Multilayer Plastic Research Articles

Shelf life modelling of kaşar cheese packaged with potassium sorbate, nisin, silver substituted zeolite, or chitosan incorporated active multilayer plastic films

The effects of active films on the stability of kaşar cheese stored at 5 °C, 15 °C, and 25 °C were investigated regarding microbial quality, physicochemical, and textural properties. The antimicrobials incorporated into the films (LDPE/polyamide/LDPE+2% antimicrobials) were potassium sorbate (PS-film), nisin (N-film), chitosan (CTS-film), or silver substituted zeolite (AgZeo-film). Shelf life, activation energy, and temperature quotient were also calculated. According to total mesophilic aerobic bacteria (TMAB) count, active films successfully inhibited microbial growth. The lowest growth rate for TMAB count of the samples was found in AgZeo-film, followed by N-film. CTS-film was more effective in controlling total yeast and mould count. PS-film showed some inhibition ability in both counts, but not as much as the other active films. Hence, antimicrobial agents incorporated into active films should be chosen considering main deteriorative microorganism in food being packaged. The active films improved shelf life of kaşar cheese by lasting the lag times of microorganisms.

An overview of polymer identification techniques in recycling plants with focus on current and future challenges

With the European Green Deal, the European Commission is clearly addressing environmental and climate related topics. Amongst other measures, the circularity of materials and the necessity for recycling are being addressed. According to the OECD the world's recycling rate for plastics in 2019 only reached 9%. For successful plastics recycling, however, it is necessary to ensure efficient sorting of wastes. The higher the separation efficiency and the purity of the sorted plastics, the higher the quality of the recycled material. Therefore, efficient plastics detection techniques are vital for the recovery and recycling process. Plastics identification poses several challenges such as the large variety in plastic types and additives, material contamination or multi-layer plastics and composites, to mention a few. The state-of-the-art detection of polymers relies on density as well as material identification based on infrared, laser-based and x-ray fluorescence methods. Recent technologies use image recognition and sensor fusion or target recognition through a marking system to improve the sorting quality. In future, detection techniques will have to deal with even further challenges, such as new plastics (such as bioplastics) and plastic blends. This paper provides an overview of the state-of-the-art techniques found in industrial recycling plants, their potentials and limitations, as well as the techniques currently under investigation for facing current and future challenges.

Shelf Life and Safety of Vacuum Packed HPP-Treated Soaked Cod Fillets: Effects of Salt Content and Multilayer Plastic Film

High microbiological quality standards, food safety, and environmental sustainability represent crucial topics in food production chains. For this reason, fish industries, which import salted and seasoned fish products from supplier countries, i.e., Norway, Denmark, USA (Alaska State), etc., have tried to reduce the salt content of each carton during transportation (reducing carbon emissions and the weight of major quantities of transported fish). In the present study, 360 differently processed fish fillet samples, belonging to the species Gadus macrocephalus caught in FAO zone 67, were microbiologically and chemically screened. This study aimed to provide original data concerning the applicability of sustainable solutions investigating the combined effects of salt content reduction combined with new recyclable multilayer plastic film packaging (vacuum skin packaging with two different oxygen transmission rate values). The microbiological results showed no substantial changes comparing the two differently salted products, highlighting their high hygienic characteristics which were also observed in their chemical analysis. The shelf life evolutions (comparing the two different studied plastic films) highlighted that, after 35 days from HPP treatments, bacterial loads gained high values, over 6 log cfu/g. This study highlights that, compared to the currently used plastic films, the results of the new and sustainable multilayer plastic films show that they can provide safe food matrices in combination with HPP technologies. Therefore, this preliminary investigation brings closer attention to alternative and environmentally sustainable production systems with their designs based on the multidisciplinary approach of food production systems.

Quantifying the environmental benefits of a solvent-based separation process for multilayer plastic films

The STRAP process can provide environmental benefits over the virgin film production process. We identified the polymers and process units that have the highest environmental impact.

