Food colorants are additives commonly used in foods and beverages to compensate for color loss during processing and exposure to light, air, moisture, and temperature variations. This study evaluates the prevalence of colorants in popular beverages on the local market, including those specifically marketed to children. The study analyzed labelling information from 162 samples of refreshing non-alcoholic beverages produced by 24 manufacturers. A total of 62% of the samples contained at least one type of food colorant. The highest prevalence was observed in energy drinks and syrups for refreshing non-alcoholic beverages (90% and 85% of samples, respectively), followed by fruit juice-based beverages (71%). The most commonly used colorants were E150d and E160a. Considering the concerns regarding the potential health effects of certain colorants and their high prevalence in beverages, measures should be taken to promote proper nutrition and healthy child development by reducing the intake of synthetic colorants.
Fruit brandy is an agricultural and food product obtained by alcoholic fermentation and distillation of fermented fruit pulp. Plum as a fruit, is a raw material which is suitable for the production of brandy and the most commonly used variety of fruit. The aim of this study was to analyze physico-chemical properties od 12 brandies produced in the Republic of Srpska, during the 2020 year. Content of methanol, ethanol and HCN were in accordance with the current legislation, with significant mutual differences between the samples. The results of experiment show that there are significant differences in the quality of brandy, depending on the technological production process. To achieve more uniform quality it would be necessary to standardize brandy production.
Cefazolin sorption on oxidized cellulose was performed with the aim of obtaining biologically active fibers which, as drug carriers, have a possibility of prolonged release and local application. Oxidized cellulose with 0.555, 1.464 and 2.276 mmolg-1 COOH group was obtained by selective oxidation with a mixture of HNO3-H3PO4-NaNO2. Antibiotic water solution (c=3,4∙10-3 molL-1, t=20±1 °C) and physiological solution were used for bonding and desorption, respectively. Maximum amount of the bound drug (0,0337 mmolg-1) was obtained during the sorption on the oxicellulose with 2,276 mmolg-1 COOH and the maximum amount of the released drug was 0,0091 mmolg-1. Drugs sorption on the oxidized cellulose is accomplished through hydrophobic interactions. Disc diffusion test was used for determination of antimicrobial activity Staphylococcus aureus, Bacillus subtilis and Escherichia coli.
Environmental engineering is an interdisciplinary science that relies on the knowledge of a number of other "basic" sciences - chemistry, mathematics, physics, biology and geology. It focuses on designing processes and infrastructure for water supply, waste management, and the control of various forms of pollution. These initiatives safeguard public health by halting the spread of diseases and maintaining environmental integrity by preventing the contamination and deterioration of air, water, and soil resources In order to more easily cope with the challenges of environmental engineering as a science, future engineers must familiarize themselves with some basic concepts of geology, such as origin and structure of the Earth, plate tectonics, types of minerals and rocks, hydrological cycle and groundwater, endodynamic and exodynamic processes, formation and characteristics of the soil and climate changes. Acquiring knowledge from geology is an indivisible part of the education of every good environmental engineer, because they facilitate the distinction between natural and anthropogenic influences on the environment and direct them towards finding better solutions to environmental problems.
The paper presents an examination of the possibility of applying wild raspberry fruit extract as a green inhibitor of general corrosion of brass in 3% NaCl. Wild raspberry fruits were collected from the Moševac near Maglaj city, Bosnia and Herzegovina. Wild raspberry fruit extract was obtained by ultrasonic method. Results obtained by DC techniques (by the methods of Tafel extrapolation and linear polarization) prove that the corrosion rate decreases in the presence of the wild raspberry fruit extract. Tests performed by the method of electrochemical impedance spectroscopy prove that the tested extracts slow down the kinetics of the corrosion process, which is visible through the increase in resistance. The results of the conducted tests prove that in an aggressive medium, such as 3% NaCl solution, wild raspberry fruit extract can be used as an inhibitor of brass corrosion in concentracion of 0.04828 g/L.
New orange and magenta dyes, containing a residue of 4,4`-diaminostilbene-2,2`-disulphonic acid and allylic groups in their molecule have been synthesized. They were evaluated for applicability on cotton, and samples with intensive colour have been obtained. The degree of exhaustion, fixation and the optical properties from the CIE Lab colour space have been examined. The photostability of the dye in solution and dyed textile material was determined. The possibilities for copolymerization of the dyes with acrylamide and acrylonitrile have been investigated and intensive coloured, stable on different solvents polyacrylamide and polyacrylonitrile have been obtained. From the obtained results it can be concluded that the synthesized dyes are suitable for colouration of cotton and polymer materials as well as giving them UV protective properties.
