Technologica Acta - Scientific/professional journal of chemistry and technology

Editorial: A Vignette on the 65th Anniversary of the Faculty of Technology

Sabina Begić — Fri, 08 Nov 2024 00:00:00 +0100

A Vignette on the 65th Anniversary of the Faculty of Technology and the Dean's Address to the 2024/2025 Freshman Class

The content of heavy metals in honey as indicators of pollutants

Selma Kunic, Tijana Brcina, Ramzija Cvrk — Fri, 08 Nov 2024 00:00:00 +0100

Honey and honeydew are natural foods with a very complex composition that contain both, organic and inorganic ingredients. Regardless of the progress of the industry, it can't be replaced by some production process.

The quality of honey varies from year to year, and bees can never produce the same honey and honeydew. Weather conditions, grazing, treatment of bees, proximity to industry, roads, etc., greatly affect the quality of the obtained honey. Although minerals and heavy metals are minor constituents of honey, they play a vital role in determining its quality.

The goal of the research is to assess the qualitative status of honey based on the content of contaminants, heavy metals from the area of the Tuzla Canton. The research was conducted on 30 (thirty) honey samples. The samples were collected in the period September/October 2022 and constitute the grazing of the specified year.

In the samples that were the subject of research, As and Cd did not exceed the limit of quantification (LOQ = 0.009 mg/kg). Current regulations does not define MRL’s for these two metals. As for the quantified amount of lead (Pb), it was the same in 12 samples and in 11 samples there was an evident deviation from the MRL. The measured lead (Pb), values range from 0.06 to 5.34 mg/kg.

The quality of bee products from the aspect of contamination with heavy metals can serve as bioindicator of environmental pollution, that is, as an indicator of the level of good beekeeping practices.

Dynamics of smoke ingredients penetration into the interior of chicken meat products during boiling/smoking and drying

Sebila Rekanović — Fri, 08 Nov 2024 00:00:00 +0100

During processing in meat, numerous activities occur. Those activities can have a positive or negative impact on the properties of aw materials and finished products. The aim of this study was to determine the dynamics of smoke components penetration (total phenols and organic acids) during boiling/smoking and drying of chicken meat at different thermal regimes. The dynamics of total phenol and total organic acids penetration into meat samples was monitored during all stages of production (cooking/smoking, drying and storage). Eight experimental groups were analyzed. Samples in four experimental groups (EG I-IV) were subjected to boiling and smoking, and other four groups (EG V-VIII) to drying with different parameter values: boiling/smoking temperature 55-75°C, process duration 80-110 minutes, drying temperature 14-18°C, with air circulation 40-50 m³/min and relative humidity 85-88% in appropriate conditions.

Based on the obtained results, the statistically significant influence of different heat treatments and their technological parameters on the dynamics of phenol and organic acid penetration was established (p<0.05). Temperature stood out as an important technological parameter with the greatest impact. The results show that due to elevated temperatures during heat treatments there is an increase in the concentration of total phenols and organic acids. Furthermore, it was concluded that the investigated processing procedures of chicken meat had an impact on the dynamics of penetration of smoke components.

Biocidal properties of CuO nanoparticles

Fri, 08 Nov 2024 00:00:00 +0100

Biocides are products used to prevent or control the spread of various harmful organisms such as bacteria or viruses. Silver and gold nanoparticles are mostly used as active substances of biocides used in the medical field. However, a more economically acceptable alternatives are different copper compounds, specifically copper(II) oxide. CuO nanoparticles were gained via sonication method from copper(II) acetate in a sodium hydroxide solution. Physical and chemical properties of gained CuO nanoparticles were investigated by X-ray diffraction analysis (XRD), energy dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA) and atomic force microscopy (AFM). Biocidal tests were performed on bacteria Pseudomonas aeruginosa and Bacillus subtilis, as well on fungi Candida albicans and Aspergillus niger using the disc diffusion method. The ultrasonic irradiation method was found to yield pure CuO nanoparticles smaller than 70 nm. Also, EDS measurement verified the stoichiometric distribution of copper and oxygen in the sample. Antimicrobial properties were proven excellent for both bacteria and fungi except for Pseudomonas aeruginosa, for which CuO nanoparticles seem to have low effect.

Extraction of oils from fruit kernels with conventional and innovative methods: a review

Fri, 08 Nov 2024 00:00:00 +0100

Over recent years, the food industry has striven to reduce waste, mostly because of rising awareness of the detrimental environmental impacts of food waste. While the edible oils market is enlarging constantly, there is increasing interest in producing plant-based oils because of the presence of various bioactive components like mono and poly unsaturated fatty acids. In recent publications it has been shown that various fruit kernels represent source of these components while the conversion of bio-waste into valuable compounds is of outmost importance for ensuring sustainability of the environment. This review investigates the different methods used for extraction of oils from sour cherry, peach, apricot and olive kernels and comparison between these methods in terms of extraction yield, fatty acids profile, tocopherols yield and antioxidant activity. An overview of chemical composition, bioactivity and on the application of these oils in end markets such as cosmetics, pharmaceuticals and nutraceuticals is presented. Scientific databases such as PubMed, Scopus, Google Scholar, Research Gate, ClinicalTrials have been used to assemble the data for this review.

