Summary We analyzed heavy metals content and magnetic susceptibility (χ) of urban soils sampled in Chernivtsi city (Ukraine). X vary from 10*10−8 to 1286*10−8 m3/kg with a median value of 66* 10−8 m3/kg. In 20% of samples χ exceeds the median value three times or more, indicating that the soil is contaminated with iron dust and magnetic particulate matter derived from anthropogenic aerosols. It was found that the priority pollutants of urban soils are Pb and Zn, the content of which exceeds the critical concentrations in the vast majority of samples. The maps were composed, showing spatial distribution of χ and Pollution Load Index (PLI), calculated by three metals (Zn, Pb, and Cu). For 51% of the samples, the PLI value indicates no contamination, for 35 % – moderate contamination level, 14 % – very strong soil contamination.
Global trends of promoting a healthy lifestyle through a balanced diet and reducing the consumption of animal products and high-fat-content foods have contributed to the creation of new mayonnaise-like products. The aim of the study was to develop a technology for low-fat mayonnaise containing 30% sunflower oil. Canned white bean aquafaba was used as a plant-based emulsifier to create an egg-free sauce. To maintain the texture and rheological properties of the food emulsion, a water-soluble polymer such as carboxymethylcellulose was used as a thickener and a pectin–xanthan mixture was used as a gelling agent. The ratio of the main ingredients of the emulsion emulsifier/stabilizer/thickener was 3:0.7:0.3 (%). The prepared emulsion-like sauce was characterized by high sedimentation stability at the level of 98%, as well as acidity equal to 0.691 g of acetic acid equivalent per 100 g sample and pH = 3.66. The volume droplet size distribution had a mean particle size of 8.4 μm and a SPAN factor of 1.7 µm, indicating typical values for these parameters of a well-homogenized mayonnaise-like emulsion. Rheological studies made it possible to classify the samples as viscoelastic systems with a pseudoplastic flow pattern and a sufficiently high yield shear stress value equal to 132 Pa as a quantitative parameter confirming the stability of the microstructure over time. Sensory analysis confirmed high scores for consistency, taste and smell of the end-product.
The present paper analyzes the efficiency of various mineral fining agents (nano dispersion composites SiO 2 , TiO 2 , TiO 2 -SiO 2 , bentonite and saponite) in the process of white and red wines fining. The influence of both the mass of the adsorbent and the time of the storage in wine on the optical density of wine was investigated.The best results were obtained with TiO 2 , AMD-2 and SiO 2 for white wines, and bentonite and AMD-2 – for red ones. It was shown that the optimal time of contact for wine with the fining agent is: four days - for white wines and two days for red ones.
The results of long-term observations on the geochemical peculiarities of technogenic lead distribution in atmospheric aerosol of Zaporizhia, as well as in soils, bottom sediments, suspended matter from Dnipro river and substance from wet gas filters of open-hearth furnaces PJSC Zaporizhstal are presented. The actual material was obtained on the basis of comprehensive field monitoring during 2015-2019. Simultaneous involvement of data on hydrometeorological conditions (seasonality, precipitation, wind speeds, directions and duration) in the study area provided a integral approach to the processing and generalization of research results. A number of peculiarities of sedimentary substance distribution in air, interrelations of its anthropogenic and natural components are defined. Correlations were revealed between lead concentrations changes and aeolian mineral component distribution, seasonality, and a number of other factors. The highest concentration of lead was found in solid aerosol particles accumulated by the sedimentary trap at the monitoring site. It was revealed that the average concentration of investigated element in river suspension of Dnipro exceeds significantly background values, and for soils exceeds more than 3.5 times the permissible norms. At the same time, the fixed form of lead in atmospheric aerosol, in contrast to other environmental objects, loses its domination, giving the way to easily soluble forms, so the evidence of environmental hazard. Monitoring of seasonal patterns of the element distribution in the city air showed excess concentrations in the cold period of the year, which, according to the authors, is due to both meteorological conditions and redistribution of natural and anthropogenic factors that serve the driving force in processes of arriving and conversion of lead in atmosphere during different seasons of the year.