Knowledge of the coordination chemistry of 2,6-diacetylpyridine-bis(phenylhydrazone) (L) is limited, and this compound seems promising in many fields. We explored the reaction of methanolic solutions of chromium(III) nitrate and L in a 1:1 molar ratio and obtained the thin red crystals of the complex. It was characterized by FTIR, elemental analysis, and molar conductivity. Comparing the ligand and the complex spectra confirmed that coordination has occurred through azomethine and pyridine nitrogen atoms. Molar conductivity of DMF solution indicates that the complex is an electrolyte of the type 1:1. The chromium(III) is most likely situated in an octahedral environment of six nitrogen atoms of the two ligand anions, viz. [Cr(L–H)2]NO3. These findings enable the further investigation of the complex properties. Besides, future research will explore the impact of changing synthetic conditions on the reaction product and their characterization.
The Erasmus+ project Edu4PlastiCircular addresses plastic waste and its role in achieving a circular, climate-neutral economy by fostering green skills in higher education. It focuses on developing training on key topics covering areas like: plastic world, waste management, circular economy, innovation, and responsible behavior. A gap analysis conducted at the Faculty of Environmental Protection and partner institutions assessed the knowledge and perceived usefulness of these topics. Both students and staff rated the topics’ usefulness higher than their current knowledge, with staff scoring both aspects more favorably. In terms of learning preferences, hybrid learning is favored overall, with students leaning slightly more toward face-to-face formats, while online learning was the least popular. PowerPoint presentations were the most preferred learning material, while printed and digital books were less favored. These findings provide valuable insights for designing educational programs that align with the needs and preferences of both students and academic staff.
The rapid growth of industrial, agricultural, and urban areas, along with rising living standards, invariably results in an increase in the amount of solid, liquid, and gaseous waste elements in water. Because of the variety of hazards that recreational waters pose to human health and well-being, a thorough evaluation of the sources and relative importance of the resulting health effects is necessary. The testing of bathing water quality was conducted by determination of physical-chemical indicators at three locations in the lake Šoderica in Varaždin county. Lake Šoderica is an artificial lake formed by quarries and also used as a swimming area. The results demonstrated that the water was suitable for swimming and that all examined criteria agreed with the legislation. The results of the analyzed physical-chemical parameters show that the bathing water is satisfactory, but it is also necessary to determine the microbiological parameters.
Wastewater from the textile industry is a complex mixture of many environmentally harmful substances such as unbound dyes and auxiliaries, pesticides, heavy metals and large quantities of salts associated with the dyes or the dyeing process. To reduce the wastewater load, action can be taken in two directions - firstly, by changing the charge of the cotton fibers to remove salts from the bath and increase the dye yield, and secondly, by producing filters for wastewater treatment. In the interest of sustainability, this article collects the possibilities of using cationized cotton during the mercerization process for this purpose. The results of zeta potential and coloristic parameters confirmed that the cationizated bleached and recycled cotton waste during the mercerization can be used in dyeing and printing without electrolyte, as well as filter for first step in water treatment.
Zeolite 13X is one of the best adsorbents among zeolites and one of the most commercially available zeolites. This paper investigates the influence of several process parameters on the properties of 13X zeolite, including crystallization temperature, crystallization duration and Si/Al molar ratio in the starting reaction mixture. The quality of the obtained powders was examined in detail through a series of analytical and instrumental methods, presented in the paper. Water and CO2 adsorption capacities were determined as key quality parameters of 13X zeolite, and additional characterization was performed by determining material granulometry, specific surface area (BET analysis), crystallinity (X-ray diffraction method) as well and SEM analysis. The obtained results indicate a clear dependence between the examined process parameters of the system and the characteristics of the synthesized materials, thus enabling the selection of optimal conditions for the synthesis of 13X zeolite.
Wild chicory and its cultivar `Zuccherina di Trieste` were grown in organic garden. The samples were taken from young leaf rosettes. A slightly higher concentracion of observed elements was found in wild chicory leaves, in relation to the leaves of the cultivar `Zuccherina di Trieste`. Wild chicory leaves also contain more moisture (87.28%), cellulose (2.23%) and vitamin C (6.52 mg/100g) compared to the leaves of the cultivar (84.77%, 2.196% and 3.93 mg/100g, respectively). When it comes to phytochemicals, leaves of the cultivar predominate in total phenols (2.49 mg GAE/g) and lag behind in total flavonoids (0.94 mg Qc/g) and flavonols (1.00 mg Qc/g) compared to the leaves of wild chicory (1.74 mg GAE/g, 1.21 mg Qc/g and 1.66 mg Qc/g, respectively). Fresh leaves of the cultivar showed significantly stronger antioxidant activity, compared to fresh leaves of wild chicory.
