results indicate that the above parameters have important role in the bean-rust interaction, which should be taken into consideration in resistance breeding.

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Our study involved assessing new Hungarian multi-resistant apple cultivars (‘Artemisz’, ‘Hesztia’, ‘Rosmerta’, and ‘Cordelia’) and two commercial cultivars (‘Watson Jonathan’ and ‘Prima’). The samples were evaluated by a trained assessor panel applying computer supported profile analysis with 20 descriptive sensory parameters (using ProfiSens sensory assessment software). Beside the profiles of each cultivar we also showed the significant differences between the cultivars (LSD95%, LSD99%). The nutritional values were analysed using the MANOVA statistical method, the effects of significant factors on measured values were evaluated by using Tukey (P=0.05) post-hoc test, and we determined the homogeneous and heterogeneous groups based on that. Our study showed that PCA bi-plots containing sensory and instrumental value loadings together with the scores of apple cultivars make the complex relationships of each cultivar available for comparison. The results clearly showed that the intensity of the sour taste is inversely proportional to the carbohydrate-acid ratio determined by measurements. The flesh firmness and pectin content values obtained by instrumental measurements were found to be strongly correlated sensory parameters on crispness, texture, and ripeness. PCA plots proved to be very useful in demonstrating the parallelisms between instrumental-instrumental (TPC/FRAP) and sensory-sensory (shade/colour) parameter pairs, too. Our aggregated results show that the new Hungarian resistant apple cultivars have almost as good as or even better nutritional values than ‘Prima’ and ‘Jonathan’ (the latter dominated the Hungarian apple production for several decades). The new multi-resistant cultivars renew the range of apple cultivars available on the market, and they introduce new flavours to consumers.

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Acta Alimentaria
Authors: V. Losó, A. Tóth, A. Gere, J. Heszberger, G. Székely, Z. Kókai, and L. Sipos

According to international studies the consumer preference of apple varieties is defined by the flavour and texture and the consumers’ opinion about the heavily sour character, the mushy texture and the barely chewable peel is negative. However, the preference level and nutritional values of the apple juices are determined by the variety used, the maturity level and the processing of the fruits. In our study we conducted the external and internal preference mapping of two apple juices with 100% fruit content according to the industrial practice. It propounded several questions about the method of the preference mapping which were the following: product specific training of the assessors, panel performance monitoring, number of samples, representativity, scale use and marking, reasons of the singular matrix, segmentation method, segmentation criterion, power of the paired post-hoc analysis, number of the principal components (PC’s), etc. Finding the answers of the questions above it is possible to establish a good preference mapping practice.

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Colour (L*, a*, b*, h o and chroma), β-galactosidase, polygalacturonase (PG) activity, pectin content, ultrastructure and volatile compounds were determined, in mature green and in yellow ber fruits ( Zizyphus mauritiana Lamk. cv. Umran).The L* did not, but a*, b* and h o significantly differed between mature green and yellow ber fruit. The pectin content and its solubilization (soluble pectin and neutral sugars), the activity of PG was higher in yellow ber fruits and in the outer part of fruits. Activity of β-galactosidase was higher in mature green ber fruits. The cell walls of mature green fruits were usually homogeneous, the density of the middle lamellae decreased in yellow bers, and at the same time, the structure of chloroplastids disintegrated. The aroma of yellow ber is characterized by the presence of even carbon number of ethyl esters from C4 to C14.

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Acta Alimentaria
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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Nanopages
Authors: E. Horváth, P. L. Neumann, A. L. Tóth, É. Vázsonyi, A. A. Koós, Z. E. Horváth, P. Fürjes, C. Dücső, and L. P. Biró

The deposition of nanowires for interconnects in nanoelectronic devices werestudied morphologically by scanning electron microscopy (SEM), atomic force microscopy (AFM) and by in-situ resistance measurements. The deposition and basic characterization of nanometer size tungsten wires by gas injection (GIS) and focused ion beams (FIB) was carried out in-situ in a LEO 1540 XB workstation. The I(V) measurement showed that the deposited W wires have ohmic characteristic. The variation of the resistance during an ex-situ heating was linear with a low thermal coefficient (4% of the pure metallic W).

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