A STUDY OF AVAILABLE TECHNOLOGY FOR RECYCLING LOW VALUE PLASTIC IN INDONESIA

Plastic has been an essential part of our daily life. However, the increasing plastic consumption has led to an increasing land and water contamination by said plastics. The Indonesian government has set five actions on managing marine plastic debris, one of them is by improving the plastic recycling system. Multilayer plastic was identified as a challenge to the plastic waste recycling. This is because there are differences in properties, such as melting point, which will cause difficulty in mechanical recycling. This study aims to create a mapping of available options to solve problems of low value plastic (LVP) waste in Indonesia and to assess the readiness level of key aspects in implementing the available options. Interviews was done with twelve experts on the field of material or energy recovery from plastic waste, especially LVP, to find the available technology options which include but not limited to their primary features, readiness status and feasibility, and potential market size. The evaluation was based on a set of criteria in technology, environment, social, and economy viewpoints. Three top low hanging options are conversion to plastic lumber, refuse derived fuel (RDF) production, and conversion to plastic products. All the three processes have mature technology and local availability. The challenges include a good branding and marketing strategy to expand market, endorsement, and recognition from government, including recycle content standard and more cost-effective collection. Further investigation has to be done for RDF utilization in industrial boilers. More promotion and introduction of recycled products have to be performed in order to create market to allow a sustainable recycling industry.

Co-combustion of multilayered plastic waste blend with biomass: Thermokinetics and synergistic effect

Improper management of inert plastic waste causes severe threats to the environment and leads to global climate change. The thermochemical combustion process adequately converts the plastic waste into a potential energy resourceas refuse-derived fuel (RDF), however, to get maximum energy yield, it is required to optimize the combustion process. Therefore, the physio-chemical and thermal characteristics of multilayer plastics (MLPs) and their blends with different biomassare determined under non-isothermal conditions. Five representative samples S1 to S5 which includes MLPs and their blend with biomass were selected for this study. Thermogravimetric analysiswas used to performthe combustion process with temperatures ranging from 30 °C to 1000 °C. It is noted that sample S1 has 77.87 % volatile matter, 8.30 % ash content, and 0.01 % sulfur and shows ahigher energy potential of 27.10 MJ/kg with minimum environmental emissions, demonstrating good agreement with theRDF I category. Thermo-kinetic parameters using the Coates-Redfern integral methoddemonstrated that the co-combustion follows a diffusion–reaction mechanism. The sequence of activation energy (Ea) and Gibbs energy (ΔG) follows in the order of S4 > S5 > S1 > S2 > S3. Moreover, the maximum Ea and ΔG required for the decomposition of these samples are in the range of 101–142 kJ/mol and 115–120 kJ/mol, respectively. It is concluded that the optimized S1 sample shows similar characteristics to conventional fuels and can be directly co-processed in cement industries or waste-to-energy plants. The obtained results can help in modeling and designing the thermochemical reactor for bench-scale operations.

Comprehensive investigation on physical and chemical properties of γ‐irradiated multilayer PE/EVOH/PE film: A multiscale approach

AbstractThe study evaluates findings on the impact of γ‐irradiation on the single‐use, multilayer plastic film that is manufactured for the biotechnological and biopharmaceutical environments. It is comprised of a multilayer film that offers durability and gas (O2, CO2 and H2O) shielding properties. Polyethylene (PE) and ethylene vinyl alcohol (EVOH) are the parts within this film, which as a whole, is PE/EVOH/PE. The impact of γ‐irradiation on the nonirradiated and γ‐irradiated (from 30 kGy up to 270 kGy) PE multilayer film is investigated by colorimetry measurement, Fourier transform infrared and Raman spectroscopies, pH measurement, ion chromatography and conductivity measurement, tensile tests, X‐ray photoelectron spectroscopy, differential scanning, and oxygen and water vapor transmission rate. AComDim and Principal Components Analysis are two chemometric tools that are utilized to understand both physical and chemical changes, along with the main factors contributing to polymer degradation in the PE multilayer film while under γ‐irradiation.

Disinfestation of wheat seed from Sitophilus granarius (L.), S. oryzae (L.), and Rhyzopertha dominica (F.) by packing under vacuum in high-barrier multi-layered plastic bags

