Characteristics Of Raw Materials Research Articles

The key to ancient Roman mortars hydraulicity: ceramic fragments or volcanic materials? A lesson from the Phlegrean archaeological area (southern Italy)

This research deals with mineralogical, petrographic, chemical, and microstructural characterization of raw materials from the Roman Dragonara cave (Phlegraean Fields, Campania region, Italy) through Polarized Light Microscopy (PLM), X-ray Powder Diffraction (XRPD), Field Emission Scanning Electron Microscopy coupled with an Energy Dispersive Spectrometer (FESEM/EDS), Simultaneous Thermal Analysis (STA) and Mercury Intrusion Porosimetry (MIP). The aim of this study was to asses mortars hydraulic properties along with provenance of raw materials and mortars recipe. A focus on the reactions between the surface of the ceramic aggregates and volcanic materials with binding matrix proved to be crucial to define their role in the mix design of mortars. Representative results showed that hydraulicity of the analyzed mortars is mainly due to volcanic materials rather than ceramic fragments. In fact, reaction active elements such as Reaction Rims (RR), Interfacial Transition Zones (ITZ) and particularly Ca-rich rims were usually found at the matrix-volcanic fragments interface. Moreover, porosity tests evidence that bedding mortars, which contain mainly volcanic material and only sporadically ceramic fragments have a higher closed porosity of binder matrix due to the good pozzolanic reactivity.

New deposit of chocolate flint in Załęże gully (Kraków-Częstochowa Upland, Poland) – Raw material characterization and its availability for prehistoric communities

One of the valued chert raw materials used by prehistoric communities in Central and Eastern Europe was chocolate flint. Despite finding artefacts made of it over a wide area, for many years, it was thought to occur only in one location - in the Holy Cross Mountains in Poland. However, the discoveries of recent years have shown that deposits of this raw material also occur in another region of Poland, in the northern part of the Kraków-Częstochowa Upland (KCU). The result of intensive field surveys conducted in this area is the finding of a new outcrop of chocolate flint in Załęże gully (Lesser Poland voivodeship) described in this paper. Based on the results obtained from the radiocarbon and optically stimulated luminescence dating of sediments co-occurring with the flint deposit, a history of the paleogeographic development of this gully has been proposed. Access to the deposit in its present form is limited to modern times, but it was likely accessible elsewhere in this area. Macroscopic and microscopic (using optical and cathodoluminescence microscopy) examinations showed a high similarity with the material of other KCU provenance from the prehistoric mine in Poręba Dzierżna, site 24. In the vicinity of Załęże gully there are many archaeological sites where chocolate flint artefacts were found. Preliminary research suggests that they could have been made from the raw material from the newly discovered outcrop. The new location of chocolate flint occurrence in the KCU region described here is another premise to re-think the existing interpretations related to the extraction, use and distribution of this important chert raw material in prehistoric times in Central and Eastern Europe.

Eco-Friendly Pavements Manufactured from Mixed Recycled Aggregates Obtained from Construction and Demolition Waste: An Industrial-Scale Validation.

This study aimed to validate that laboratory-scale results could be commercially replicated when manufacturing marketable precast concrete. Construction and demolition waste (CDW) was separated into two (fine and coarse) recycled aggregates (RAs). Precast paver and kerb units were fabricated by partial or total substitution of natural aggregates (NAs) by RAs. The study involved the comprehensive characterisation of raw materials, including particle size distribution, mineral composition, and elemental composition. Paver blocks and kerbs manufactured with up to 50% RAs showed mechanical resistance (T = 3.7 ± 0.2 and B = 5.3 ± 0.6 MPa, respectively), water absorption between 5.3-5.7%, and abrasion resistance (approximately 20.2 mm), which met the standard requirements (UNE-EN 1340:2004 and UNE-EN 1338:2004). Furthermore, industrial-scale precast pavement units demonstrated strength and durability suitable for heavy traffic areas. A reduction of 13% in cement content could maintain the requirements with a partial RA substitution of 25%, offering economic and environmental benefits. Therefore, it is feasible at an industrial level to replace NAs with RAs, promoting durability and technological properties with a positive environmental impact and considerably reducing CO2 emissions by up to 65%. Overall, pavers with RAs manufactured at the laboratory scale met mechanical standards, and the kerb stones showed improvements in abrasion resistance. On an industrial scale, kerb stones and precast blocks with specific substitutions can meet strength, water absorption, and abrasion requirements, allowing a reduction in cement content.

