Recent Submissions

  • Development of flour confectionery products with reduced sugar content

    Tumashov, A. A.; Gavrilov, A. S.; Chugunova, O. V.; Bulygina, O. Yu. (2021)
    Vestnik of MSTU
    The search for equivalent flavoring sugar substitutes of a non-sugar nature is an urgent direction in the development of the technology of flour confectionery products. In the course of research, a gingerbread recipe has been developed with a partial replacement of the prescription sugar with a 15 % solution of sucralose in glycerin, which most closely correspond to the organoleptic characteristics (taste, smell, texture) of traditional flour confectionery products. The results of the organoleptic evaluation of coded prototypes of gingerbread with the involvement of experts have shown that a decrease in sugar concentration by 25 % does not lead to a statistically significant change in organoleptic parameters in comparison with control samples. Substitution of more than 30 % sugar leads to an increase in the plasticity of the dough complicating the operation of the dosing mechanisms; at the same time, the taste of the products changes (these changes are noted during the tasting assessment); their consistency becomes denser. In the process of research, the stability of the quantitative and qualitative properties of gingerbread during storage has been proved. Experimental samples of gingerbread with 25 % reduced sugar content retain all the indicators established by GOST for their storage for 90 days without statistically significant changes. The decomposition of sucralose in the manufacture of the dough is 0.1 %, in the baking process – 2.6 %, during storage for 120 days – 6.7 % (of the loaded product). The developed recipe allows enterprises to expand the range of confectionery products with reduced sugar content.
  • Specialized sports nutrition products using protein hydrolysis compositions of collagen-containing fish raw materials

    Romanenko, N. Yu.; Mezenova, O. Ya.; Nekrasova, Yu. O. (2021)
    Vestnik of MSTU
    The development of specialized sports nutrition with components of collagen-containing fish raw materials is due to the shortage of domestic products of this group, the problem of fish waste processing, scientific data on bioactive peptides of marine origin. Low-molecular active peptides and protein-mineral compositions in the form of powder and liquid dietary supplements were obtained from the scales of sardine and sardinella by methods of deep hydrolysis. During the hydrolysis of raw materials, fermentolysis was carried out with the Alcalase 2.5L enzyme, thermohydrolysis – at temperatures of 130–140 °C. The chemical composition of the scales of two fish species, the products of its hydrolysis, and the amino acid composition of its proteins have been studied. The amount of low-molecular-weight peptides in hydrolysates of sardine scales was investigated by various methods of hydrolysis. Rational methods of hydrolysis of scales – enzymatic and enzymatic-thermal – have been substantiated. They make it possible to obtain protein supplements with protein content of 83.9–85.2 % with a proportion of active peptides with a molecular weight of less than 10 kDa 91.7–98.1 %. A technology for obtaining protein supplements from fish scales has been developed, and their amino acid composition has been studied. The presence of irreplaceable and ergogenic amino acids, accompanying nitrogenous compounds, valuable in sports nutrition, was shown in the peptide supplement. An increased content of calcium, phosphorus and magnesium in the protein-mineral dietary supplement being important for the musculoskeletal tissues of an athlete has been established. On the basis of protein supplements in dry and liquid forms with the addition of beekeeping products, the technology of chewing marmalade for sports nutrition has been developed. Bioproduct "Apikolltonus" belongs to the class of gainers with a protein content of 20.5 %, a carbohydrate of 41.6 % with an amino acid value of BCAA (isoleucine : leucine : valine) 2 : 1 : 1.5. A multicomponent bar for sports nutrition has been developed using protein hydrolysates of scales, flaxseed and apple cakes, and pine nuts. The bar is functional in terms of the content of calcium and phosphorus, dietary fiber, flavonoids, and vitamin E. Recommendations for the use of new sports nutrition products are substantiated.
  • Application of the linear method of discriminant analysis of reflectance spectra in the near infrared region for the species identification of fish of the Salmonidae family

