Search Results (96)

Low-commercial-value natural pistachios (broken, closed, or immature) can be revalorised through oil extraction, obtaining a high-quality oil and partially defatted flour as by-product. This study evaluated the techno-functional and nutritional properties of the flours obtained by hydraulic press (HP) and single-screw press (SSP) systems, combined with pretreatment at 25 °C and 60 °C. The extraction method significantly influenced flour’s characteristics, underscoring the need to tailor processing conditions to the specific technological requirements of each food application. HP-derived flours presented lighter colour, greater tocopherol content, and higher water absorption capacity (up to 2.75 g/g), suggesting preservation of hydrophilic proteins. SSP-derived flours showed higher concentration of protein (44 g/100 g), fibre (12 g/100 g), and minerals, and improved emulsifying properties, enhancing their suitability for emulsified products. Pretreatment at 25 °C enhanced functional properties such as swelling power (~7.0 g/g) and water absorption index (~5.7 g/g). The SSP system achieved the highest oil extraction yield, with no significant effect of pretreatment temperature. The oils extracted showed high levels of unsaturated fatty acids, particularly oleic acid (~48% of ω-9), highlighting their nutritional and industrial value. The findings support the valorisation of pistachio oil extraction by-products as functional food ingredients, offering a promising strategy for reducing food waste and promoting circular economy approaches in the agri-food sector. Full article

Perilla seed has long been recognized in traditional diets for its health-promoting properties, but its potential role in hair loss prevention remains underexplored. This study compared three extraction methods—maceration (MAC), screw pressing (SC), and supercritical fluid extraction (SFE)—to determine their efficiency in recovering bioactive compounds and their effects on androgenetic alopecia (AGA)-related pathways. The SFE extract contained the highest levels of polyunsaturated fatty acids and tocopherols, while MAC uniquely recovered a broader range of polyphenols. Among all extracts, SFE-derived perilla seed extract showed the most consistent biological effects, promoting proliferation of human hair follicle dermal papilla cells (HFDPCs) by 139.4 ± 1.1% at 72 h (p < 0.05). It also reduced TBARS and nitrite levels in HFDPCs to 66.75 ± 0.62% of control and 0.87 ± 0.01 μM, respectively, indicating strong antioxidant and anti-inflammatory effects. Importantly, the SFE extract significantly downregulated SRD5A1-3 and TGF-β1 expression—key genes involved in androgen-mediated hair follicle regression—outperforming finasteride, dutasteride, and minoxidil in vitro by approximately 1.10-fold, 1.25-fold, and 1.50-fold, respectively (p < 0.05). These findings suggest that perilla seed extract obtained via supercritical fluid extraction may offer potential as a natural candidate to prevent hair loss through multiple biological mechanisms. These in vitro results support its further investigation for potential application in functional food or nutraceutical development targeting scalp and hair health. Full article

A three-year optimization study was conducted at a mechanical biological treatment plant with the aim of enhancing organic fractions recovery from mechanically separated fine fractions (MSFF) of residual waste using a screw press. The study aimed to optimize key operating parameters for the employed screw press, such as pressure, liquid-to-MSFF, feeding quantity per hour, and press basket mesh size, to enhance volatile solids and biogas recovery in the generated press water for anaerobic digestion. Experiments were performed at the full-scale facility to evaluate the efficiency of screw press extraction with other pretreatment methods, like press extrusion, wet pulping, and hydrothermal treatment. The results indicated that hydrolysis of the organic fractions in MSFF was the most important factor for improving organic extraction from the MSFF to press water for fermentation. Optimal hydrolysis efficiency was achieved with a digestate and process water-to-MSFF of approximately 1000 L/ton, with a feeding rate between 8.8 and 14 tons per hour. Increasing pressure from 2.5 to 4.0 bar had minimal impact on press water properties or biogas production, regardless of the press basket size. The highest volatile solids (29%) and biogas (50%) recovery occurred at 4.0 bar pressure with a 1000 L/ton liquid-to-MSFF. Further improvements could be achieved with longer mixing times before pressing. These findings demonstrate the technical feasibility of the pressing system for preparing an appropriate substrate for the fermentation process, underscoring the potential for optimizing the system. However, further research is required to assess the cost–benefit balance. Full article