Introduction.The aim of presented work was the investigation of the efficiency of clarification of direct pressing apple juice with utilization of nano-sized powders of both silicon dioxide and titanium dioxide, modified silicon dioxide powder in comparison with bentonite clay.Materials and methods.The juice used for laboratory testing was squeezed from "Glory to the Winners" apples.Modified silicon dioxide powder (AMD-2, specific surface area 280 m 2 /g) and nanodispersed powders of both silicon dioxide (specific surface area 300 m 2 /g) and titanium dioxide (specific surface area 50 m 2 /g) were selected as clarifiers.For comparison, we used bentonite clay (specific surface area 160 m 2 /g).The optical density was measured with spectrophotometr, the content of dry substances was evaluated refractometrically, pH and titratable acidity was determined according to known methods.Results and discussion.Prospects of mineral oxides of titanium and silicon utilization for clarification of apple juice have been shown.It was established that the most effective clarifiers were SiO2 powder and suspension.Optimal weight of SiO2 is 2.5 g per 1 liter of juice; steep time is not more than 24 hours.The form (in powder or suspension) has no significant effect on the result of clarification.The worst clarification ability bentonite clay demonstrated.It was confirmed that utilization bentonite in suspension form increases the clarification efficiency.Growth a mass of bentonite from 0.1 to 2.5 g per l of juice impairs its optical properties.The effect of temperature of clarification processes on its efficiency and influence of the "juice-clarifier" contact time on the physical-chemical properties of the finished product were investigated.It was shown that the result of clarification is better at low temperature (4 ºС), and all the used oxides are able to slow down the flow of natural processes of fermentation of raw apple materials.It was found that more than 24 hours contact of juice with clarifiers has a negative influence on the clarification result for all tested samples.Conclusion.Nano-dispersed oxides of titanium (IV) and silicon (IV) could be effectively utilized to clarify of fresh direct pressing apple juice.Their clarifying ability is higher than bentonite clay and they could be brought in juice without pre-treatment, in the form of powder.
Metallurgical industries incorporated into the living environment of the city cause significant enrichment of the topsoil with harmful substances including small size particulate matter, which contains heavy metals and magnetic iron oxides. The present study is focused on characterization of magnetic and geochemical pollution accumulated by urban soils in the city of Zaporizhzhia. Industrial dusts from the most powerful emmitants of airborne pollution are also analyzed. The aim of the study was to conduct magnetic and geochemical characterization of soils in Zaporizhzhia as a pre-war reference point. This characterization will serve as a baseline for comparison in future studies investigating changes in pollution rates resulting from the war situation that began in 2022. Magnetic measurements, determination of concentrations of heavy metals (HM) and electron microscopy and granulometry investigations were performed to characterize the technogenic magnetic phases in industrial dusts collected in chimneys and filters. The magnetic mineralogy of dusts and soils is deduced from temperature behavior of magnetic susceptibility. We access the spreading of magnetic pollution over the topsoil of the city and investigated statistical correlations between magnetic properties and contents of HM...
A significant number of foods are manufactured in the form of emulsions. A typical example of such a product is mayonnaises, which vary in oil content. However, as a macroemulsion, they are a thermodynamically unstable system. Therefore, the physical instability associated with processes such as flocculation, coalescence and Ostwald ripening leads to separation of the oil and water phases over time. This is especially typical of low-fat mayonnaises. As the oil content in the sauce decreases, it is necessary to add various biopolymers to ensure its stability over time. Predicting physical instability is important for food technology development purposes, and especially for reduced oil systems as the most challenging task in terms of system stabilization. In the first approximation according to the Stoke's model, the stability of an emulsion is affected by microstructural characteristics such as as the droplet size and the rheological properties of the emulsions. The combination of this approximation with the generalized Casson's rheological model for structured liquid systems allows us to propose an approach for estimating the rate of emulsion creaming. The parameters used for calculations are determined from rheology and laser diffraction data for mayonnaise samples. The approach is devoid of empirical variables, since all parameters have a physical meaning on the basis of the kinetic model of destruction–recovery of the structural aggregates of the system. Calculations were carried out for a series of commercial mayonnaises (CMs) and developed low-fat mayonnaise (LFM). The results make it possible to evaluate the physical stability of emulsions, as well as the influence of rheological and microstructural characteristics on the texture of the final product during its shelf life.