Investigation of the catalytic activity of hydrated lime Ca(OH)2 in the process of transesterification of vegetable oils

Azra Halilović, Zoran Iličković, Sabina Begić, Amir Fazlić, Mugdin Imamović — Fri, 08 Nov 2024 00:00:00 +0100

Currently, humanity is facing two existential problems: the constant reduction of fossil fuel supplies, primarily crude oil, and global climate change, which is a direct consequence of the increasing use of fossil fuels both in industry and in the transport sector.[1,2] One of the possible solutions for these problems are biofuels, fuels obtained from renewable raw materials, as it is biodiesel [2], which attracted attention due to characteristics such as high degradability, non-toxicity and low emission of carbon monoxide, particulate matter and unburned hydrocarbons, as well as the possibility of being used either in a mixture with fossil with diesel or independently as 100% biodiesel fuel.[3,4,5,6] Heterogeneous catalysts in transesterification processes, i.e. biodiesel production, have been an area of significant and extensive research for many years. It is noticeable that there are significantly fewer works in which the application of Ca(OH)2, was investigated, and the published works show conflicting results, both in terms of its catalytic activity and in terms of the achieved yield of fatty acid methyl esters (FAME). The main goal of this work was to analyze the physico-chemical, chemical, mineralogical, morphological and surface characteristics of hydrated lime produced by Stamal Ltd. Kreševo, with the aim of examining the possibility of its application as a catalyst in the process of transesterification of vegetable oils. The obtained results unequivocally show that by using this hydrated lime as a catalyst in the transesterification process of rapeseed oil, it is possible to achieve a yield of methyl esters that meets the minimum limit of 96.5% prescribed by the European standard for biodiesel, EN 14214.

Optimization of liquid soap formulation

Fri, 08 Nov 2024 00:00:00 +0100

The quality of liquid soap for washing hands depends on its chemical composition, and it is evaluated by the physicochemical and functional characteristics of that product. The aim of the work is to optimize the formulation by varying the concentrations of anionic and amphoteric surfactants, as well as the concentration of the electrolyte-NaCl. As the concentrations of amphoteric and anionic surfactants in liquid soap increase, the values of density and viscosity increase. The value of the surface tension decreases with the increase in the concentration of the present surfactants, with the greater contribution to the decrease being shown by the anionic surfactant. Regardless of certain advantages that the anionic surfactant shows over the amphoteric one, the best characteristics of liquid soap are shown by the formulation that contains a combination of both used surfactants. The addition of NaCl to a liquid soap formulation has multiple significance, but also a different effect on the physicochemical characteristics at lower and higher concentrations. Functional and some physicochemical characteristics of liquid hand washing soap depend on the pH value of the formulation. As the pH value increases, the surface tension increases, so pH=5.5 is taken as the optimal pH value of liquid soap, as a compromise between the values of the measured characteristics and the pH value of human skin.

Research of the efficiency of organic matter removal from water using synthetic zeolite

Zoran Petrović — Fri, 08 Nov 2024 00:00:00 +0100

The paper investigated the effectiveness of using synthetic zeolite as an adsorbent for the removal of organic matter from water. Characterization of zeolite was performed using advanced testing methods: XRD, FTIR, BET and SEM/EDS. Raw water was analyzed for physicochemical characteristics before treatment (turbidity, color, pH, conductivity, content of organic matter, ammonia, nitrate and nitrite nitrogen, iron, manganese and chloride) and after treatment with an adsorbent (content of organic matter). Research on the efficiency of adsorption was carried out under the conditions of water temperature 25°C, individual doses of zeolite of 1, 2 and 4 g/L, mixing 200 rpm and adsorption time 60 minutes. The obtained results showed that by applying synthetic zeolite in a dose of 1 g/L, it is possible to achieve the removal of organic matter of 71.2%, while increasement of that dose up to four times has an insignificant effect on the adsorption efficiency.

Influence of maceration, solvent types, and extraction durations on the yield of milk thistle seeds (Silybum Marianum) extraction

Fri, 08 Nov 2024 00:00:00 +0100

ABSTRACT:

The study investigated the extraction yield of defatted Silybum marianum seed samples using maceration as the sole extraction technique. Different solvent types (methanol, ethanol, and water) and extraction durations were tested. Prior to extraction, the samples were ground and defatted with n-hexane. For each combination of solvent type, and extraction duration, the extracted mass (g of extract/g of defatted sample) was determined. The impact of each parameter on the yield was analyzed, revealing significant effects. Results showed that water-based maceration for 4 hours yielded the highest average mass of dry extract, followed by shorter durations at 2 hours. Ethanol occasionally outperformed methanol, particularly at the 2-hour mark, but methanol consistently produced lower yields across longer extraction durations. These findings emphasize the need for careful optimization of solvent type and extraction duration to maximize extraction yield. Subsequent analysis using Tukey's HSD test revealed significant differences in dry extract mass among solvents. Water yielded the highest at 2 and 4 hours, ethanol at 4 hours, and methanol at 4 hours as well.

Keywords: Silybum marianum; maceration; solvent types; plant extraction, yield analysis