Cheese is a dairy product used directly for human consumption or indirectly as an ingredient of other foods or ready meals. Being an extremely valued product, cheese is a concentrated source of proteins, vitamins and minerals, especially calcium, phosphorus and magnesium. Various spices are used to enhance the taste of food, which also have numerous medicinal properties. The aim of this study was to examine the effect of the addition of different spices on the mineral composition of cheeses, obtained by heat-acid coagulation of milk. There were six different samples of cheese produced in the milk processing plant (mini cheese factory). The first sample was taken as a control one, with no addition of spices, and the other five were produced with 0.5% addition of different spices (oregano, basil, parsley, rosemary, and chives). The total ash content and the content of macro- and microelements were determined in the tested cheese samples. It was established that the addition of different spices has a statistically significant (p<0.05) effect on the content of macro- and microelements in the produced cheeses. The total content of macro-elements ranged from 612.55 mg/100g to 811.81 mg/100g, of which sodium had the largest share (from 293.61 mg/100g to 389.20 mg/100g), as well as calcium (from 74.13 mg/ 100g to 278.12 mg/100g). The total content of microelements in the tested spice-containing cheeses ranged from 7.317 mg/100g to 9.360 mg/100g, of which the most abundant was zinc, the content of which was between 5.903 mg/100g and 7.351 mg/100g.
Knowledge of the weed flora of a certain area, as well as knowledge of the relationship between cultivated plants and weed plants, is important for successful weed control and the efficient application of agrotechnical measures. The aim of this paper is to provide an overview of the weed flora in maize fields in the area of Novi Grad, as well as a taxonomic analysis, an analysis of the biological spectrum, a phytogeographical analysis and an analysis of ecological indicators of the maize weed flora. During field research on two maize fields in the area of Donji Rakani village (Novi Grad), a total of 38 species of vascular plants were collected, which were systematized into 35 genera and 16 families. The most abundant in terms of species numbers were the families Compositae (31.58%) and Poaceae (18.42%), as well as the genera Erigeron, Ranunculus and Setaria. Hemicryptophytes (36.84%) and therophytes (31.58%) dominated the biological spectrum. Phytogeographical analysis revealed the dominance of the Eurasian (25.81%) floral element. A total of seven adventive species were recorded. The paper also presents the results of the analysis of ecological indicators for soil moisture, soil reaction, nutrients, light and temperature. The results of our research contribute to a better knowledge of the weed flora in maize fields, which could be useful for creating more efficient weed control measures.
Maintaining the quality of drinking water is the basis for the prevention and control of waterborne diseases. Due to the possibility of the presence of various pollutants in water, drinking water preparation at the point of its use is growing rapidly. All this leads to the intensive production of household water purification systems for preparing drinking water or correcting tap water composition if there is any doubt about its quality. The goal of this work is to estimate the efficiency of a home water filter for water purification, the “Brita system”, as well as its capacity, during practical use for different types of water (drinking water and spring water). Filtration of water through the "Brita" filter results in quite uneven values of the tested water quality parameters, although these same values are quite uniform in unfiltered samples. This is precisely why it happens that certain quality parameters do not meet the values given by Regulation (pH value, concentration of ammonium ion and orthophosphate ion) at the beginning of the filter use. The occasional appearance of nitrite ion depends on the dynamics of filter use. Therefore, it is recommended to use the "Brita" filter continuously after its activation. The removal efficiency of iron (60-90 %) and aluminum (> 90 %) from water is very effective even after 100 dm3 is passed through the filter. Due to the active carbon granules present in the filter, the removal of trihalomethanes is also very successful.
The adsorption process gives great results for the removal of different types of colored substances or different, mainly organic pollutants from wastewater. In addition to standard adsorbents (such as activated carbon), cheap and natural adsorbents have been increasingly used in recent times (e.g. clay, zeolites), along with waste materials (fly ash from thermal power plants or different agricultural/plant remains), after proper preparation and modification. Research presented in this article was performed with fly ash from thermal power plant Stanari. The aim of this study was to investigate the possibility of removing Bemacid Red (BR) dye from textile industry wastewater by adsorption on fly ash modified with HCl. After a series of experiments, the optimal process parameters were determined. These parameters were then applied to a wastewater sample obtained by simulating polyamide fabric dyeing. The efficiency of adsorption of BR dyes from aqueous solutions depends directly on the process parameters: contact time, pH value, adsorbent dose and initial adsorbate concentration (dye concentration). Under optimal process conditions, a dye removal rate of 97.1 % was achieved. Analyzing the experimentally obtained data using nonlinear adsorption isotherms, a much better agreement of the Freundlich model with the experimental results was determined (the coefficient of determination is R2=0.9787). The obtained data show that the adsorption of Bemacid Red dye on fly ash is multilayered. Optimal parameters of the adsorption process were applied to wastewater obtained by simulating the process of dyeing polyamide fabric with BR dye. The efficiency of adsorption under defined conditions was confirmed through the 100 % removal of dye from a real wastewater sample.
