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As it is well known, the non-thermal plasma discharge is an effective way to clean the flue and exhaust gases of hazardous pollutants, like sulphur-oxides, nitrogen-oxides. The decomposition ratio of these substances depends on the gas composition, concentration, energy distribution of fast electrons, and other parameters. For a detailed analysis of the phenomena, the first step is the mathematical description of corona pulses which determines the electric field. The second step is the determination of the electric field distribution inside the reaction chamber.In this paper the authors give an easy model for the pulsed corona current and a simplified model for the electric field by using the corona current and the displacement current pulse shapes. The result of the model is the space and time dependent field distribution, which is suitable for calculating the rate coefficients of chemical reactions.

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

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

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

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

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

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The changes in the activity of enzyme polyphenol oxidase, the concentration of total soluble phenolic compounds and soluble protein content in different tobacco cultivars (Virginia and Burley) during cultivation, then in a combined curing model system were studied. The latter was a special combination of air-curing and flue-curing methods followed by a long fermentation period to optimize the treatment of tobacco plants used both as protein sources and starting materials in tobacco industry. The results suggest that a cultivation period of 13–14 weeks could be better for tobacco plants as protein sources, however, for starting materials for industrial use 16–17 weeks are optimal. It was found a four-week curing period could be the best for two tobacco cultivars (Virginia and Burley) in the case of using them both as protein sources and starting materials in tobacco industry.

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The yeast biomass, remaining after drawing off the young wine, has not entirely lost either its viability or its fermentative capacity. There have been studies on the possibilities of yeast reusing in a fermentative process in order that an alcoholic liquid should be obtained either for vinegar production or for distillable alcohol. High CO2 level was obtained when a 20% saccharose concentration in syrup was established. Inoculating 20% residual wine yeast, the maximum fermentative activity occurs after two days. The study results suggest the residual wine yeast, which acts upon some syrup, should not have less than 15% or more than 25% sugar in order to avoid a heavy and lingering fermentation or plasmolysis.

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Germinated brown rice received great attention as healthy ingredient and can be used as an alternative source in the malting and brewing industry. The germination capacity, physico-nutritional properties, sugars, and diastase enzyme activity of brown rice affected by germination times and temperature were determined and compared with control. Soaking in water increased the moisture content of brown rice. Germination rate of brown rice was also increased by higher germination time and temperature and reached maximum after 48 h of germination at 35 ºC. However, dry matter loss, grain weight, and density are affected to a lesser extent. Germination significantly (P<0.05) affects the crude protein, fat, fibre, and ash contents. Total carbohydrates content showed linear relationship with germination time and temperature. During germination, hydrolytic enzymes act on starch, reducing its concentration and resulting in higher total and reducing sugars amounts. Increase in germination time and temperature also increased diastase enzyme activity.

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Marinated chicken meat is an ideal substrate for the growth of microorganisms. The aim of this study was to determine the effect of high-intensity ultrasound on the microbial flora of chicken meat marinated in oregano oil. Three concentrations of oregano oil (0%, 0.1%, and 0.3%) and two types of marination (traditional and highintensity ultrasound) were tested. Microorganisms were enumerated immediately after marination and on 7, 14, and 21 days of chilled storage. Marination in oregano oil resulted in significant differences (P<0.05) in the numbers of anaerobic, lactic acid bacteria, and mesophiles. Ultrasound with 0.1% OEO did not show any effect on the three types of bacteria. The treatment with 0.3% oregano oil and ultrasound had the greatest effect on controlling microbial growth. Therefore, a combination of ultrasound and oregano oil is the most appropriate option for reducing the growth of mesophilic, anaerobic, and lactic acid bacteria in vacuum-packed marinated chicken breasts during chilled storage.

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Acta Alimentaria
Authors: C. Cuadrado, É. Gelencsér, M. M. Perdosa, G. Ayet, M. Muzquiz, A. Puszati, György Hajós, and C. Burbano

The effect of germination conditions on the lectin of Lens culinaris var. Magda 20 seeds was studied. The seeds were germinated at 20 °C under different conditions of watering and light and for different periods of time. The seed lectin was assayed by haemagglutination and quantified by competitive ELISA. Changes in lectin content during germination were also monitored by SDS-PAGE and immunoblotting. Haemagglutinating activity and lectin content in the seeds were not changed during the first three days regardless of the conditions of the germination. However, lectin concentration was significantly higher after six days of germination; relative lectin levels being particularly high when germination was carried out in the light and with daily watering. The results of SDS-PAGE and immunoblotting have also shown that the lectin was not degraded during the first six days of germination however, other storage-proteins were broken down by proteolysis.

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

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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.

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A total of 92 corn-based food products consisting of 53 low-processed and 39 processed samples were collected at random from retail markets and bazaars in various provinces of Turkey and analysed for total fumonisin levels. Twenty oneTwenty-one (40%) low-processed and nine (23%) processed samples were found to contain fumonisin. Total fumonisin contamination in the low-processed products ranged from 0.8 to 273 273 mg. mg kg-1, and in the processed products from 0.3 to 76.8 mg kg-. Considering all 92 samples, the highest frequency of detection and also the highest concentrations (in flour samples up to 273 mg kg-1) were detected in low-processed products. These results indicated the natural contamination of fumonisins corn-based low-processed and processed food products for human consumption in Turkey by fumonisins.

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