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Abstract

The main goal of this study is firstly to model the phenomenon of advection and diffusion of the gaseous residues of coal combustion. On the other hand, to study the dispersion of this pollution by varying the parameters like the wind and the resources of pollution, where there are four emissions: SO2, CO, NO2 and PM10. The present model will compare estimating concentrations with the results found by the contribution of the thermal power plant of Jerada city, where the American Environmental Regulatory Model is used. The results suggest that SO2, PM10, NO2 and CO concentration simulated by turbulent k-ε model in combination with the transport model of diluted species, at the 3h and 24h intervals, greater than their respective observed concentrations compared with the American Environmental Regulatory Model. The concentrations of the model found are very high and exceed the limit values under the study conditions. Indeed, the simulated model was used in 2D with a very low wind speed (10−4 m/s) and in the absence of gravity, hence the total neglect of altitude because the two sources of pollution are at the height of 120 m.

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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.

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Herbal teas may be effective in adjuvant therapy for the prevention of complications of diabetes mellitus II. Agrimoniae herba, Betulae folium, Bursae pastoris herba, Foenigraeci semen, Galegae herba, Maydis stigma, Taraxaci radix, Phaseoli fructus sine seminibus, Urticae folium, and their teas were analysed by ICP-OES for element content. Concentration of the elements of crude drug samples obtained are in good agreement with the average concentrations of plants, although some significantly high concentration has been found for manganese (893 mg kg-1), zinc (275 mg kg-1) and iron (492 mg kg-1) in Betulae folium, for copper (41.2 mg kg-1) in Galegae herba, for iron (2692 mg kg-1) in Taraxaci radix, for calcium (41210 mg kg-1) and magnesium (6275 mg kg-1) in Urticae folium. The common characteristic feature of crude drugs is the relatively high concentration of chromium (0.8-16.3 mg kg-1). Ion concentrations of teas are relatively low. The quantities of metal ions do not cover the daily needs, nevertheless, they may be important as food supplements. According to U.S. Recommended Dietary Allowances (RDA), the following teas are good sources: Agrimoniae herba for chromium, Betulae folium for manganese, Taraxaci radix for copper and chromium, Urticae folium for potassium and calcium. The dissolution of elements from plant drugs varies: potassium (22.5-74.7%), sodium (1.9-60.5%), calcium (6.6-28.1%), magnesium (12.3-52.5%) and copper (3.7-51.4%) are readily dissolved. The dissolution of manganese (6.8-32.3%) and of zinc (0-31%) is lower. The dissolution of chromium from Agrimoniae herba (9.55%) is significantly higher, while the dissolution ranges from other plant drugs are between 0-5.9%.

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/4 807 812 Dragun Z., Roje V., Mikac N., Raspor B. Preliminary assessment of total dissolved trace metal concentrations in Sava River water, Environmental Monitoring and

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Acta Alimentaria
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

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The aim of this study was a survey of relationships used for calculating ‘meat content’ with respect to the QUID regulation (Commission Directive , 2001). The recommended equations are presented in a concise form. The advantages of a possible introduction of the meat equivalent concept are also treated [assessment of lean content of the meat ingredient(s)]. A non-negligible condition for applying the QUID equations is, in principle, the equality of the fat-free protein concentrations of the various tissue types in the raw meat materials. This needs an adjustment of the protein concentrations of the recipes to a reference value (PFFref), which can be achieved by effective or virtual addition of water to the formulation or ‘removal’ of water from it. The influence of moisture loss during meat processing on QUID is also discussed. The results of various calculation methods are presented with examples.

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The aim of the present study was to test the antioxidant activity of rosemary extract and its mixture with propylene glycol on the stability of fat in butter. Rosemary extract was added at a concentration of 0.02% (w/w) and mixture of rosemary extract with propylene glycol at a concentration of 0.25% (w/w) to the cream before churning. For comparison, control samples without added antioxidant were also prepared and tested. Samples were stored at 4 °C and at 20 °C for 27 days and their peroxide values were determined periodically. The measurement of peroxide values for butter at 60 and 98 °C was also performed. Activity of rosemary extracts was compared with synthetic antioxidant BHT. The rosemary extract and its mixture with propylene glycol exhibited strong antioxidant activity in butter when added to a cream before churning and in an aqueous emulsion system of β-carotene and linolenic acid.

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The objective of this work was to study the effect of nisin, alone or combined with sucrose laurate ester (SL), on enhancing Bacillus amyloliquefaciens Fad 82 spores inactivation by pressure-assisted thermal processing (PATP). Spores of B. amyloliquefaciens (108 CFU ml−1) were suspended in sterile phosphate buffer saline (pH 7.6) with concentrations of nisin (0, 100, 200, 1000, 1500 and 2000 IU ml−1) and 1.0% of SL, and combinations of nisin (1000, 1500 and 2000 IU ml−1) and SL (1.1%), and treated by PATP (700 MPa and 105 °C, for 1 min). Nisin did not show any synergetic effect with PATP in all the concentrations tested. Instead, 1.0% of SL alone was effective in enhancing inactivation.

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The objective of this study was to characterise and compare the quality of the MSMs obtained from carcasses from breeding and laying hens to provide useful information for the processing industry. The composition of the mechanically separated meat (MSM) varied between the two groups. Laying hens contained the most crude protein (P<0.05) and high ash content (P<0.05). Calcium concentrations and bone contents were higher (P<0.05) for laying (448 mg/100 g and 1.25%, respectively) than for breeding hens (299 mg/100 g and 0.78%, respectively). Levels of unsaturated fatty acids for laying and breeding hens (75.89 and 72.82%, respectively) and cholesterol concentrations (73 and 61 mg/100 g, respectively) were higher (P<0.05) for laying hens than for breeding ones.

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Phase diagrams of aqueous whey protein (WP) and polysaccharide (PS) mixtures, including carboxymethylcellulose (CMC), k-carrageenan (C) and locust bean gum (LG) are presented in this paper at pH from 5.0 to 7.0 with 0.1 to 0.5 M NaCl. Thermodynamic incompatibility of WP-CMC, WP-LG and WP-C systems increased as pH was close to the isoelectric point of WP (pI=5.2). Increasing salt concentration (0.1 to 0.5 M) increased the incompatibility of WP-LG and WP-CMC systems. However, the effect of NaCl on thermodynamic incompatibility of WP-C was the opposite, i.e. increasing salt concentration decreased the thermodynamic incompatibility of the system. The type of the polysaccharides was the critical factor, which affected the compatibility of WP-PS systems. The thermodynamic compatibility of WP-PS systems decreased in the following order: locust gum ≯ carboxymethylcellulose ≯ k-carrageenan.

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