Flax fibers contain cellulose and different impurities (hemicelluloses, lignin, pectin, waxes and fats, mineral salts, natural coloring matter and water soluble compounds). From the ecological and industrial aspect, hydrogen peroxide is the most acceptable component for modification of flax fibers. The aim of the modification of flax fibers is to remove non-cellulose components and improve the fiber quality without significant changing of the mechanical properties. Flax fibers were treated with hydrogen peroxide solutions at concentrations 1%, 2% and 4% at 50 °C, 80 °C and boiling temperature for time period of 60 min. With the removal of non-cellulosic substances from fibers, it has been achieved a high degree of fiber separation and a significant increase of modified fibers fineness. The value for fineness of modified fibers was reduced about 2-4-fold and the modified flax fibers were softer to the hand, unlike unmodified fibers that are very coarse and stiff. However, the weight loss and removal of lignin, which gives the fibers strength, as well as a partial damage of the cellulose itself during the severity of treatment, brought to reduction in the tensile strength of the modified fibers.
The aim of this research was to determine the effect of buckwheat flour addition on the selected quality parameters of nutritive enriched wheat scones. Wholegrain buckwheat flour was used to subsitute 15%, 30% and 45% of white wheat flour to produce buckwheat enriched wheat scones. The dough for scone making was prepared from a mixture of wheat and buckwheat flour with the addition of salt, yeast, mixture of additives and water. Proximate composition and sensory evaluation of buckwheat enriched wheat scones were analyzed and compared. Descriptive sensory analysis of scones was conducted evaluating the following sensory properties: shape and volume, external appearance, appearance of crumb (cross-section), taste and flavor of crust and crumb. All results of descriptive sensory evaluation were presented as percentage from maximum possible quality (100%), and were in interval of 77.63%-91.41%, indicating that two samples of scones (produced with 15% and 30% of buckwheat flour) had excellent and very good quality, and only scone sample produced with 45% of buckwheat flour, had good quality, but relatively low for placement on market. Based on the results, it can be concluded that wheat flour scones enriched with wholegrain buckwheat flour up to 30%, have excellent or very good technological and sensory quality.
Sludge generated in wastewater treatment processes must be treated in an adequate manner, and therefore disposed of in an environmentally friendly manner. The biggest obstacle to the efficient use of sludge is the high water content, therefore the development of methods to accelerate the sludge dewatering process is particularly important. For the purposes of the research, the waste sludge created in the process of purifying ammoniaphenol wastewater in the GIKIL factory was used. Sludge conditioning was performed by adding a commercial flocculant (0.1 % solution) in combination with pyrophyllite, kaolin clay and shredded cardboard. According to earlier research, the volume of waste sludge with the addition of a suitable flocculant could be reduced by more than 5 times compared to the initial amount, leaving behind a large amount of separated water that can be returned to the process. The results show that the addition of commercial flocculant in the amount of 0.8 % gives the best results (reduction of sludge volume by 78.8 %). A lower percentage was found in samples with a mixture of flocculants with pyrophyllite (78 %) and kaolin (77.6 %), while the combination of flocculants with waste cardboard was ineffective (64.4 %). Addition of flocculant to waste sludge resulted in a decrease in specific filtration resistance (1.15x107 s2/g). A decrease in specific resistance was also observed in flocculant/kaolin clay (0.8x107 s2/g) and flocculant/cardboard (1.09x107 s2/g) samples. Sludge conditioning also resulted in a reduction of suspended solids in the neonate compared to settled raw sludge without additives.
Due to the limited availability of wood, as the highest quality raw material for the production of biomass pellets, increasing attention is being paid to the production and use of pellets from low-quality materials such as different types of agricultural waste. However, the complex chemical composition of these types of biomass often leads to various problems during their combustion. One of the biggest problems when it comes to burning biomass pellets is related to the low melting temperature of the resulting ash and its tendency to sintering. By modifying the chemical composition of biomass, it is possible to influence the method of combustion and the characteristics of residual ash. Modification of biomass composition can be carried out by chemical pretreatment with acids, which reduces the concentration of alkali metals and alleviates ash adhesion and the tendency to form slag. Pellets made from wood biomass, soy straw and chamomile waste from the process of processing medicinal plants were used for the tests in this work. Chemical pretreatment, which consisted in washing the pellet samples with a diluted solution of hydrochloric acid, resulted in mass loss in all cases. The amount of ash, after treatment in hydrochloric acid solution, was reduced by 72.15% -93.27%, depending on the concentration of acid and the type of biomass