    Novikov, V. Yu.; Rysakova, K. S.; Baryshnikov, A. V. (2021)
    Vestnik of MSTU
    It is well known that fish belonging to the Salmonidae family differ in their nutritional value. Anatomical and morphological features of different salmon species have a certain similarity; therefore, representatives of this family are most often falsified. Assortment falsification of products from fish of this family is usually carried out by replacing more valuable species with cheaper ones with a reduced nutritional value. Most often, counterfeiting of Atlantic salmon (salmon) by Far Eastern ones (chum salmon, pink salmon, chinook salmon, coho salmon) is found. Near infrared spectroscopy (NIR) is now increasingly used for identification and authentication of closely related organisms, in some cases being a rapid method replacing genetic analysis. We have obtained diffusion reflectance spectra of NIR radiation for three species of fish from the Northern Basin belonging to the salmon family. The best classification by fish species has been obtained by analyzing the NIR spectra of pre-dried fat-free muscle tissue samples. In case of wet samples, the observed differences are less significant, up to insignificant differences in individual values from neighboring clusters. The possibility of using the method of linear discriminant analysis of the NIR reflection spectra of muscle proteins for the species identification of fish has been shown.
  • Investigation of the chemical composition of pumpkin pulp as a basis for soft drinks

    Shkolnikova, M. N.; Abbazova, V. N. (2021)
    Vestnik of MSTU
    Pumpkin fruits (Cucurbita spp.) have a number of advantages and high technological potential, thanks to almost universal cultivation in a wide range of agro-climatic conditions, the ability to long-term storage, the content of dietary fibers, pectin and other polysaccharides, carotenoids, polyphenolic substances, vitamins, which cause a wide range of physiological orientation. In the process of researching the composition of local cultivars of pumpkin and the world experience of using Cucurbita spp. in the composition of food products, the need to use this ingredient in beverage recipes has been substantiated. The content of dry substances in the pumpkin samples is from 8.18 % ("Gribovskaya") to 11.6 % ("Orange bush"). The maximum sugar content is distinguished by the varieties "Winter Sweet" (6.87 %) and "Orange Bush" (7.40 %). The content of BAS-antioxidants is (without visible difference depending on the growing region): carotenoids from 1.3 mg/100 g in "Gribovskaya" to 2.0 mg/100 g – "Orange bush"; ascorbic acid – 8.7 mg/100 g in "Rossiyanka" to 14.2 mg/100 g – "Orange bush". Today all parts of the pumpkin fruit are used: the bark is a raw material for the production of feed flour and a substrate for the cultivation of lactobacilli, the seeds are traditionally used to produce pumpkin oil and flour, the pulp of the fruit is a raw material for juice-containing products, purees, carotenoid-containing and polysaccharide extracts, pectin, concentrates of first and second dishes, snack products, pasta, bakery, confectionery and meat products, etc.
  • Fatty acid composition of yogurt drink based on mare's milk

    Kanareykina, S. G.; Chernyshenko, Yu. N.; Kanareykin, V. I.; Rakhmatullina, I. F. (2021)
    Vestnik of MSTU
    In accordance with the local climatic conditions and folk traditions in the Republic of Bashkortostan, dairy horse breeding occupies a leading position. Mare's milk is a unique raw material for the production of a wide variety of highly nutritious, complete and easily digestible food products. Scientists recommend mare's milk as a medicinal and dietary product. The paper presents a yogurt recipe developed on the basis of a composition using mare's milk. The composition received patent No 2677219 (Composition…, 2019). It is known that mare's milk fat is rich in polyunsaturated fatty acids, which are of particular physiological importance for the human body. There is a need to ration and ensure a constant intake of polyunsaturated fatty acids of the ω-3 family with food. The purpose of this work is to study the fatty acid composition of yoghurt. To obtain a fermented milk product, milk from Bashkir mares was used as raw material. The production and research of prototypes of yoghurt were carried out on the basis of the Faculty of Food Technologies of the Bashkir State Agrarian University. The determination of the fatty acid composition of the yoghurt sample took place in the accredited testing laboratory centre "Federal Research Centre for Nutrition and Biotechnology" (Moscow). The use of mare's milk allows one to change the fatty acid composition of the finished fermented milk product. Analysis of the fatty acid composition of the sample has showed that it has a high content of oleic, γ-linolenic, α-linolenic and arachidonic acids.
  • Production technology and quality assessment of milk shakes for baby food with vitamin complex enrichment