Medical and biological justification for the use of venison in special food products

Data on the biological and nutritional value of venison have been studied. Justification for the use of venison and the development of meat cream using it has been carried out in KubSAU named after I.T. Trubilin. As a result of the research, the venison market in Russia has been analyzed, and to substantiate the biotechnological requirements for the composition and quality of meat cream intended for feeding residents of the Far North have been substantiated; quality characteristics of the main raw material – venison and additional raw materials have been selected and assessed. Using the method of calculating quantitative and qualitative characteristics of the selected ingredients, the combination of formulation components that enrich the developed product with natural biological elements has been determined. The recipe composition of meat cream based on venison has been modeled. Pilot batch of meat cream has been developed with subsequent assessment of nutritional and biological value. A study conducted on the Daily supply of the main nutrients of the developed special-purpose meat cream, provided for the social group of people (residents of the Far North) has been studied and it has been revealed that the body’s energy costs are 15% higher, and the need for protein and fat consumption also increases to 140 g. Moreover, it has been revealed that the product is rich in vitamin B, which fully meet the daily requirement, vitamin A, which provides up to 29.3%, and vitamin C, up to 38% of the daily requirement. The developed meat cream meets the protein content requirements of 15.3%; fat of 19%; salt of 2%.

Synergistic effect of characteristics of raw materials on controlling the mechanical properties of fly ash-based geopolymers

This study investigates the macro- and micro-characteristics of the geopolymers to verify the feasibility of prediction of compressive strength via quantitatively adjusting the amorphous phase content (APC) and particle size distribution (PSD) of raw material. The optimization of PSD through the sieving method does not reach the intended compressive strength compared to the reference, while controlling APC by partly replacing fly ash with slag achieves the expected target. The critical reasons are well explained by the micro properties of geopolymers. The sieving process leads to the reduction in the porosity but has little effect on the Si/Al molar ratio and APC of geopolymers, which is related to the heterogeneous distribution of active constituents of fly ash. By contrast, the addition of slag significantly enhances the microstructure of geopolymers, especially by the interaction between C-A-S-H and N-A-S-H gel. As a result, the compressive strength is primarily determined by the micro index MCa, proved by the mutual positive correlation. Besides, given the low reaction rate of fly ash in the geopolymerization and relevant experimental results, the modified formula that only uses the APC and specific gravity (G20°C) of powder raw materials to establish the relationship with compressive strength owns a better linear dependence and probably more appropriate for the prediction of mechanical properties of fly ash-based geopolymers.

Influence of dextrins and β-glucans on palate fullness and mouthfeel of beer

Palate fullness (PF) and mouthfeel are important sensory attributes influencing beer quality. The molar mass of starch (dextrins) and non-starch (β-glucans) polysaccharides may influence PF (pleasant) or mouthfeel (sliminess, unpleasant), respectively. Therefore, this research aims to generate beer with wide physico-chemical responses based on various raw material characteristics to study its relation to PF and mouthfeel. To accomplish this, ten barley varieties (two harvest locations and years) were classified into three groups based on their modification characteristics. To intensify response variation, barley was malted at two modification levels (parameter steeping degree), generating 55 independent malts used to brew the same number of standardized bottom fermented beers. A trained sensory panel evaluated PF (intensity and quality) and mouthfeel (e.g., slimy) descriptors. Additionally, beers were fractionated by asymmetrical flow field-flow fractionation (AF4) in three different fractions and their molar masses were determined. The average molar mass of big size (> 10 nm) dextrins and β-glucans AF4 fraction increased analogously to barley modification characteristics. For sensory data evaluation, only beer samples brewed with malts inside the recommended brewing specifications were considered (β-glucan content in malt < 350 mg/L, ISO 65 °C). PF quality was lower on samples with β-glucan content < 100 mg/L. This group also contained fewer dextrins (attenuation > 87.4 ± 1.5%), suggesting that the balance of β-glucans and dextrins is important for PF quality. This work indicates that molar mass of starch and non-starch polysaccharides, affected by barley variety and its modification level, influences sensory perception, and hence, beer quality.Graphical