Mechanical–biological treatment plants face challenges in effectively separating organic fractions from residual municipal solid waste for biological treatment. This study investigates the optimization measures carried out at the Erbenschwang MBT facility, which transitioned from solely aerobic treatment to integrated anaerobic digestion using a screw press. This study focused on evaluating the efficiency of each mechanical pretreatment step by investigating the composition of the residual waste, organic fraction recovery rate, and screw press performance in recovering organic material and biogas to press water. The results showed that 92% of the organic material from the residual waste was recovered into fine fractions after shredding and trommel screening. The pressing experiments produced high-quality press water with less than 3% inert material (0.063–4 mm size). Mass balance analysis revealed that 47% of the input fresh mass was separated into press water, corresponding to 24% of the volatile solids recovered. Biogas yield tests showed that the press water had a biogas potential of 416 m³/ton VS, recovering 38% of the total biogas potential. In simple terms, the screw press produced 32 m³ of biogas per ton of mechanically separated fine fractions and 20 m³ per ton of input residual waste. This low-pressure, single-step screw press efficiently and cost-effectively prepares anaerobic digestion feedstock, making it a promising optimization for both existing and new facilities. The operational configuration of the screw press remains an underexplored area in current research. Therefore, further studies are needed to systematically evaluate key parameters such as screw press pressure (bar), liquid-to-waste (L/ton), and feed rate (ton/h). Full article

The long-term effectiveness of osseointegrated implants is heavily dependent on the short-term stability, primarily achieved immediately after surgery through a mechanical connection between the bone and the implant. The most common implant designs nowadays are straight and rely on screw or press-fit fixtures. Despite the promising results achieved by current transfemoral implants, the incidence of early failures and complications is still high. Starting from the hypothesis that a patient-specific approach could lead to better primary stability immediately post-surgery, this study aims to investigate the effect of implant design on primary stability. This was performed by analyzing two patient-specific implants, customized according to the medullary canal morphology, and a simple straight implant as the reference standard. To quantitatively assess the primary stability, a comparative computational analysis was conducted to examine the effective contact area, the relative micromotion, and the stress distribution at the interface between the bone and the implant stem during a static load-bearing exercise. The results showed that implants that follow the curvature of the residual femur provide lower micromotion values and a wider contact area, with a reduction of up to 30.4% and an increase of 10.8%, respectively, compared to the straight design, leading to a more homogeneous load distribution. Patient-specific prosthetic implants allow a more homogenous contact distribution that could lead to higher primary stability by reducing micromotion at the bone–implant interface concerning the straight profile, lowering the risk of loosening related to the short-term stability. Full article

The growing volume of plastic waste from end-of-life vehicles presents environmental concerns, driving efforts to integrate recycled plastics. This study investigates the possibility of using recycled plastic from automotive parts (painted and unpainted bumpers, fuel tanks) as a 10% filler in the core layer of three-layer particleboards (P) and evaluates its impact on physical properties (water absorption—WA and thickness swelling—TS), mechanical properties (internal bonding strength—IB, modulus of rupture—MOR, modulus of elasticity—MOE and screw driving torque—SDT) and volatile organic compounds—VOC emissions. The boards were produced using conventional hot-pressing technology and analyzed according to applicable standards. Based on the results, the density of the reference (P) was 0.72 g·cm⁻³, while wood–plastic composites ranged from 0.70 g·cm⁻³ to 0.72 g·cm⁻³. After 24 h, WA reached 40% for reference (P) and from 36.9% (for (P) containing unpainted bumpers) to 41.9% (for (P) containing fuel tanks). TS reached 18% for (P) and from 16.8% (for (P) containing unpainted bumpers and fuel tanks) to 18.1% (for (P) containing painted bumpers). Plastic is a hydrophobic material and it is assumed that by increasing the proportion of plastic filler in the particleboards, the WA and TS of prepared boards will decrease. From the point of view of mechanical properties, values for (P) containing plastic filler were slightly lower compared to reference (P). The lowest value of IB (0.39 MPa) were reached for (P) containing painted bumpers. Plastic surface treatment could interfere with adhesion between the plastic and adhesive, weakening the bond in the core layer. For this reason, is preferable to use unpainted fillers, which provide better adhesive properties and higher structural integrity. VOC emissions from wood components consisted primarily of monoterpenes such as α-pinene, 3-carene and limonene. Adding 10% plastic to the particleboard did not increase overall VOC emissions. On the other hand, combining wood and plastic particles resulted in a reduction in overall VOC emissions. The findings confirm that recycled automotive plastics can be effectively incorporated into particleboards, maintaining standard performance while reducing reliance on virgin wood materials, making them a viable and sustainable alternative for furniture and interior applications. Full article

