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Pollack Periodica
Authors: Kalman Buzas, Peter Budai, and Adrienne Clement

One and a half year long field sampling was established in order to evaluate the contamination of storm water runoff. The event means (EMC) total petroleum hydrocarbons (TPH) concentration of the runoff was a function of the actual traffic intensity and the rainfall depth. It was concluded that this TPH, of which dominant component is the engine-oil (characteristically C28) does not form an ‘oil-in-water’ type emulsion in the condition of normal motorway-operation, but is interlocked to asphalt, rubber and soot particles of maximum some ten microns size. This condition influences the possibility, way and extent of separation alike. The separation equipments and their sizing applied so far are not suitable to achieve efficient surface water protection. Practical prevention method of accidental type environment pollution was also suggested. On the basis of the international literature evaluation, technical solutions capable to decrease the runoff pollution were summarized. Among these, useful calculation method was developed for designers to determine the sufficient storage capacity (water quality volume) of reservoirs applied for water quality protection. Monitoring technique of runoffs, which are characterized time dependent, variable pollutant concentrations by their nature, was proposed. It was stated that the administrative regulation should aim at the EMC instead of current concentration. Beside TPH information was gained on polycyclic aromatic hydrocarbons (PAHs), suspended solids, heavy metals, pH, and nutrient (N, P) pollution of the runoff, which are valuable for the grounding of further research results.

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Eight Lactobacillus, five Saccharomyces and one Streptococcus strains were chosen to perform mono and mixed culture fermentations, focusing on interaction investigation via agar diffusion and analysis of cell growth kinetics, both serving as selection criteria. Mixed culture fermentations with four lactic acid bacteria (Lb. bulgaricus, Lb. paracasei SF1, Lb. plantarum 2142, and Lb. casei Shirota) and four yeast strains (S. cerevisiae W66, S. cerevisiae WS34/70, S. cerevisiae W120, and S. carlsbergensis 843) were performed in wort with initial cell ratio of 1:1. It was determined that during fermentations, cell concentration of lactic acid bacteria exceeded that of yeasts by one order of magnitude. Three strain combinations (S. carlsbergensis with Lb. bulgaricus, Lb. 2142, and Lb. Shirota) were chosen for further fermentations. Basic behaviour of them in wort was studied in mono culture, which helped to determine interaction type between bacteria and yeast in mixed culture. It resulted in higher Lactobacillus cell concentration in mono cultural than in mixed culture fermentation, which refers to competition. Cell ratio was changed to 1:10 (lactobacilli:yeasts), to favour growth of yeast and avoid lower pH. Despite the higher initial concentration of yeast, results turned in favour of lactobacillus already at the 24th hour.

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Juniperus phoenicea L. (Cupressaceae) is an evergreen small tree or shrub, distributed throughout the Mediterranean area from Portugal to Israel and North Africa. J. phoenicea has been used for centuries in traditional medicine and its berries are widely used in flavours, perfumes, and to aromatize alcoholic beverages.The aim of the present work was to evaluate the chemical composition and antifungal activity of essential oils of Juniperus phoenicea berries from Jordan.The essential oils of the berries were isolated by hydrodistillation and analysed by GC and GC-MS. Minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the essential oils against dermatophytes, yeasts and Aspergillus species.The essential oils were characterized by high percentage of α-pinene (75.5 and 84.2%), which distinguish them from oils from other countries where α-pinene is usually present in lower percentages. Essential oils exhibited high antifungal activity against dermatophytes and Cryptococcus neoformans with MIC values ranging from 0.32–2.5 μl ml−1.These results support that essential oils from J. phoenicea berries may be useful in the treatment of dermatophytosis. Further studies should be stimulated in order to evaluate toxicity and optimal concentrations for clinical applications.

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Efforts have been made to predict the sensory profile of coffee samples by instrumental measurement results. The objective of the work was to evaluate the most important sensory attributes of coffee samples prepared from ground roasted coffee by electronic tongue and by sensory panel. Further aim was to predict the Arabica concentration and the main sensory attributes of the different coffee blends by electronic tongue and to analyze the sensitivity of the electronic tongue to the detection of poor quality coffee samples. Five coffee blends with known Arabica and Robusta concentration ratio, five commercially available coffee blends and a poor quality coffee were analyzed. The electronic tongue distinguished the coffee samples according to the Arabica and Robusta content. The sensory panel was able to discriminate the samples based on global aroma, bitterness and coffee aroma intensity (p < 0.01). The Arabica concentration was predicted from the electronic tongue results by PLS with close correlation and low prediction error. Models were developed to predict sensory attributes of the tested coffee samples from the results obtained by the electronic instrument.

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The content of potentially antioxidant, anticarcinogenic and antiallergic flavonoid aglycons, quercetin, kaempferol, myricetin, apigenin and luteolin of 45 fruits were determined by RP-HPLC with UV detection. Fresh and dried fruits were purchased in the local markets in Budapest at a period of their most frequent consumption. Total flavonoid content of fruits varied between 0–1000 mg kg –1, the average concentration was about 30 mg kg –1 fresh weight. Quercetin could be detected in most fruits, namely in apples, pear, plums, sweet and sour cherry and berries between 10–53 mg kg –1. Luteolin at a concentration of 20 mg kg –1 was found in melons, apples, kiwi and lemon. Myricetin was in detectable amount in redcurrant, and at very high concentration in some berry fruits (mulberry 453 mg kg –1, raspberry 540 mg kg –1, blackberry 636 mg kg –1, strawberry 994 mg kg –1), and in walnut (4565 mg kg –1). Kaempferol and apigenin were not found in the fruits investigated. None of the five flavonoids was found in some variety of grapes, in peach, pear, banana, orange, grapefruit and tangerine, in nuts such as almond, pistachio, nuts, and in dried fruits such as raisin, date, fig and prunes. These data provide a basis for the evaluation of the average daily intake of Hungarian population and for an epidemiological evaluation of health-promoting effects of flavonoids. __