Experimental study of microwave processing of pine nut shells into a high-calorie gas: main results and physicochemical features

Involving biomass in the energy sector is a way to replace fossil fuels with renewable and CO2-neutral raw materials, reducing the negative impact on the environment. The energy application of agro-industrial waste is of particular interest, allowing one not only to obtain biofuel, but also to utilize by-products. The present work considers pine nut shells from a candy factory in relation to microwave processing into solid and gaseous fuels. The aim is to study the features of pine nut shells microwave pyrolysis, including the initiation mechanism and process behaviour, as well as the composition and characteristics of the resulting products. The study included experimentation in combination with application of high-speed video recording of the process and gas analysis, study of dielectric characteristics of raw materials, proximate and ultimate analysis of the obtained solid and gaseous products. At microwave pyrolysis, the conversion degree into liquid and gaseous products (76.9%) is much higher than, for example, at slow fixed bed pyrolysis (65.5%). The radiation absorption by the sample is nonlinear throughout the process and increases during the organic part degradation with the appearance of liquid and gaseous products. The gas obtained at microwave processing has a low ballast (share of CO2=3.5%) and a high hydrogen content (share of H2=19.3%) that results in a high heat of combustion (21.8 MJ·m-3), which is probably connected with interaction of pyrogenetic water and fuel carbon during plasma-chemical reactions.

Application of Sunflower Husk Pellet as a Reducer in Metallurgical Processes.

In relation to the climate policy being introduced, the search for a replacement for solid fossil fuels with renewable raw materials is ongoing. In this study, a potential biomass (sunflower husk pellet) application in the process of copper slag reduction was assessed. For the purpose of raw material characterisation, thermogravimetric tests were carried out and characteristic temperature points were determined with the use of a high-temperature microscope. The slag reduction tests led to the recovery of 97% of copper and a decrease in this metal content in the slag to less than 0.5% Cu, which enables safe storage or use in other industrial branches.

Technological adequacy of sugar beet products used in the food industry

Beet sugar production in Russia annually gives about 6 million tons of white sugar and 1.5 million tons of beet molasses, which must have technological adequacy, when used as raw materials. The purpose of the work was to substantiate the concept of technological adequacy of beet sugar production, its indicator markers and their threshold values, to assess the actual technological adequacy of white sugar and molasses, to verify the hypothesis about the relationship between individual indicators of white sugar and empirical knowledge about an increase in the content of micronutrients with a decrease in the category. The objects of the study were terminology related to the characteristics of food products and raw materials in terms of consumer expectations and indicators of their assessment. Technological adequacy was evaluated for 230 samples of white sugar and 134 samples of beet molasses. Indicator markers were determined according to standardized and known methods. Technological adequacy of white sugar and beet molasses is the compliance of their specific functional properties with the requirements of the production of a particular food product, in which they are raw ingredients. A measure of compliance is indicator markers in the form of physicochemical parameters of the composition. Indicators of white sugar for three food technologies and indicators of beet molasses for two technologies and storage were substantiated; their technological adequacy was assessed. Empirical knowledge about an increase in the content of micronutrients with a decrease in the category and the hypothesis about the relationship between individual indicators of white sugar were confirmed. It is shown that all white sugar of extra and TC1 categories has technological adequacy for the use in food production, while only 62% of TC2 sugar and some batches of beet molasses have the necessary technological suitability. The results obtained will be a tool for regulating the production of competitive products and developing a control scheme for the technological flow of sugar production.