Conditioning under low-oxygen modified atmosphere in sealed enclosures, containers or bags is widely used for the disinfestation of grain from insect pest species. The effect of hermetic vacuum storage on the survival of primary insect pests of cereals still lacks relevant documentation. To enhance knowledge on this topic, a pilot scale experiment was undertaken. Prior to the study, batches of wheat seeds were infested by some of the most harmful insects of stored cereals, Sitophilus oryzae, S. granarius, and Rhyzopertha dominica, in order to obtain infested seed samples by all development stages. Then, 5-kg sound wheat seed lots were placed inside multilayer aluminium-plastic flexible bags and 200 g of previously infested seeds were included before vacuum packing the bags at depression levels: 30, 50 or 70 kPa. In addition to storage at an average temperature of 25.8 °C, survival rate and progeny production of insects were checked at regular time intervals after opening a series of bags. After adult recovery by sieving, the 200 g-samples were incubated for 42 d at 25.8 °C for hidden stages recovery. The exposure time for 99% reduction of survival rate and progeny production (LT99) by S. oryzae and S. granarius, at 70 kPa depression level, was observed after 37.5 and 31 d exposure, respectively. For R. dominica, LT99 was assessed at 63.5, 75.6 and 88.5 d at 70, 50 and 30 kPa depression level, respectively. Rhyzopertha dominica was observed much more tolerant than the two weevil species, especially when depression level was more than 50 kPa. This species was able to produce progeny under vacuum. The origin of the differences in susceptibility between the weevils and the lesser grain borer in relation to storage under vacuum inside flexible high-barrier multilayer aluminium-plastic bags are discussed.

Polypropylene-based Multilayer Plastic Waste Utilization on Bitumen Modification for Hot-Mixed Asphalt Application: Preliminary Study

Plastic waste that has not been appropriately managed has caused concern for various stakeholders and has a negative impact on the environment. A way to minimize this issue is by promoting a circular economy through recycling. Despite this, many plastic wastes cannot be economically recycled; one of them is multilayer plastics due to the difficulty in sorting out the various types of materials contained in the layers. As an alternative, it may be possible to utilize multilayer plastic as a bitumen mixture; this method may avoid the separation process entirely. Bitumen is a component of asphalt, which is crucial to the construction of infrastructure. Plastics can potentially enhance the properties of modified bitumen, and they would assist in enhancing the quality of the asphalt. The aim of this study is to examine the impact of multilayer waste plastics on bitumen fabricated by the hot-mixing process. To enhance the compatibility between hydrophobic plastic and hydrophilic bitumen, lignin was used as a compatibilizer. The properties of bitumen with 3, 4, and 5 wt.% multilayer plastic and mixing times of 15, 30, and 45 minutes were evaluated. Accordingly, surface, chemical, thermal properties, and morphology were evaluated using sessile drop tests, Fourier Transform Infrared, thermogravimetry analysis, and scanning electron microscopy.

Development and Evaluation of Sorghum and Little Millet Based Ladoo

Millets are called Nutri-cereals which are nutritionally superior when compared to that of staple cereals like rice and wheat and have numerous health benefits in improving the overall health of consumers. In spite of their multiple health benefits, millets are only consumed by people who are of low income group. The present study was done to develop and analyse the nutritional value, physiochemical properties and shelf life studies of millet ladoo as readymade snack which is developed through standardization process by blending the major millet i.e Sorghum (Sorghum bicolor) and minor millet i.e. Little millet (Panicum sumatrense), Tamarind kernel powder (Tamarindus indica), Cardamom (Elettaria cardamomum), Bengal gram flour (chick pea) ghee and palm jaggery powder. Millet ladoo that was highly accepted by thirty semi-trained panel members through nine point hedonic scale by formulating sorghum, little millet and other ingredients showed total carbohydrates, protein, fat and fibre about 55.68, 7.54, 20.2 and 2.88% respectively. The sensory evaluation of the acceptable ladoo revealed that the texture, appearance, color, aroma, taste and all quality parameters were in acceptable range during storage. The product shelf life was found to be 30 days with addition of preservative i.e. food grade potassium sorbate followed by packaging of millet ladoo by using polyethylene terephthalate tray as primary packaging material and multilayer plastic laminate pouch as a secondary packaging material. The shelf life of millet ladoo was 15 days without addition of preservative when packed in polyethylene terphthalate tray that was placed in multilayer plastic laminate pouch at room temperature. The sensory parameters of millet ladoo packed in polyethylene terphthalate tray without multilayer plastic laminate pouch was not acceptable for further studies. The work done was an attempt to develop value added products of major and minor millets and increase consumption of millet products for better nutrition of consumers.

