Introduction. Chemical factor presupposes substances that enter the finished product and reduce its quality. Water used in production process can be a source of such substances. The domestic drinking water supply system may contain various contaminants that possess toxic and carcinogenic properties and can affect the quality characteristics of food products. Study objects and methods. The research featured popular water pollutants found in the drinking water supply system, components of fruit and whey beverages, and the process of adsorption extraction of the contaminants by various sorbents. Results and discussion. The paper focuses on the effect of water contamination as a dangerous chemical factor on the quality of restored whey products. The study revealed the effect of organic water pollutants on the formulation components of reduced fruit and whey beverages, including interaction with proteins, lactose, and vitamins of the reduced whey. The research also featured such components of fruit and whey vitamin beverages as anthocyanins, catechins, leucoanthocyanins, and karatine, as well as additives introduced to regulate the sensory properties and improve shelf life. The paper introduces a new method for reducing water contamination based on adsorption processes for extracting organic compounds from aqueous solutions. It describes the specifics, patterns, and mechanisms of adsorption. Activated carbons of SKD-515, AG-OV-1, and AG-3 brands proved to have the best adsorption capacity for both chloroform and trichloroethylene, which makes it possible to recommend them for further research and practical use. A study of the kinetic and dynamic characteristics of the process resulted in the optimal parameters of adsorption columns and operation modes of the adsorption filter. A production flowchart describes the introduction of the adsorption posttreatment stage in the technological process of producing fruit and whey beverages. Conclusion. The proposed method of water decontamination partially reduced the chemical factor and improved the quality of the finished products.

Methods are presented for investigating the site and form of growth of bacteria in model oil-in-water emulsions and in dairy cream. Following growth of the bacteria, the continuous aqueous phase is gelled using agarose and the oil phase removed using a mixture of chloroform and methanol. Using this method, the authors have found that Listeria monocytogenes, Salmonella typhimurium and Yersinia enterocolitica grow in the form of colonies in concentrated oil-in-water emulsions. Colonies of L. monocytogenes and Y. enterocolitica also form in artificially-inoculated fresh and tinned dairy cream. If information about the precise site of growth is not required, the authors have discovered that intact colonies can be liberated from the model emulsions by dissolving away the oil phase with chloroform: methanol.

A method is proposed for the identification of surfactants by ultra-performance liquid chromatography (UPLC) with high-resolution mass spectrometry detection after screening water and food samples for the total concentration of cationic and anionic surfactants by microextraction–fluorimetry. The method is based on the use of dispersive liquid–liquid microextraction with chloroform of surfactant ion pairs with organic reagents (eosin and acridine yellow), measuring the fluorescence of the obtained adducts using a smartphone, obtaining RGB colorimetric characteristics, and determining the total surfactant concentration. The main analytical characteristics of the identification of cationic surfactants (alkylpyrdinium, alkyltrimethylammonium, alkyldimethylbenzylammonium (benzalkonium), alkylmethylethylbenzylammonium, didecyldimethylammonium, benzyldimethyl[3-(myristoylamino)propyl]ammonium, N,N-bis(3-aminopropyl)dodecylamine chlorides) and anionic surfactants (alkyl benzene sulfonates (sulfonol), alkyl sulfates, laureth sulfates, alkyl sulfonates, and sodium alkyl carboxylates) by chromatography–mass spectrometry under the selected conditions of chromatographic separation and mass spectrometric detection are found. The features of the chromatographic behavior of the surfactant polymerhomologs under the conditions of UPLC and gradient elution are considered.

A novel method based on ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME) has been developed for the preconcentration of cobalt prior to its determination by graphite furnace atomic absorption spectrometry. In the UASEME technique, chloroform was used as the extraction solvent, sodium dodecyl sulfate was adopted as emulsifier, and ultrasound was applied to assist emulsification. There is no need of using organic dispersive solvent which is typically required in conventional dispersive liquid–liquid microextraction method. Several parameters that affect the extraction efficiency, such as the kind and volume of the extraction solvent, the type and concentration of the surfactant, pH of sample solution, concentration of the chelating agent, and extraction time and temperature were investigated and optimized. Under the optimal conditions, the linearity of calibration curve was in the range of 0.1–5 ng mL⁻¹with a correlation coefficient (R²) of 0.9992. An enrichment factor of 58 was achieved with a sample volume of 5.0 mL. The detection limit of this method for Co was 15.6 ng L⁻¹, and the relative standard deviation (RSD) was 4.3 % at 1.0 ng mL⁻¹concentration level of Co. The accuracy of the developed method was evaluated by analysis of the certified reference materials GBW07605 tea leaf and GBW10015 spinach. The method was successfully applied to determine trace cobalt in food and water samples with satisfactory results.

A simple and efficient determination of curcumin in water and food samples based on the combination of dispersive liquid–liquid microextraction (DLLME) and spectrophotometric estimation has been described. The effects of DLLME effective parameters [extraction solvent (CHCl₃), disperser solvent (ethanol), pH, centrifugation time, and KCl concentration] were optimized via central composite design (CCD) and response surface methodology (RSM) and desirability function (DF) using STATISTICA. At optimum condition specified as 150 μL of chloroform, 900 μL of ethanol, pH = 4.0, and 4 min of centrifugation time in the absence of any salt, a linear calibration graph in the range of 10–2000 ng mL⁻¹ of curcumin with R ² = 0.99942 (n = 6) confirms good applicability of the method for quantification of analytes over a wide range of analytes. The reasonable limit of detection (LOD) and quantification (LOQ) (0. 23 and 0.78 ng mL⁻¹, respectively) makes it suitable for trace analysis. Good relative standard deviation [1.16–2.3 % (n = 12)] and high enrichment factor (EF) 2182.04 are a good remark of the present method. Curcumin with relative standard deviation (RSD) less than 3 % (n = 4) and recoveries in the range 91.76–100 % can be successfully quantified in different real samples.