    Boyarshinova, E. V. (2021)
    Vestnik of MSTU
    Diversification of dairy products for baby food is a topical trend in the development of the dairy industry. In the process of producing an ultra-heat-treated (UHT) milkshake, milk with a mass fraction of fat 3.5 %, skim milk with a mass fraction of fat 0.5 %, fruit filling "Cherry" and a vitamin premix are used. The technological process of production includes the acceptance of raw materials, assessment of their quality in accordance with regulatory documents; heat treatment of raw milk; preparation of a normalized mixture; adding ingredients. The prepared mixture is sent for deaeration to a flow-through apparatus, then to a homogenizer, where it is subjected to ultra-pasteurization at a temperature of 136 ± 2 °C with a holding time of 4 ± 1 s. The final stage of cocktail production is packaging and intermediate storage. The resulting product was tested in the laboratory for organoleptic and physicochemical indicators. During the experiments, it has been found that the taste, smell, colour, appearance and consistency meet the requirements of state standards. The content of protein, fat, carbohydrates, calcium and titratable acidity are within acceptable values; the content of vitamins A, D3, E, B6 is higher than the minimum values. The research results on safety indicators meet the requirements of technical regulations. Antibiotics, GMO-derived materials and preservatives are not found in the product. The energy value of the baby milk shake is 63.7 kcal (266.6 kJ/100 g of product).
  • Analysis of depolymerization of insulating compositions of electric motor windings based on ultrasonic radiation

    Kashin, A. I.; Nemirovsky, A. E. (2021)
    Vestnik of MSTU
    This work is a continuation of the fundamental study on implementing an innovative method of repairing electric motors using ultrasound. A study of the method of dismantling windings based on ultrasound has been carried out for the purpose of energy efficiency, environmental friendliness and less time spent on the repair cycle of electric motors in terms of removing the stator winding. The investigated dismantling method is optimal for a number of technical issues in comparison with the existing methods for dismantling electric motor windings. In the work, the main focus is on the material of the winding insulation. Lacquer and compound types of insulation of industrial electric motors, which are the main ones everywhere, have been analyzed. The analysis of the impregnating electrical insulating compositions of the stator windings of electric motors and the influence of ultrasound on them during dismantling of the windings of electric motors at different levels of influence of forcing factors: duration and power of ultrasonic action, concentration and temperature of the working solution. The applied mathematical software systems for calculation and modeling guarantee the reliability and rationality of the results of the experiments obtained during the work. A system of equations has been modeled and models of the effect of useful factors relative to each other have been constructed, the results obtained have been optimized and the optimal parameters of both varnish and compound insulation systems have been identified. The optimal parameters of the investigated types of insulation show encouraging results on many important points: duration, energy consumption, environmental friendliness.
  • Effects of bioactive compounds upon the deterioration of the chilled mechanically deboned poultry meat during storage

    Voitsekhovskaya, L. I.; Franko, Ye. V.; Verbytskyi, S. B.; Okhrimenko, Yu. I. (2021)
    Vestnik of MSTU
    Mechanically deboned poultry meat is a valuable protein containing raw material widely used for the production of meat products. However, it does not have a high resistance to oxidation; therefore, various antioxidants including those of natural origin are used in its composition. The article provides information on the advisability of using rosemary extract and dihydroquercetin to stabilize lipids and interrupt hydrolytic and chain oxidative processes in mechanically deboned poultry meat. The permissible storage time for mechanically deboned poultry meat using the rosemary extract and dihydroquercetin in a chilled state is 96 hours. Research has been carried out on the oxidative processes of the fatty complex of mechanically deboned poultry meat during the refrigerated storage period. Antioxidants prevent the accumulation of peroxides: in the samples with their use, the peroxide number reaches critical values on 6th–7th day of storage, without their use – on 3th day of storage. For all samples, a gradual increase in the acid number has been observed; however, for samples without antioxidants its values reach a critical level on the 4th day of storage, with the use of antioxidants – on the 7th day. The active formation of secondary oxidation products has begun from the second day of storage and reached the limit of permissible values in samples without antioxidants after 3 days of storage. In samples with antioxidants, the thiobarbituric number reaches a critical value on the 6th day. It has also been shown that the use of antioxidants contributes to the preservation of sensorial indicators (colour, odour) improving the quality of products. The efficiency of using the rosemary extract and dihydroquercetin as inhibitors of the oxidation of mechanically deboned poultry meat has been confirmed.
  • Resistance change of contact groups of low-voltage electrical apparatus: Determining the laws