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Recently several studies have focused on the antioxidant activity of lycopene such as quenching of singlet oxygen and scavenging of peroxyl radicals. These properties may play a role in the prevention of different cancer and heart diseases. Tomato is one of the most important sources of lycopene. The main information on the effect of environmental parameters on quality and health-retaining constituents of tomato fruit is mostly related to temperature (air- and fruit canopy temperature) and light effects that might provide a stress to the fruit. Nowadays little is know about the direct effect of elevated CO2.The aim of the present work was to evaluate the effects of elevated CO2 in Perspex open top chambers (OTC) on the lycopene content of tomato fruit.Experiments on the effects of elevated CO2 concentrations showed mixed results. In this work it was found that concentrations of lycopene in a fruit decreased significantly when elevated CO2 was used. Elevated nitrogen sources generated only slight, but not significant difference in the lycopene concentration of tomato fruit.

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Acta Alimentaria
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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Total polyphenol content and in vitro antioxidant properties were investigated in five lager and three dark beers. The average concentration of total polyphenols in lager and dark beers was 376 and 473 mg l -1, respectively. All samples exhibited strong hydrogen-donating property and reducing power in a concentration-dependent manner. Beers also showed copper(II)-chelating ability and antioxidant property in Randox TAS measurement. The differences of polyphenol content and antioxidant characteristics between lager and dark beers were statistically not different. Antioxidant properties were dependent on the total polyphenol content of beers. The concentration of polyphenols and antioxidant properties except for chelating ability of beers measured in the same in vitro test system was very similar to those characteristics of white wine, while the extent of chelating ability of beers showed similarity to that of red wines. Studies evaluating the relative benefits of wine versus beer versus spirits suggest that moderate consumption of any alcoholic beverage is associated with lower rates of cardiovascular disease. Although beers have antioxidant capacity like white wines with having half the alcoholic content of wines, beers should be good sources of antioxidant polyphenols, and moderate consumption as a part of a well-balanced diet cannot be criticised either medically or socially and may have a beneficial effect on reducing oxidative disorders.

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Acta Alimentaria
Authors: M. Croitoru, I. Fülöp, M. Ajtay, G. Dudutz, O. Crăciun, and M. Dogaru

To date, monosodium glutamate is the most used flavour enhancing food additive. Because high levels of glutamate are toxic to brain concerns appeared regarding the safe use of glutamate and there is a 10 g kg −1 concentration limit in foodstuff. A simple HPLC-UV method, based on a derivatization procedure with o -phthaldialdehyde, was developed for determination of glutamate in meat products, soup bases and vegetable concentrates. Even if our method is less sensitive than the HPLC-fluorescence ones widely available, it is able to measure amounts at least 200 times smaller than the maximum allowed one, has good reproducibility (CV under 2% for intraday and under 3% for interday determinations), linearity and accuracy. Less expensive HPLC systems are required and the formed derivative is very stable (at least 1 week), good separation is obtained with the less expensive 5 μm particle C 18 columns and methanol as organic phase. Concentration of free glutamate ranged between 0.14 g kg −1 in sausage without added glutamate to as high as 2.16 g kg −1 in a pork sausage. Concentration in vegetable mixes and soup bases were between 80–120 g kg −1 .

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The influence of three milling techniques (MT1: industrial roller-grinder, MT2: grain hammer crasher, and MT3: traditional millstone) and two baking methods (BM1: industrial oven, BM2: traditional ceramic stove heated by wood (log fire oven)) on mycotoxin deoxynivalenol (DON) and nivalenol (NIV) levels in bread were investigated. The DON and NIV concentrations in wheat grain, flour, and bread were analysed using high performance liquid chromatography with UV-detection methods. The 2 500 kg lot of wheat grain containing 1 400–1 900 μg kg −1 deoxynivalenol and 130–200 μg kg −1 nivalenol was divided into sub-lots which were processed to get three types of flour (F1: industrial bread flour, F2: industrial wholegrain flour and F3: traditional wholegrain flour). The concentrations of DON and NIV measured after milling the grain according to MT1 (yielding F1) amounted to 310–370 \g kg −1 and <50–70 μg kg t1 , respectively. After applying MT2 to the grain (yielding F2), the DON and NIV levels were measured to be 1 060–1 400 μg kg −1 and 60–87 μg kg −1 , respectively. Applying MT3 (yielding F3) produced a DON level of 1 100–1 770 μg kg 1 and a NIV level of 80–95 μg kg −1 . Six types of bread were baked from the three types of flour according to BM1 or BM2, and the mycotoxin levels were analysed. The average reduction in DON concentration after baking (70 min at 195–235 °C) was 47.2% for bread baked in the industrial oven and 48.7% for bread baked in the log fire oven. Concentrations of DON in bread prepared by the industrial MT1 were under the permitted limit of 500 μg kg −1 stated in EC (2006) regulation, despite the fact that the bread was baked from grains highly contaminated with mycotoxins. In the bread baked from traditional wholegrain flour, mycotoxin concentrations were higher (850–950 μg kg −1 ).

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