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Az azbesztszálak kimutatására szolgáló vizsgálatok középpontjában a levegőszennyezettségi értékek álltak, de a 21. században felmerült az igény a problémakör kiterjesztésére. Az elmúlt években megjelent nemzetközi tudományos szakirodalmak megcáfolták az évtizedeken át fennálló feltételezést, miszerint az azbeszt csupán a levegőterheltség révén vált ki kockázatot. Vízminőségi és talajminőségi kutatások által teret nyert az azbesztszálak, különösen a krizotilszálak alternatív transzportútjainak vizsgálatát célzó kutatásterület. Annak ellenére, hogy mind a települési, mind pedig a mezőgazdasági vízgazdálkodás potenciálisan érintett a krizotil-azbeszt jelenléte kapcsán, nincs nemzetközi szinten egységes és elfogadott módszer vagy küszöbérték az egyes vízforrások biztonságára vonatkozóan. A kutatások nyilvánvaló korlátja, hogy csekély mennyiségű és minőségű tudás érhető el. Az azbesztszálak megjelenése az egyes vízbázisokban jelentősen megváltoztatja mind a mezőgazdasági, mind a települési vízgazdálkodás környezeti hatásoknak való kitettségéről alkotott eddigi ismereteinket. Az öntözővizzel és a gyűjtött csapadékkal kijuttatott azbesztszálak hatásainak palettája mára túlhaladta a humán- és állategészségügyi hatásokat, immár figyelmet kell fordítani a vegetációs hatásokra is. Annak érdekében, hogy nagyobb betekintést nyerjünk az azbeszttoxicitás növényekre gyakorolt hatásaiba, sokkal több tudományos eredményre van szükség.
Jelen összefoglaló tanulmányban bemutatjuk az azbeszt, különös tekintettel a krizotil azbeszt legfontosabb tulajdonságait, humán-, állat- és növényegészségügyi kockázatait. Rávilágítunk arra, hogy ismereteink rendkívül hiányosak, valamint felhívjuk a figyelmet a települési és mezőgazdasági vízgazdálkodás érintettségének egyes faktoraira, közvetlen és közvetett kockázati tényezőire, valamint arra, hogy ezek miként hatnak az élőlényekre, kiemelt tekintettel a növényekre.
Abstract
Oxygen plays a crucial role in all stages of wine production. The aim of this study was to quantify dissolved oxygen in filtered wines trained on fine lees during different technological operations such as racking, coarse filtration, stabilisation of thermolabile proteins, and sterile filtration and bottling. The most significant oxygenation of wine occurs during filtration (1.9–3.57 mg L−1) and during bottling (2.99–4.12 mg L−1). At the same time, oxygen affects the phenolic composition, antioxidant activity and sulphur dioxide.
Understanding and being able to use oxygen correctly during wine production can lead to a reduction in the doses of sulphur dioxide used. It has been shown that wines trained on fine lees are more able to withstand oxygen and, therefore, the sulphur dioxide doses can be reduced substantially. The experiment, in which two different winemaking technologies were observed, was carried out on the Welschriesling variety using both stainless steel tanks and oak barrels.
Abstract
This work explored the impact of mixed flow spray drying on the physical and functional properties of whey powder without any subsequently added drying agent to increase whey utilisation. Spray drying was performed on a pilot scale using a mixed flow spray dryer. The effects of the inlet air temperature (150–210 °C) and feed flow rate (2–7 L h−1) on several responses such as moisture content, yield, dispersibility, bulk density, and outlet air temperature were investigated using response surface methodology. In addition, with the optimised parameters, Carr index, Hausner ratio, solubility, wettability, hygroscopicity, degree of caking, crystallinity, and morphology of the obtained whey powder were determined. The investigation revealed that feed flow rate is the main parameter influencing all responses. The inlet air temperature significantly affected the bulk, tapped density, and outlet air temperature. The optimal inlet air temperature and feed flow rate for the production of whey powder were 182 °C and 3.2 L h−1, respectively. Under these parameters the moisture content, yield, bulk density, hygroscopicity, and degree of caking of the obtained product were 28.6, 1.80%, 0.24 g cm−3, 16.10 g H2O/g powder, and 85.56%, respectively.
Abstract
Membrane filtration has a promising advantage in the processing of egg products. In this study, liquid egg whites (LEW) were separately concentrated by using reverse osmosis (RO) and ultrafiltration (UF) techniques. The first aim of this research was to determine the effects of the concentration pre-treatments on the physico-chemical quality criteria (pH, relative whipping capacity, foaming stability, water holding capacity-WHC, colour) and the rheological behaviour (viscosity, oscillation) of LEW samples. The second aim of this research was to investigate the impact of the membrane pre-treatment on meringue's functional quality attributes such as meringue batter density and meringue batter colour values (L*, a*, b*). The average dry matter of LEW was increased from 12% to 23% by the concentration pre-treatment process (RO and UF), and water was removed from the LEW. In addition, the batter density of meringue cookie samples was 0.37 ± 0.01 g mL−1 in UF and RO. The differences between the pH and dry matter values of the ultrafiltration and reverse osmosis treated groups were found to be statistically similar, and it was observed that the elastic modulus (G′) increased with the increase in frequency in the rheological measurements. It has been determined that G′ is higher than G″ in all samples. An elastic/solid-like (G′ > G″) structural behaviour was determined while increasing the frequency value. It was determined that the WHC of LEW treated with RO was higher than of the group treated with UF. The results of the study showed that while reducing transportation and storage costs, the water content of >80% of LEW (raw material-the treated liquid egg white) removed by UF and RO applications can be suitable to produce meringue batter cookies (semi-finished product).