    Gracheva, E. I.; Gorlov, A. N.; Alimova, A. N.; Mukhanova, P. P. (2021)
    Vestnik of MSTU
    The main Russian and foreign manufacturers of low-voltage electrical devices – circuit breakers, fuses, magnetic starters, knife switches and packet switches are presented. The data of experiments for determining the resistance values of contact groups of low-voltage switching equipment are considered. The design features of the devices that determine the value of the resistances of the power circuits of low-voltage equipment are investigated and a classification is proposed depending on the design elements of the devices. A methodological approach and an algorithm for experiments and detailed analysis of the contact groups of devices are given. Experimental schemes for the study of contact groups are proposed. The data of the conducted experiments on the study of contact groups and the resistance values as a function of the flowing currents are shown. During the experiments it is revealed that the value of the resistance of the contacts changes depending on the value, type and time of exposure to current within +/–5 %. The laws that characterize the ratio of the resistance values of the structural components of devices (contact systems, thermal relay, coil of the maximum relay) have been revealed and defined. Empirical expressions and graphical dependences of the resistances of contacts and contact systems are obtained as a function of the magnitude of the rated currents of low-voltage contact equipment. The minimum sample size of the number of devices during experimental research is determined, sufficient to calculate the mathematical expectation of the resistances of the contact connections of the devices with a given accuracy. As a result of experimental studies, it is revealed that the resistance value of contacts and contact joints can increase during operation by 2–2.5 times. The established dependences of the change in contact resistance can be used to predict the technical state of electrical installations of intrashop low-voltage networks, to clarify the amount of electricity losses in shop networks up to 1 kV, and can also be used as an additional regulation for maintenance and scheduled preventive maintenance.
  • Development of fermented product using dispersion from domestic breeding peas

    Veber, A. L.; Leonova, S. A.; Nikiforova, T. A.; Zhiarno, M.; Badamshina, E. V.; Lisin, P. А. (2021)
    Vestnik of MSTU
    Currently, there is a steady trend in the world aimed at finding new raw protein sources and their industrial processing into functional food products. The modern food market is represented among other things by non-alcoholic beverages from plant raw materials (vegetable "milk", fermented plant drinks), combined fermented milk products of complex raw materials, which are becoming popular among consumers and are in high demand among the population. The study shows the possibility of using pea grains of Bashkir Research Institute of Agriculture BashSC RAS (BRIA, Republic of Bashkortostan) varieties in the technology of obtaining fermented products. Consumer qualities, the chemical composition of pea varieties of the BRIA selection (Chishminsky 95, Chishminsky 229, Pamyati Khangildin, Yuldash) and their ability to germinate have been investigated. The possibility of their use for obtaining a plant dispersion intended for manufacturing fermented products from plant raw materials has been established.
  • Analysis of XLPE cable parameters subject to thermo aging

    Buev, S. A. (2021)
    Vestnik of MSTU
    Modern marine vessels use electrically driven rudders; cruise liners, gas carriers, tankers are equipped with Azipod systems manufactured by the Swedish-Swiss company ABB. Gondola-type propellers make it possible to break ice when the vessel is moving astern, therefore such vessels are used for work on the Northern Sea Route, in particular, when working on the Yamal LNG project. The 22MW Azipod propulsion system rotates 360° and enables difficult maneuvering without the assistance of tugs. When operating such propellers, powerful diesel generators are installed on the ship. For the transmission of electricity, ship cables are used, which are subject to increased requirements that meet the standard of the International Electrotechnical Commission. Modern marine vessels are equipped with XLPE or EPDM insulated cable lines; industrial production of these cables is carried out in the Russian Federation. In the course of the study, a method for auditing the state of insulation has been considered based on an assessment of the change in the tangent of the angle of dielectric losses in the process of thermal aging of the cable of the PvBPng(A)-HF brand. Measurements of the tangent of the dielectric losses' angle have been carried out with a Tangens-2000 insulation parameter meter.
  • Designing of specialized fish food products with a reduced content of nitrogen extractives