A Tailored Approach in the Bentonite-like Raw Material Characterization Using Thermal and Water Sorption Techniques

Clayey raw materials present a wide variety of uses depending on their specific composition. Bentonite-like clays are considered suitable candidates to be used in some industrial applications, such as pharmaceutics, catalysis, antibacterial agents or food additives because of their highly desired adsorption properties, concretely regarding water vapor behavior. In the present study, a specific methodology for the characterization of some clayey raw materials used in the ceramic industry and its correlation with water vapor sorption properties is presented. Six different clayey raw materials have been wholly characterized until their specific chemical formula are obtained, and their water vapor adsorption behavior was correlated to their specific composition. The whole protocol has been validated with certified standard reference materials. The obtained results show a relationship between montmorillonite content in clay with water vapor adsorption behavior and certain thermal events of clayey particles, which can help the industry to understand product behavior and characterization during ceramic manufacturing process.

Hyaluronic Acid-Based Injective Medical Devices: In Vitro Characterization of Novel Formulations Containing Biofermentative Unsulfated Chondroitin or Extractive Sulfated One with Cyclodextrins.

Currently, chondroitin sulfate (CS) and hyaluronic acid (HA) pharma-grade forms are used for osteoarthritis (OA) management, CS as an oral formulations component, and HA as intra-articular injective medical devices. Recently, unsulfated chondroitin, obtained through biofermentative (BC) manufacturing, has been proposed for thermally stabilized injective preparation with HA. This study aimed to highlight the specific properties of two commercial injective medical devices, one based on HA/BC complexes and the other containing HA, extractive CS, and cyclodextrins, in order to provide valuable information for joint disease treatments. Their biophysical and biomechanical features were assayed; in addition, biological tests were performed on human pathological chondrocytes. Rheological measurements displayed similar behavior, with a slightly higher G' for HA/BC, which also proved superior stability to the hyaluronidase attack. Both samples reduced the expression of specific OA-related biomarkers such as NF-kB, interleukin 6 (IL-6), and metalloprotease-13 (MMP-13). Moreover, HA/BC better ensured chondrocyte phenotype maintenance by up-regulating collagen type 2A1 (COLII) and aggrecan (AGN). Notwithstanding, the similarity of biomolecule components, the manufacturing process, raw materials characteristics, and specific concentration resulted in affecting the biomechanical and, more interestingly, the biochemical properties, suggesting potential better performances of HA/BC in joint disease treatment.

Development of a Biodegradable Material with Oregano Stick as a Prototype of Substitute for Wooden Agglomerate Material

Oregano is a herb that is found in the wild in different parts of the world. The stick represents about 60% of the plant and is biodegradable, using lactic acid as a binding agent for the oregano stick. Waste oregano stick can be used to make biodegradable material which provides sustainable development in support and promotion of the circular economy by reducing pollution generated by chemical economy by reducing pollution generated by chemical products, agricultural waste, or products that accumulate in the environment spending years for its degradability. The originality of this project is present in the use of the oregano stick, a natural product which supplies the physicochemical characteristics of conventional raw materials used in the manufacture of wood. Oregano was collected and dried to separate the leaves from the stick. The stick was then ground, sieved at 0.118 mm and 0.025 mm, and then treated with one of two binders. For treatment 1, three samples were prepared with varying lactic acid concentrations and stick quantities with the addition of 0.3 mL of 2,2 azobisiso-butyronitrile (AIBN) 1% by weight. In treatment 2, three samples were prepared with varying polyvinyl acetate concentrations, diluted in acetone, stirred, poured into a mold, and placed in an oven at a temperature of 90 °C for 36 h. Bending and compression mechanical tests were performed on all samples; the data were analyzed by one-factor analysis of variance and Tukey test. The sample that performed the best had a value of 1.148 mm and 0.77333 kN in mechanical resistance and less elongation in compression. This sample also had a value of 0.8183 and a kN of 0.1559 with a lower mean, meaning higher resistance to bending. This sample also had the best results from the Modulus of Rupture (MOR) test with a value of 5.9958 MPas/m2.