The drive mechanism of a friction screw press consists of a screw transmission, a friction transmission and a belt transmission. Improper maintenance and axial misalignment of the screw spindle and the press are the main possible causes of screw spindle failure. The causes of the screw spindle fracture are investigated in the first part of this paper. A visual examination of the screw spindle is carried out in the first step. In the second step, the chemical composition and mechanical properties of the material from which the screw spindle of the drive mechanism is made are experimentally examined, and a metallographic examination of the fracture surfaces on the screw spindle is carried out using an electronic microscope. In the second part of this paper, the effects of screw spindle disturbances on the fracture are analyzed by applying the finite element method. The third part of this paper shows how the problem of repairing the damaged screw spindle of the drive mechanism of the friction screw press is solved. Firstly, the repair solution is described. Then, a safety check of the welded joint is presented. The final part refers to the techno-economic justification of the performed repair of the screw spindle. The obtained research results are important because the same problems or similar problems could appear in machine elements of various types of machine tools. Full article

Fault diagnosis is essential in industrial production. With the advancement of IoT technology, real-time data acquisition and storage have become feasible, enabling deep learning-based fault diagnosis methods to achieve remarkable results. However, existing approaches often overlook the temporal characteristics of fault occurrences and struggle with data imbalance between normal and faulty conditions, impacting diagnostic performance. To address these challenges, this paper proposes an integrated fault diagnosis method that incorporates data balancing, feature extraction, and temporal information analysis. The approach consists of two key components: (1) dataset construction using digital twin technology and (2) an integrated fault diagnosis model (CNN-BLSTM-attention). Digital twin technology generates virtual data under various operating conditions, mitigating the small-sample issue. The proposed model leverages a sliding window mechanism to capture both feature and temporal information, enhancing fault pattern recognition. Experimental results demonstrate that, compared to traditional methods, this approach effectively reduces noise interference and achieves a high diagnostic accuracy of 96.46%, validating its robustness in complex industrial settings. This research provides valuable theoretical and practical insights for improving fault diagnosis in industrial equipment such as screw presses. Full article

Total hip arthroplasty (THA) is a widely performed procedure to restore hip function in patients with degenerative joint diseases. Traditional “press-fit” fixation methods rely on sufficient bone quality for stability, but additional screw fixation is often necessary for patients with suboptimal bone conditions. However, comprehensive studies utilizing predictive modeling to optimize screw placement strategies in THA remain limited. This study integrates finite element analysis (FEA) with deep learning (DL) to optimize screw fixation strategies, enhancing implant stability and reducing revision rates. The design optimization process was conducted to refine key implant parameters before training the deep learning surrogate model. By utilizing advanced simulation techniques—including Goodness of Fit analysis, Response Graphs, Local Sensitivity Analysis, and Spider Charts—critical factors influencing stress distribution and fixation stability were identified. The optimization process ensured that the dataset used for deep learning training consisted of well-validated simulations, thereby improving the predictive accuracy of stress–strain responses. The findings indicate that optimized screw placement significantly improves load distribution, reducing stress concentrations and enhancing long-term implant stability. The comparative analysis of FEA and DL results showed that the DL-FEA surrogate model successfully replicated deformation patterns, though with a mean squared error (MSE) of 24.06%. While this suggests room for improvement, the model demonstrates potential for streamlining surgical planning. A comparative assessment with traditional methods highlights the advantages of DL-FEA in reducing computational time while maintaining precision. Future improvements will focus on refining the DL model, increasing the dataset size, and incorporating clinical validation. These findings contribute to developing a computational protocol for personalized acetabular cup fixation, with implications for reducing revision rates and improving surgical outcomes. Full article