    Alekseev, G. V.; Eliseeva, S. A.; Smolentseva, A. A. (2021)
    Vestnik of MSTU
    The authors consider the possibility of using low-value pelagic fish species in the diet of people with restrictions on the consumption of nitrogenous extractive substances including nucleic acids which are sources of purine base metabolism. The objects of the study were chopped mackerel fillets from boiled fish and chopped boiled fillets from raw fish, quick-frozen minced horse mackerel of industrial processing in a boiled form. The studies were carried out in accordance with the experimental plan in which the duration of the heat treatment and the temperature of the cooking medium were the variable factors. The technology of combined fish masses with the addition of functional plant components has been proposed. It has been established that the dynamics of dry matter losses and heat losses of fish fillets is determined by the duration of cooking. In terms of organoleptic characteristics boiled minced meat from raw mackerel fillets is significantly inferior to the organoleptic characteristics of minced meat from pre-boiled fillets. When comparing the data for frozen and freshly prepared mince from horse mackerel, it has been found that the loss of nucleic acids in industrially prepared minced meat is 4.6–13.1 % higher (T = 82 ± 2 and 98 ± 2 °C), the loss of nucleic acids by absolutely dry matter is higher by 11.3–5.8 %, mass – by 8.4–14.6 %. The content of the total amount of nucleic acids in industrial minced meat is 11.1 % lower than in freshly prepared minced meat. Obviously, in the process of preparing products for specialized purposes, including for preventive nutrition, it is preferable to use minced meat from boiled fish fillets.
  • Chemical composition of sea buckthorn (Hippophae rhamnoides L.) berry grown in the Chelyabinsk region

    Naumova, N. L. (2021)
    Vestnik of MSTU
    The most important phytonutrients of sea buckthorn (Hippophae rhamnoides L.) berry are carotenoids, flavonoids, anthocyanins, sugars, organic and amino acids, water and fat-soluble vitamins, tannins and pectin substances, phospholipids, macro- and microelements. In the Chelyabinsk region it is almost impossible to find well-groomed industrial plantings of sea buckthorn, since its main areas (600 hectares) are concentrated in amateur and home gardens. To form a healthy diet, it is important not only to ensure the safety of horticultural products, but also to raise the priority of signs that determine consumer demand, namely the quality and chemical composition of fruits, their saturation with the necessary micronutrients. While studying food and biologically active substances of sea buckthorn berries of the "Velikan" variety growing in different garden agrocenoses of the Chelyabinsk region it has been determined that sea buckthorn berries cultivated in the garden "Lokomotiv-1" (Chelyabinsk) contain more flavonoids (by 21.4 %), proteins (by 17.4 %), mineral elements – Al (in 5.3 times), V (3.4 times), Cu (3 times), Ti (2.4 times), Ca and Fe (1.9 times), Mn (1.5 times), in berries obtained in the garden "Dizelist-1" (Chelyabinsk region, Troitsk) contains more sugars (by 15.1 %), as well as Mo and Sr (2–2.3 times), Se (1.4 times), Cr (by 76.2 %), etc. In terms of Se content, the studied fruits exceed the clarke values by 4–6 times; in terms of Pb content, they turned out to be as close as possible to the upper limit of MPC according to the requirements of the Technical Regulations of the Customs Union. The study of the mineral composition of sea buckthorn is especially important in the context of the ecological disadvantage of the Chelyabinsk region due to the pollution of the environment with heavy metals.
  • New varieties of wheat, triticale and spelt grains: Comparative characteristics of milling properties