Parameters evaluation in the process of solid phase pulp sedimentation in technological units of beneficiation plants

The aim of the research is the analysis and modeling of the process of sedimentation of the solid phase of the pulp in the technological units of processing plants to assess the density of particles of crushed ore. The paper analyzes domestic and foreign experience; methods of mathematical modeling were used, as well as methods of mathematical statistics and probability theory for processing the results of experiments. Scientific novelty consists in developing and substantiating a method for estimating the density of crushed ore particles in the process of their sedimentation directly in the process units of beneficiation plants. Practical value consists in developing a methodology for determining the characteristics of the enriched raw materials, which make it possible to form the degree of grinding necessary for the full disclosure of mineral formations. It was proposed to use the density of ore particles as an indicator of changes in the quality characteristics of the ore received for beneficiation, which is determined on the basis of measurements of the attenuation of volumetric ultrasonic waves and Lamb waves propagating in the pulp and the wall of the technological sump that is in contact with it. These measurements must be synchronized with the results of measurements of the pulp level in the sump during its working operation. The proposed method makes it possible to dynamically correct the parameters of the model of a closed ore grinding cycle, depending on the quality characteristics of the feedstock, and thereby form the conditions for the full disclosure of inclusions of the useful component in the product entering the magnetic separation or flotation.

Sustainable application of coal fly ash: One-step hydrothermal cleaner production of silicon-potassium mineral fertilizer synergistic alumina extraction

Coal fly ash (CFA) is the main solid waste discharged from coal-fired power plants, a new method for preparing silicon-potassium mineral fertilizer using KOH hydrothermal treatment CFA was proposed to improve its comprehensive utilization rate and reduce its threat to ecological environment security. In this paper, the characteristics of CFA raw material and transformation residue were studied, the agricultural applicability of the process was verified by pakchoi planting experiments, and the effects of the silicon-potassium mineral fertilizer on soil physical-chemical characteristics were investigated. The results show that increasing the leaching temperature and time can improve the extraction rate of alumina from CFA, and the reaction rate is controlled by the mixing of interfacial chemical reaction and solid product layer diffusion. The CFA raw material was hydrothermally leached at 280 g/L K2O 200 °C for 1 h, in which the Al2O3 extraction rate was 27.46%. The main component of the transformation residue was potassium aluminum silicate hydrate, which is the main component of the silicon-potassium mineral fertilizer, and the effective K2O and SiO2 content is 25.07% and 34.56%. The application of CFA residue can effectively improve the fertility and productivity of the soil, providing nutrients for the growth of pakchoi and improving the soil quality. This research provides theoretical guidance for the preparation of silicon-potassium mineral fertilizer using CFA and has the potential for practical production, which is important for the resourceful use of CFA and its application in agriculture.

Development of a mathematical model for predicting the quality of semi-smoked sausages made from second-grade beef

The article is devoted to the development of a mathematical model for predicting the quality of semi-smoked sausages from beef of the 2nd grade. The use of meat raw materials below 1st grade in the production of high quality sausages due to enrichment with new natural ingredients represents the relevance of the research. The use of enzymes and buckwheat flour in the production of meat products contributes to the improvement of the quality characteristics of the initial meat raw material, increasing the nutritional and biological value of finished products. The results showed that the addition of the enzyme "Protepsin" intensifies the processes of hydrolysis of proteins of connective tissues of beef, increases the moisture-binding ability of model minced meat. It was found that in model minced meat with the use of enzyme in the amount of pH reaches the optimum value in a shorter time. At addition of buckwheat flour the optimum value of moisture-binding capacity is established. The article shows that increasing the amount of buckwheat flour in the formulation of model minced meat more than 6 % leads to an increase in moisture-binding capacity, but at the same time organoleptic characteristics deteriorate significantly. The results obtained during the experiment showed that the enzyme «Protepsin» can be recommended to improve the functional and technological indicators of minced meat and ready semi-smoked sausages and accelerate the maturation process of raw materials. In this paper the object of the study is model minced beef minced meat of 2 grades, enzyme «Protepsin», buckwheat flour.