A Study on Recycled Polymers Recovered from Multilayer Plastic Packaging Films by Solvent‐Targeted Recovery and Precipitation (STRAP)

AbstractMultilayer plastic film use increased in multiple packaging applications due to its versatility and overall increased performance over monolayer structures. However, the performance gains from multiple layers also make recycling difficult because they contain multiple polymers that can be immiscible and burdensome to traditional mechanical recycling operations. A possible solution is the solvent‐targeted recovery and precipitation (STRAP) process, but the effect on the retrieved polymer is still unknown. The STRAP process is applied to two different multilayer films and samples of recovered polymers are evaluated for physical, molecular, and thermal properties. Changes in the molecular weight are not significant, but differences in thermal properties are reported along with the coprecipitation of different polymers. Solvent retention in the polymer matrix from STRAP reduced the glass transition temperature of samples, but enhanced drying recovered it. Heavy metals, such as Cd, Cr, and Pb are not detected, indicating regulatory compliance for different applications.

Diffusional and antimicrobial behaviors of some antimicrobial agents in active multilayer plastic films

AbstractIn this study, diffusional and antimicrobial properties of the active‐multilayer plastic films (LDPE/polyamide/LDPE‐2% antimicrobial agent) were assessed. To understand the diffusion of antimicrobials from the active plastic films containing nisin, potassium sorbate, silver substituted zeolite, or chitosan, the active‐multilayer plastic films has been put in different food simulating solutions. The food simulating solutions had various pH (3.0–7.0) and water activity (0.65–0.95) levels and were incubated at various storage temperatures (5–25°C). The release experiments for the combinations of the factors were set according to three factors face‐centered central composite design (CCF) of the response surface methodology (RSM). The diffusion rate constant (D) was calculated using Fick's law approach. The D of nisin and silver substituted zeolite was affected by pH or temperature, while aw is not a significant factor. However, Dps was found to be the highest and depended on all factors (4.45–10.04 × 10−14 cm2/s). Furthermore, no chitosan release was detected from the film matrix. The antimicrobial effectiveness of the films against microorganisms that were Staphylococcus aureus, Escherichia coli, Candida albicans, and Aspergillus niger varied according to the film type, which was verified by a challenge test on the kaşar cheese surface. Moreover, nisin and silver substituted zeolite incorporated films showed great potential to inhibit bacteria, yeast, and molds. All active films, which were studied, had featured tasks for being active food packaging material and diffused in allowance limits.

Effect of Cold Plasma Treatment on Physical Properties of Multilayer Plastics for Polymer Asphalt Applications

Multilayer plastic waste continues to increase due to the ever-growing consumption and needs of the global citizen and is one of the most challenging types of waste to recycling because of its nature. The accumulation and indiscriminate disposal of waste can pose a potential risk of environmental problems. A solution that can be implemented is to mix bitumen and waste polymer as asphalt manufacturing. Despite its advancement in research, many potential parameters are still to be discovered to achieve optimal results. Through cold plasma treatment, a surface treatment may occur at the multilayer polypropylene that causes the change from hydrophobic to hydrophilic properties. Treating the polymer with cold plasma will provide good hydrophilic properties without changing the overall chemical and thermal properties of the sample. This will result in an alternative aggregate for the bitumen for asphalt manufacturing. Bitumen coupled with the addition of plastic still provides an optimal hardness and ductility, meanwhile having a more economically viable manufacturing process than other processes.

A Journey from Processing to Recycling of Multilayer Waste Films: A Review of Main Challenges and Prospects.

In a circular economy context with the dual problems of depletion of natural resources and the environmental impact of a growing volume of wastes, it is of great importance to focus on the recycling process of multilayered plastic films. This review is dedicated first to the general concepts and summary of plastic waste management in general, making emphasis on the multilayer films recycling process. Then, in the second part, the focus is dealing with multilayer films manufacturing process, including the most common materials used for agricultural applications, their processing, and the challenges of their recycling, recyclability, and reuse. Hitherto, some prospects are discussed from eco-design to mechanical or chemical recycling approaches.

Numerical analysis of two-layered isothermal calendering of viscoplastic and Newtonian fluids with different viscosity ratios

Co-extruded multi-layer plastic sheets and polymer structures formed by calendering process or by cold rolling are widely used in the packaging industry and thin-film transistor manufacturing. The different materials are extruded from separate extruders into the single sheet die which delivers a multi-layer sheet with uniform layer thickness at die exit. This multi-layer sheet is then stretched between counter-rotating rolls to obtain final uniform multi-layer sheet. There are many factors which can influence this process. In this article, calendering a single layer Newtonian or Non-Newtonian material has been extended to analyze a two-layer calendering process for an incompressible Viscoplastic and Newtonian fluids as upper and lower layers with different viscosity ratios. To simplify the equations of motion, the lubrication approximation theory is used. The expressions of non-dimensional pressure gradient, pressure and velocity distribution of both layers are obtained analytically by using proper no slip boundary conditions and dimensionless variables. The dimensionless detachment point is approximated by Regula-Falsi (false position) method. The important engineering factors including detachment point, calendered sheet thickness, roll separation force, power input by rolls, torque on each roll, and adiabatic temperature are all computed. In addition, how the viscosity ratios and viscoplastic casson parameter affect these factors have been investigated. Moreover all established results in literature for single layer calendering Newtonian fluids are also validated at casson parameter β tending towards infinity.