The paper presents studies on the use of waste from wind turbine blades (WTBs) in the production of thermoplastic composites and regranulate-based products of acrylonitrile-butadiene-styrene (ABS) copolymers. Composites containing two types of WTB fractions (finely milled fraction—GRm and dust fraction—GRd) were produced using a co-rotating twin-screw extruder. During extrusion, different screw configurations of the plasticizing system as well as different material formulations were investigated. The studied composites contained from 10 to 70 wt% of shredded WTB, as well as up to 15 wt% of additional components, mainly those improving impact strength and processing properties. It was found that the individual WTB fractions generally deteriorate the mechanical properties of ABS. However, a composite containing 30 wt% GRm and modified with an additional 7 wt% ACM-G2 (impact modifier type) can be hot-pressed into good quality panels. It can also be successfully used to produce profiles in the extrusion process, mainly due to its significantly reduced viscosity. The studies presented in this article showed one of the possible ways of using WTB waste. It is advantageous because it uses WTB waste in a thermoplastic ABS matrix, which is also a secondary raw material. As a consequence of this, a completely new composite material based wholly on secondary raw materials can be obtained, which can be subjected to multiple processing. Full article

This study investigates the effects of hull and impurity content on the efficiency of cold-pressing high-oleic sunflower seeds using a screw press. High-oleic sunflower oil is valued for its oxidative stability and health benefits, and optimizing pressing conditions is crucial for maximizing yield and maintaining oil quality. The identification of high-oleic sunflower oil was performed by analyzing its fatty acid composition, iodine value, and refractive index. Eleven seed samples with varying hull and impurity contents were processed to assess their impact on cake composition, pressing efficiency, and pressing oil yield. Oil yield ranged from 39.24% to 76.52%, with higher hull content contributing to increased yield due to its role in facilitating oil drainage. Multiple linear regression models were developed to predict moisture and oil content in the cake, as well as pressing efficiency, based on hull and impurity content, demonstrating strong predictive accuracy. These parameters were selected as they represent economically significant indicators, given that moisture and oil content indirectly reflect the protein content in the cake, while sunflower cake is primarily used as animal feed. Additionally, pressing efficiency indicates oil yield during pressing, which is the most critical economic parameter of the cold-pressing process. Cluster analysis identified three sample groups with distinct characteristics, revealing interactions between seed composition and pressing performance. The results highlight the significance of seed preparation in optimizing cold-pressing efficiency and provide insights for improving oil extraction processes. These findings support the industrial application of high-oleic sunflower seed pressing and contribute to the development of sustainable, high-quality oil production methods. Full article

This study investigates the potential of Chirich (Asphodelus aestivus) tuber, one of Turkey’s natural resources, for sustainable bio-hybrid film production. Bio-hybrid films developed from Chirich tuber starch in composite form with polyvinyl alcohol (PVOH) were thoroughly examined for their physical, mechanical, and barrier properties. During the production process, twin-screw extrusion and hydraulic hot pressing methods were employed; the films’ optical, chemical, and barrier performances were analyzed through FT-IR spectroscopy, water vapor permeability, solubility, and mechanical tests. To evaluate the films’ durability against environmental factors and model their properties, advanced computational model algorithms such as Gradient Boosting Regression (GBR), Random Forest Regression (RFR), and AdaBoost Regression (ABR) were utilized. The results showed that the GBR algorithm achieved the highest accuracy with 99.92% R² and presented the most robust model in terms of sensitivity to environmental factors. The results indicate that Chirich tuber-based bio-hybrid films exhibit significantly enhanced mechanical strength and barrier performance compared to conventional corn starch-based biodegradable polymers. These superior properties make them particularly suitable for industrial applications such as food packaging and medical materials, where durability, moisture resistance, and gas barrier characteristics are critical. Moreover, their biodegradability and potential for integration into circular economy frameworks underscore their environmental sustainability, offering a viable alternative to petroleum-derived plastics. The incorporation of ML-driven optimization not only facilitates precise property prediction but also enhances the scalability of bio-hybrid film production. By introducing an innovative, data-driven approach to sustainable material design, this study contributes to the advancement of bio-based polymers in industrial applications, supporting global efforts to mitigate plastic waste and promote environmentally responsible manufacturing practices. Full article