Production and use of AAC in India

AbstractAAC was introduced in India in 1970s. However, there were only three factories producing a total of less than 1 million m3/year till 2008. Post 2009, AAC blocks gained popularity due to their numerous advantages, including high strength, excellent insulation properties, fire resistance, sound absorption, and cost advantages over alternate walling materials. The use of AAC blocks has also been promoted by the Indian government's emphasis on sustainable and eco‐friendly building materials. The number of factories increased rapidly to over 150 factories with a cumulative capacity of over 25 million m3/year in 2022 (a growth of 25 times in nearly 15 years). Despite the rapid growth, the share of AAC in walling industry in India is still in the range of 5%–6%. There is still a lot of room for the industry to grow. AAC reinforced products have also been recently re‐introduced in India, though it is still at a very nascent stage and the share of AAC reinforced products in total AAC sales is less than 1%. More than 95% of AAC industry in India uses fly ash as the primary raw material and faced challenges initially to stabilize the design mix, due to variations in raw material characteristics. The rapid growth also resulted in improper implementation of standards and processes, during both production and application. The primary issue on the production side has been lower compressive strength and higher corner chipping. The main challenge on the application side has been improper techniques such as non‐usage of reinforcement beams and fiber meshes, which led to cracks in masonry subsequently. Now, the AAC industry is working together with applicators and researchers to overcome these challenges, in order to consolidate the gains and continue the rapid growth trajectory to become the preferred walling material.

Comparative Study of Anatomical and Diagnostic Features of the Leaves of the European Dewberry (&lt;i&gt;Rubus caesius&lt;/i&gt; L.), Allegheny Blackberry (&lt;i&gt;R. allegheniensis&lt;/i&gt; Porter) and European Blackberry (&lt;i&gt;R. nessensis&lt;/i&gt; Hall)

Introduction. Expansion of the nomenclature of raw materials, including herbal substances, is one of the tasks of the development of the pharmaceutical industry. As an example of a potential and affordable medicinal plant raw material, we can offer the leaves of European dewberry with a proven anti-inflammatory, hypoglycemic, antimicrobial activity. Medicinal plant – European dewberry (Rubus caesius L.) belongs to the genus Rubus L., which includes many species, often difficult to distinguish between each other. For complete pharmacognostic characteristics of medicinal plant raw materials, microscopic examination is necessary.Aim. To carry out a comparative microscopic analysis of the leaves of R. caesius L., R. allegheniensis Porter and R. nessensis Hall to establish anatomical and diagnostic characters.Materials and methods. Leaf samples were collected on the territory of Moscow and the Moscow region in 2021-2022. Microscopic structures were analyzed using a Leica DM1000 light microscope (Germany) with a 10x/20 eyepiece and 10x/0.25 and 40x/0.65 lenses.Results and discussion. A comparative analysis of the anatomical and diagnostic structures of the leaves of the Rubus caesius L. (European dewberry) and its related species has been carried out. The size and frequency of occurrence per 1 mm2 of simple and glandular hairs and stomata were investigated, the type of stomatal apparatus was established, the shape of epidermal cells and crystalline inclusions in the mesophyll were considered. Conclusion. As a result of the study, differences in the anatomical structures of the leaves of three types of blackberries were revealed. Anatomical and diagnostic characters of Rubus caesius L. leaves have been established, which are indicators of the identification of this raw material, including: the presence of simple one-celled fused at the base trichomes, abundant leaf pubescence (especially on the abaxial epiderm), a large number of stomata (106 ± 37 per 1 mm2), the sinuous shape of epidermal cells, cubic crystals of calcium oxalate in the mesophyll.