Sustainability and Life Cycle Assessment of Thermoplastic Polymers for Packaging: A Review on Fundamental Principles and Applications

AbstractThis article presents recent developments in the use of life cycle assessment (LCA) for evaluating the sustainability of thermoplastics, including multilayer plastics packaging and comparisons with other packaging materials. Due to increasing environmental awareness, thermoplastics, despite their superior properties, are being increasingly substituted with other materials due to their fossil‐based origin and non‐biodegradability. While the use of biodegradable and bio‐based thermoplastics contributes to overcoming these limitations, there are still challenges associated with the environmental effects of the cultivation phase of agricultural resources and the infrastructure and costs required for composting. Therefore, a quantitative evaluation of the environmental performance of various thermoplastics and their packaging applications over their complete life cycle compared with other conventional materials like paper and glass, using LCA, is imperative for understanding the role of thermoplastics in sustainable development. LCA is also vital for selecting the material, process, and waste management technique best suited for sustainability without compromising the product quality. In summary, the fundamental knowledge of LCA and critical assessment of key literature on LCA of thermoplastic materials and their packaging applications, will provide direction for future advances in the field of sustainable polymeric materials and the socio‐economic aspects of sustainability.

Nonlinear continuum mechanics of thick hyperelastic sandwich beams using various shear deformable beam theories

In this study, the time-dependent mechanics of multilayered thick hyperelastic beams are investigated for the first time using five different types of shear deformation models for modelling the beam (i.e. the Euler–Bernoulli, Timoshenko, third-order, trigonometric and exponential shear deformable models), together with the von Kármán geometrical nonlinearity and Mooney–Rivlin hyperelastic strain energy density. The laminated hyperelastic beam is assumed to be resting on a nonlinear foundation and undergoing a time-dependent external force. The coupled highly nonlinear hyperelastic equations of motion are obtained by considering the longitudinal, transverse and rotation motions and are solved using a dynamic equilibrium technique. Both the linear and nonlinear time-dependent mechanics of the structure are analysed for clamped–clamped and pinned–pinned boundaries, and the impact of considering the shear effect using different shear deformation theories is discussed in detail. The influence of layering, each layer’s thickness, hyperelastic material positioning and many other parameters on the nonlinear frequency response is analysed, and it is shown that the resonance position, maximum amplitude, coupled motion and natural frequencies vary significantly for various hyperelastic and layer properties. The results of this study should be useful when studying layered soft structures, such as multilayer plastic packaging and laminated tubes, as well as modelling layered soft tissues.

Wood plastic composites (WPCs) from multilayer packaging wastes and rHDPE as pallets for green industry

People are becoming more aware of plastic pollution. Consumers, researchers, and manufacturers are seeking ways to reduce their contribution to the problem. Management of plastic wastes has still been severely environmental problems, especially those with multilayer or multicomponent structures due to the difficulty in recycling process. According to the concept of circular economy, this research aimed to overcome these problems by recycling the multilayer plastic film wastes after use from consumers (classified as post-consumer recycled resin, PCR) and transforming those into high-value products. In this work, Wood Plastic Composites (WPCs) made from mixtures of multilayer packaging wastes (PCRs), recycled high density polyethylene (rHDPE) and wood powders were studied in order to be used as pallets in green industry. Studied factors affecting WPC properties included PCR types (linear low density polyethylene (LLDPE), multilayered oriented polyamide (OPA)/PE and polyethylene terephthalate (PET)/PE films) and rHDPE:PCR weight ratios (40:5, 35:10, 30:15 and 25:20). WPC samples were compounded by a two-roll mill and then shaped into samples by a compression molding machine. Morphological, mechanical and thermal properties of WPCs were examined. From SEM study, it was revealed that wood powders and fibers were well distributed and randomly oriented in WPCs. Both PCRs (OPA/PE and PET/PE) were partially melted because the processing temperatures were below the crystalline melting temperatures of OPA and PET. PCR orientation in WPCs was aligned with the compression direction. Mechanical properties of WPCs from OPA/PE were similar to those of WPCs from PET/PE. WPCs from rHDPE:PCR weight ratios of 40:5 and 35:10 had good mechanical properties which passed the industrial target values. Optimum formulas were then used to form WPC samples by extrusion technique and fabricated into WPC pallets. It was found that the WPC pallets from wastes showed promising properties with high potential to replace conventional pallets in warehouses and industrial transport for green industry.