    Kandrokov, R. H.; Begeulov, M. S.; Tkach, A. N.; Igonin, V. N.; Porechnaya, E. S. (2021)
    Vestnik of MSTU
    Triticale and spelt grains are non-traditional types of plant raw materials that are promising for expanding the range of everyday products, healthy foods, as well as for the manufacture of food additives. A promising and relevant direction of scientific and practical research is the use of methods of biomechanical impact on the products of processing grain triticale and spelt grain in the form of flour, crumbs and bran to obtain food for general, functional and therapeutic purposes. The aim of the research is a comparative characteristic of the milling properties of new varieties of grain of wheat, triticale and spelt and the possibility of theit using for grinding into flour at existing grain processing enterprises. A comparative characteristic of the cereal-forming ability of new varieties of wheat, triticale and spelt has been carried out and it is revealed that the best cereal-forming ability belongs to the spelt grain of the "Gremme 2 U" variety, equal to 79.8 %, which is 4 % more than that of the wheat grain of the "Timiryazevskaya Jubilee" and 4.8 % of triticale grain of the "Timiryazevskaya 155" variety. It has been found that the highest flour yield under the same grinding regimes is obtained when grinding the grain of a new type of spelt "Gremme 2 U" amounted to 79.3 %. The largest amount of triticale flour of the highest grade T-60 is obtained from triticale grain of the "Timiryazevskaya 155" variety. The grain of wheat "Timiryazevskaya Jubilee" occupies an intermediate position both in terms of the total yield of flour and its quality compared to spelt and triticale. All three given new varieties of various crops have good flour-grinding properties and can be recommended for processing into high-quality bakery flour at flour mills when making grinding mixtures.
  • Substantiation of a rational method for drying granules in a fluidized bed and the hydrodynamic regime of their interaction with a fluidizing agent

    Nugmanova, A. A.; Aleksanyan, I. Yu.; Nugmanov, A. H.-H.; Maksimenko, Yu. A.; Khaybulov, R. A. (2021)
    Vestnik of MSTU
    Gluten is produced from wheat grains and is used in the food industry as an improver in flour baking properties. On the basis of a comparative analysis of the methods of dehydration of frozen granules of wheat gluten with a surface dry crust, a rational method of drying them in a fluidized bed has been selected. In the process of calculating units with a fluidized bed, its hydrodynamic parameters have been determined: loss of the pressure of the fluidizing agent; the speed at the transition of the bed from the state of rest to the pseudo-boiling mode; layer porosity; the rate of entrainment of particles in unrestricted conditions roughly corresponding to the rate of soaring, at which a single particle is in equilibrium in the gas flow. During the dewatering operation, the rate of entrainment of the granules varies; therefore, it is advisable to use the passing fluidization mode depending on the decrease in their moisture content. In the variant of the active hydrodynamic regime in the drying unit, the dehydration procedure is intensified without a noticeable decrease in the economic efficiency of its functioning and high quality indicators of the finished product with the given final moisture are provided, which is due to the specific conditions of contact of the granules with the coolant. For granules with a moisture content of 0.19 kg/kg, the values of hydrodynamic characteristics have been determined: the area of critical pseudo-boiling rates is 4.1–5.5 m/s; the carryover rate of the fines is 12.5–14.5 m/s. As a result of the study, the choice has been substantiated in favor of drying the studied granules in a fluidized bed due to the prevalence of its advantages over the dehydration of the object in drum dryers.
  • The study of biotechnological potential of Lactobacillus sakei LSK-103

    Nikiforova, A. P.; Khamagaeva, I. S. (2021)
    Vestnik of MSTU
    Lactic acid bacteria play an important role in the production of food. Bacterial cultures widely used in the food industry often have a set of characteristics that ensure the stability of the production. The biotechnological properties of Lactobacillus sakei LSK-103 have been studied in the present work. Lactobacillus sakei LSK-103 has shown high biochemical activity on MRS medium. It has been found that after 16 h of cultivation at the end of the exponential growth phase, the number of viable bacterial cells reaches 109 CFU/cm3. The study of the effect of different concentrations of sodium chloride on biomass accumulation has shown that Lactobacillus sakei LSK-103 is highly resistant to salt. Increase in NaCl concentration from 2 to 10 % leads to decrease in cell survival from 96.8 to 91.2 %, and in number of bacteria to 108 CFU/cm3. Morphological studies indicate that an increase in the concentration of sodium chloride in the medium is accompanied by cell cohesion, the formation of cell conglomerates. Cohesion intensifies intercellular contacts and increases the resistance of Lactobacillus sakei LSK-103 to osmotic stress. The high survival rate of Lactobacillus sakei LSK-103 has been shown in the presence of bile, phenol (0.4 %), high (pH 8.3) and low (pH 3.5) values of active acidity of the medium indicating its probiotic properties. The results of research have shown that the Lactobacillus sakei LSK-103 has high biotechnological potential and can be used as part of bacterial preparations for the production of fermented fish products.
  • Chemical and enzymatic destruction of chondroitin sulfate from Arctic skate