Abstract
For a long time, olive oil has been considered for formulation of biopharmaceuticals and received a prestigious place in cuisine for its unique organoleptic and nutritional properties. Nevertheless, oxidation of fatty acids in olive oil provides short shelf-life and undesirable organoleptic properties. Thus, microencapsulation of olive oil is a considerable promising approach to maintain its quality and biological activities. The objective of this investigation was to prepare extra virgin olive oil microcapsule by sequential technologies, such as water emulsification of olive oil with wall material (matrix) and freeze drying of emulsion. The effect of wall material composition was examined to prepare microcapsule of extra virgin olive oil. Different ratios of wall materials such as maltodextrin (MD), carboxymethyl cellulose (CMC), and gum arabic (GA) were used. Furthermore, effects of emulsification technologies, such as homogenisation with rotor–stator homogeniser (RSH) and cross-flow membrane emulsification (CFME) were investigated. The stability of emulsion was higher when emulsion was prepared by RSH; however, the droplet mean diameter (D32) was lower in case of RSH compared to CFME. The highest encapsulation efficiency (EE) was found as 68.96 ± 2.6% when CFME was adopted and composition of wall materials was 15 g MD, 15 g GA, and 5 g CMC.
Abstract
Rye is an important raw material of bread due to tradition and its favourable nutritional and technological qualities. Despite the beneficial fibre composition, a special group of short-chain carbohydrates, the so called FODMAPs (fermentable oligo-, di-, monosaccharides and polyols) may cause problems for patients with irritable bowel syndrome. The aim of our work was to investigate the non-starch carbohydrate (dietary fibre compounds, short-chain carbohydrates) composition of rye varieties, and of their novel milling fractions obtained from industrial milling trials and test loaves made from them. Regarding fibre and short chain carbohydrate composition, rye varieties did not show significant differences. In new subfractions, fibre and FODMAP composition were described, among profiles most of them differ from commonly used flours, independently from variety. The yeast fermentation and baking caused a decrease in water-extractable arabinoxylan content, at the same time increased the substitution pattern of water-extractable arabinoxylans. Furthermore, breadmaking process decreased the fructan content, and therefore increased the fructose level, thus modifying the short-chain carbohydrate composition. Based on our knowledge, this research is among the first ones investigating the fibre and short-chain composition of rye from the seeds to the consumable final products.
Abstract
Coatings of rice flour (RF), reinforced or not with rosemary essential oil (ROS), were used to evaluate changes in the internal quality of quail eggs stored at room temperature. Quality parameters [egg weight loss (EWL, %), Haugh unit (HU), yolk index (YI), albumen and yolk pH], microbiological (counts of total aerobic mesophilic bacteria and Enterobacteriaceae) and sensory (colour, aroma, odour, texture, taste, and general acceptability) parameters were evaluated during the experiment. Compared to the number of total aerobic mesophilic bacteria on the shell of uncoated eggs (2.02 ± 0.49; 1.78 ± 0.20 log10 CFU mL−1), RF/ROS exhibited significant inhibition effects for these bacteria on 0. (1.16 ± 0.25 log10 CFU mL−1) and 21. (0.84 ± 0.11 log10 CFU mL−1) days of storage at room temperature. On days 7, 14, and 21, RF had no effect on HU (P > 0.05), but eggs coated with RF/ROS had significantly higher HU (P < 0.05) than uncoated eggs from day 14, maintaining grade AA (73.88 ± 2.67) on day 21, while uncoated eggs had grade A (68.90 ± 1.55) at that time. The RF coating reinforced with ROS was a bioactive, efficient, and safe formulation for application based on internal quality, microbiological and sensorial aspects of quail eggs.
Abstract
The present study evaluated the effect of winemaking technologies on the concentration of different biogenic amines in Chardonnay wines. Wines produced from sedimented, inoculated must with active dry yeast without malolactic fermentation were compared with wine produced from nonsedimented must spontaneously fermented with malolactic fermentation. Histamine and putrescine concentrations were not significantly different in either variant. The highest concentration of histamine was 0.055 mg L−1, and the highest concentration of putrescine was 1.6 mg L−1 in both variants. Statistically significantly higher values of cadaverine (from 0.06 to 0.07 mg L−1), spermidine (from 0.8 to 1.4 mg L−1), spermine (from 0.15 to 0.25 mg L−1), and isoamylamine (from 0.40 to 0.46 mg L−1) were found in the variant made from nonsedimented must, in which spontaneous malolactic fermentation was performed. The higher concentration of biogenic amines in this variant may be due to the different composition of lactic bacteria during the spontaneous malolactic fermentation. A simplified, unpublished HILIC method of chromatographic separation of biogenic amines without prior deprivation with MS-MS detection was used to determine individual biogenic amines.