Conversion of plastic waste into fuel oil using zeolite catalysts in a bench-scale pyrolysis reactor.

Catalytic pyrolysis of mixed plastic waste to fuel oil experiment was tested with ZSM-5 zeolite (commercial and synthesized) catalysts along with other catalysts. The ZSM-5 zeolite catalyst was effectively produced using a hydrothermal technique via metakaolin as an alumina source. The catalytic pyrolysis of different types of plastic (single and multilayer) wastes in the presence of various catalysts was tested with a bench-scale pyrolysis setup with 2 kg per batch capacity. Polyolefin based plastics (low-density polyethylene, high-density polyethylene, and polypropylene), multilayer plastics such as biaxial oriented polypropylene (BOPP), metalized biaxial oriented polypropylene layers (MET BOPP), polyethylene terephthalate (PET), metalized polyethylene terephthalate (MET/PET), polyethylene terephthalate combined polyethylene (PET/PE), and mixed plastic waste collected from the corporation sorting center were pyrolyzed in a batch pyrolysis system with 1 kg feed to determine the oil, gas and char distributions. The performances of commercial ZSM-5 and lab synthesized ZSM-5 catalysts were compared for the pyrolysis of non-recyclable plastic wastes. Other commercial catalysts including mordenite and gamma alumina were also tested for pyrolysis experiments. The gross calorific value of oil obtained from different combinations of multilayer packaging waste varied between 10 789–7156 kcal kg−1. BOPP-based plastic waste gave higher oil yield and calorific value than PET-based plastic waste. Sulfur content present in the oil from different plastic wastes was measured below the detection limit. The synthesized ZSM-5 zeolite catalyst produced a maximum oil output of 70% and corresponding gas and char of 16% and 14% for LDPE plastic. The strong acidic properties and microporous crystalline structure of the synthesized ZSM-5 catalyst enables increased cracking and isomerization, leading to an increased breakup of larger molecules to smaller molecules forming more oil yield in the pyrolysis experiments. Residual char analysis showed the maximum percentage of carbon with heavy metal concentrations (mg kg−1) in the range of viz., chromium (15.36–97.48), aluminium (1.03–2.54), cobalt (1.0–5.85), copper (115.37–213.59), lead (89.12–217.3), and nickel (21.05–175.41), respectively.

THE ISSUE OF HISTOLOGICAL IDENTIFICATION OF М-CELLS IN THE PEYER'S PATCHES OF ALBINO RAT SMALL INTESTINE.

The aim: Based on the above cytological signs of M-cells, we set the goal of more detailed clarification of some of their topological relationships with other enterocytes in the follicle-associated epithelium of Peyer's patches of albino rat small intestine. Materials and methods: 10 mature albino male rats weighted 200,0±20,0 g were involved into the study. Anatomical dissection with the sampling of the sections of the small intestine containing Peyer's patches was carried out with subsequent embedment of the latter into paraffin blocks and making of serial histological sections of 4 μm thick in the cross-section of the small intestine, followed with hematoxylin-eosin staining. The specimens were studied and documented on the "Konus" light microscope equipped. Morphometric characteristics of the specimen tissue structures were studied using the Sigeta X 1 mm/100 Div.x0.01mm stage micrometer. Results: The findings of the study revealed enterocytes with phagocytic properties found in the lymphoid-associated epithelium of Peyer's patches of the small intestine of albino rats. Moreover, if they are clearly visualized at the light-optical level, then M-cells are poorly recognizable, which is consistent with a similar assessment made by other authors. Conclusions: Given this, the issue on the topology and functional purpose of M-cells remains uncertain to date and, thereby, the prospect of further research is being outlined, which, in our opinion, can be successful using the method of stereomorphological analysis. For this purpose, multilayer plastic reconstruction methods can be used for serial semi-thin sections of Peyer's patches embedded in epoxy resin, according to the requirements of transmission electron microscopy.