    Kuchina, Yu. A.; Konovalova, I. N.; Novikov, V. Yu.; Dolgopyatova, N. V.; Kuznetsov, V. Ya. (2021)
    Vestnik of MSTU
    Due to its biocompatibility with human and animal tissues, low toxicity, and biodegradability, chondroitin sulfate (CS) is of great interest for medicine. Since CS is used as a pharmaceutical preparation, its molecular weight and solubility determine the possibilities of its use. This work presents the results of studying the chemical and enzymatic destruction of CS macromolecules and its effect on the molecular weight, solubility and crystallinity degree of the polysaccharide. CS was obtained from the cartilaginous tissue of the Arctic skate (Amblyraja hyperborea). At the stage of cartilage tissue fermentolysis, the enzymes pancreatin, hepatopancreatin and protosubtil were used. The obtained CS samples were identified by IR spectroscopy. Enzymatic destruction of glycosidic bonds in cholesterol macromolecules was carried out with a 1 % solution of the enzyme hepatopancreatin, chemical destruction with hydrogen peroxide and hydrochloric acid. The CS content in the samples was determined by the Dische method. The chemical composition of CS samples was evaluated by standard methods. The average molecular weight (MW) was determined using high performance liquid chromatography and the nephelometric method. The crystallinity degree (CD) was determined by graphical processing of diffraction patterns obtained by X-ray phase analysis of CS samples. It was found that under the action of hepatopancreatin and hydrogen peroxide, deep destruction of chondroitin sulfate occurs, to the formation of low molecular weight and oligomeric fragments. Under conditions of acid destruction in 0.5 N HCl for 20 min the MW of chondroitin sulfate is reduced by 10 % compared to the initial one. Acid destruction causes a significant decrease in the CD of the CS samples. For CS samples not degraded in acid, the solubility in distilled water increases with decreasing MW and CD. The solubility of CS after acid destruction in the range of pH = 5–9 units is 99.0 ± 0.5 %. This high solubility is most likely explained by the significant content of the amorphous phase in the samples.
  • Evaluation of the effect of enzymatic hydrolyzate of the bursa of broiler chickens on cytotoxic activity and nonspecific immunity

    Kolberg, N. A; Leontieva, S. A.; Tikhonov, S. L.; Tikhonova, N. V.; Shikhalev, S. V.; Kirpikova, K. E. (2021)
    Vestnik of MSTU
    The use of biologically active substances of tissue origin for the creation of biologically active additives and immunomodulatory drugs is an important area of scientific research in the field of nutrition and pharmacology. The aim of the work is to evaluate the effect of enzymatic hydrolysate from the fabricium bag of broiler chickens on the cytotoxicity and nonspecific immunity of mice against the background of experimental salmonella infection using biotechnological methods. For the experiment, three equal experimental groups of white mongrel mice were formed. All laboratory animals were fed daily for seven days with enzymatic hydrolysate at a dose of 750 mg/kg (therapeutic dose), 150 mg/kg (0.2 therapeutic dose) and 3,750 mg/kg (five therapeutic doses). At the same time, the control group of animals received intragastric water in the same volume. 24 hours after the last intake of the enzymatic hydrolysate, the animals were intraperitoneally infected with a culture of Salmonella enteritidis 92. The study reveals the absence of cytotoxic properties and impaired cell viability in cultures L929, J774.1A, HeLa S3, K562, and HST116 against the background of exposure to various concentrations of enzymatic hydrolysate from 0.02 to 10 mg/ml. It should be noted that there is a pronounced cytotoxic effect on MCF-7 tumor cells of the concentration of enzymatic hydrolysate in culture of 5 and 10 mg/ml, which suggests the possibility of using enzymatic hydrolysate for the prevention of tumor diseases. As a result of the experiment, it has been proved that the administration of enzymatic hydrolysate to mice increased the LD50 index and the survival rate of mice infected with the culture of the causative agent of salmonellosis by 1.5 times. Based on the conducted studies, it has been shown that the enzymatic hydrolysate of the lymphoid tissue of broiler chickens does not violate the viability of mammalian cells and does not exhibit cytotoxic properties on the metabolism of healthy mammalian cells, which indicates its safety. In an experiment on mice, the effect of enzymatic hydrolysate of the fabricium bag of broiler chickens on the activation of nonspecific immunity against salmonella infection has been revealed.
  • Development of a functional bread technology based on a grain baking mixture