In-line Raman spectroscopy for characterization of an industrial poultry raw material stream

In this work, we evaluated the feasibility of Raman spectroscopy as an in-line raw material characterization tool for industrial process control of the hydrolysis of poultry rest raw material. We established calibrations (N = 59) for fat, protein, ash (proxy for bone) and hydroxyproline (proxy for collagen) in ground poultry rest raw material. Calibrations were established in the laboratory using poultry samples with high compositional variation. Samples were measured using a wide area illumination Raman probe at varying working distance (6 cm, 9 cm, 12 cm) and probe tilt angle (0°, 30°) to mimic expected in-line variations in the measurement situation. These moderate variations did not significantly affect performance for any analytes. The obtained calibrations were tested in-line with continuous measurements of the ground poultry by-product stream at a commercial hydrolysis facility over the course of two days. Measurements were acquired under demanding conditions, e.g. large variations in working distance. Reasonable estimates of compositional trends were obtained. Validation samples (N = 19) were also reasonably well predicted, with RMSEPcorr = [0.14, 1.37, 2.36, 1.51]% for hydroxyproline, protein, fat and ash, respectively. However, there were indications that further calibration development and robustification of pre-processing would be advantageous, particularly with respect to hydroxyproline and protein models. It is the authors’ impression that with such efforts, potentially in combination with development of practical measurement setup, the use of Raman spectroscopy as a process control tool for the hydrolysis of poultry rest raw materials is within reach.

Biofuel Production Through Co-Pyrolysis Process By Utilizing Waste Raw Materials Of Palm Oil and Plastic Waste

Oil, natural gas, and coal are non-renewable fossil energy sources. The limited availability of non-renewable fossil fuels has prompted countries worldwide to develop technologies that harness energy from renewable sources. One of these renewable energy sources is biofuel, which includes bioethanol and biodiesel. Currently, the Co-Pyrolysis method has been widely developed for waste processing. The Co-Pyrolysis method aims to extract energy content from a mixture of raw materials. The varying percentage of raw material mixtures can significantly influence the resulting products. Obtaining the characteristics of raw materials, the differences in temperature distribution graphs for each percentage of the raw material mixture, and achieving optimum product yield are the objectives of the Co-Pyrolysis process. Based on the data from the heating process, it has been found that an excellent product can be obtained from heating a mixture of TKKS (30%) and PS (70%) at 500 °C for 1 hour, resulting in a product yield of 68%.

Investigation of the low-temperature exposure effect on the water activity of food products

Introduction: The activity of water is an integral characteristic of the moisture condition in a product, by which one can assess the correctness of various technological processes, as well as predict the shelf life of the product. Existing studies on the activity of water in food products were conducted mostly for the positive temperature range. Little attention was paid to the study of the effects of low-temperature exposure on water activity.Purpose: The article is devoted to the study of water activity in food products at various temperatures. Such an approach will allow predicting the shelf life of food products and optimizing the development of methods for controlling the functional and technological characteristics of food raw materials.Materials and Methods: The objects of research were: beef chilled according to GOST R 52427-2005, chilled pork, chilled mutton, fresh cucumbers, fresh carrots, fresh tomatoes, fresh parsley greens, dill greens, green onion greens. Two installations were used to analyze the water activity in the research objects: designed at the Kuzbass State Agricultural Academy, and the LabSwift-aw water activity analyzer. Experiments were conducted for fresh, chilled, and frozen products at various temperatures.Results: A design of a homemade installation that can be used to measure water activity is presented. The accuracy of this installation's measurements is experimentally proven. An analysis of water activity in fresh, chilled, and frozen products has been conducted. The water activity of fresh products was within the range of 0.954-0.995. It was found that with the same moisture content, the water activity can vary slightly, which is due to the difference in the chemical composition of the product and the salt content. It was established that chilling products from 22 to 6°C leads to a decrease in water activity by an average of 2%. Freezing to a temperature of -5°C results in a further reduction of water activity by an average of 0.03 units. Lowering the freezing temperature from -5°C to -10°C, -20°C, -30°C, and -40°C results in a reduction of water activity by an average of 0.04, 0.07, 0.06, and 0.05 units, respectively. Based on experimental data, mathematical dependencies of water activity on the freezing temperature for all studied products were derived.Conclusion: Water activity has important theoretical and practical significance, and the results of the research can be useful in predicting the shelf life of food products and developing methods to control the functional and technological characteristics of food raw materials.