    Alekhina, N. N. (2021)
    Vestnik of MSTU
    One of the priority areas for developing the food industry is to increase the production of functional food products. When developing the latter, fruit and berry processing products, grain baking mixes are used. At the same time, there are no baking mixes with the use of bioactivated wheat, characterized by an increased content of macro- and micronutrients, antioxidants, and a reduced amount of phytin. However, the preparation of grain bread based on a baking mixture of bioactivated wheat crushed by the disintegration wave method with a moisture content of 10.0 ± 0.5 % led to the production of products with a sticky, strongly jamming crumb. The aim of the research was to develop a baking mixture of bioactivated wheat and functional grain bread of improved quality based on it. At the first stage of the research, the composition of the baking mixture based on bioactivated wheat grain was selected to obtain the best quality product, at the second stage, the chemical composition of bread was evaluated based on the developed baking mixture. The change in the properties of the dough during fermentation, the quality indicators of bread after 20 hours of storage and its chemical composition were evaluated in accordance with the methods specified in the current standards. The best properties of the dough and the quality of the bread have been observed in a sample obtained on the basis of a baking mixture, in 100 g of which 75 % of the grain products are dry bioactivated wheat crushed by the disintergation-wave method, and 25 % – baking wheat flour of the first grade. As a result of the assessment of the chemical composition of the developed product, it has been found that it belongs to functional food products. The preparation of grain bread using this technology will also allow us to solve one of the tasks of the state policy in the field of healthy nutrition aimed at increasing the production of functional products.
  • Numerical simulation of the thermal regime of an underground spent fuel storage facility (built-in structure variant)

    Amosov, P. V. (2021)
    Vestnik of MSTU
    The results of a numerical simulation of the thermal regime of an underground facility for long-term storage of spent nuclear fuel in a built-in reinforced concrete structure are presented. Two computer models were constructed in a three-dimensional formulation in the COMSOL programme. The first model is based on the incompressible fluid approximation, while the second model is based on the "incompressible ideal gas" approximation. The mathematical basis of models: the continuity equation, Navier – Stokes equations averaged by Reynolds, the standard (k – ?) turbulence model, and the general heat transfer equation. Consideration of mixed convection conditions is implemented in the "incompressible ideal gas" approximation, where the air density is a function of temperature only. The most thermally stressful arrangement of spent fuel placement is investigated: U-Zr – defective – U-Be. The air rate is varied in the range from 21 to 0.656 m3/s. Numerical experiments were performed for up to 5 years of fuel storage. The principal difference between the non-stationary structure of the velocity fields predicted in the "incompressible ideal gas" model and the "frozen" picture of the aerodynamic parameters in the incompressible fluid model is emphasized. It is shown that the requirements for exceeding the temperature limit values are met when the object operates under conservative ventilation conditions (rate 0.656 m3/s) with a minimum of costs for organizing ventilation. The dynamics of heat flows directed into the rock mass through the base and from the surface of the built-in structure of the U-Zr fuel compartment to the air environment are analyzed. The predominance of the heat flow from the surface of the structure and the different times when the curves of the heat flow dynamics reach their maximum values are noted. The heat flow to the array reaches its maximum significantly faster than to the air.

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