The monitoring of grape maturity is essential for determining the ideal harvest time as well as for obtaining the expected characteristics of grape juice and, consequently, of wine. This study aimed to examine the impact of various laboratory-scale pressing methods on key chemical parameters (sugars, pH, and titratable acidity), as well as on phenolic-related indexes and antioxidant activity, in juices from Chardonnay (six grape samples) and Pinot blanc (two grape samples) across two vintages (2022 and 2023). The grape samples were characterized in terms of total and extractable flavonoids and extractability (%). Four different methods (manual pressing, vacuum pressing, small screw press, and juicer) were applied for producing grape juice. The results showed relevant differences in the extractability among the grape samples up to 64.1% and 43.8% for harvests 2022 and 2023, respectively. Comparable sugar content, pH, and titratable acidity were found in the juice samples independently from the method used. On the contrary, notable variability among the different pressing methods was revealed for phenolic-related indexes and antioxidant activity. The small screw press led to lower total phenol index values across grape batches compared to other methods, while the juice samples obtained with the juicer revealed a composition consistently differing in comparison to the other methods. Raman spectroscopy allowed to clearly classify the juice samples based on the pressing method. Good predictive models were obtained due to the composition of juice samples being clearly distinct among methods. This data suggests that an appropriate pressing method should be adopted for monitoring the grape ripening as well as for simulating the pressing under industrial scale. Full article

This study addresses the optimization of juice extraction from sea buckthorn (Hippophae rhamnoides) to meet the growing demand for healthy, natural food products. An upgraded screw press with a self-regulating pressure adjustment mechanism was developed and evaluated. Four spring types (wire diameters, 1–6 mm; maximum forces, 47.5–800 N) and screw rotation speeds ranging from 140 to 200 rpm were investigated for their effects on juice yield, compression density, internal pressure, and power consumption using sea buckthorn fruits. The results indicated that springs with higher maximum forces yielded greater juice outputs. The highest juice yield of 47% was achieved using a spring with a 3 mm wire diameter and 630 N maximum force (Spring 4) at 185 rpm. This configuration also demonstrated an optimal balance between compression density (948 kg/m³) and internal pressure (320 Pa) while maintaining the lowest power consumption (142 W). The internal pressure within the pressing chamber increased with both spring force and rotation speed. While Spring 2 generated the highest internal pressures (up to 570 Pa at 200 rpm), Spring 4 achieved moderate internal pressures, suggesting an effective pressure transmission. Spring 4 exhibited the lowest power consumption despite the high juice yields and compression densities. The study concludes that utilizing Spring 4 at 185 rpm optimizes the juice extraction efficiency while minimizing energy use. Equipment designs allowing the fine-tuning of pressure and rotation speed can significantly enhance the production efficiency in sea buckthorn juice extraction and potentially in other fruit-juice-processing applications. Full article

Nigella sativa L. (generally known as black cumin) is a medicinal plant prized for its therapeutic and nutritional benefits. Its seed oil is used extensively in pharmaceuticals, nutraceuticals, cosmetics, and cooking. However, extracting oil to satisfy the world’s needs leaves behind plenty of solid residues. The seeds of Nigella are loaded with health-benefiting phytoconstituents, but so might their extraction residues. While much research on seeds and oil has been carried out, there is relatively little information about solid residue, particularly regarding health-benefiting phytoconstituents. Additionally, there is a knowledge gap relating to how phytoconstituents transfer from seeds to solid residue during oil extraction and any loss of key phytoconstituents that may occur during this transfer. Understanding the health-benefiting phytoconstituents in Nigella solid residue is crucial for unlocking its full potential for value-added applications in health and nutrition. Moreover, understanding the dynamics of these phytoconstituent transfers is essential for optimizing extraction processes and preserving the nutritional and therapeutic value of the derived products. Therefore, this study investigated the composition of the screw-press solid residues of different Nigella genotypes grown under similar environmental conditions. The results showed moderate variation in the levels of potential health-benefitting phytoconstituents in Nigella solid residues regarding total phenolic content (TPC) (720.5–934.8 mg GAE/100 g), ferric reducing antioxidant capacity (FRAP) (853.1–1010.5 mg TE/100 g), cupric reducing antioxidant capacity (CUPRAC) (3863.1–4801.5 mg TE/100 g), thymoquinone (TQ) (156.0–260.1 mg/100 g), saturated fatty acid (SFA) (2.0–2.2 mg/g), monounsaturated fatty acid (MUFA) (2.0–3.6 mg/g), and polyunsaturated fatty acid (PUFA) (8.2–12.1 mg/g). Notably, TPC, FRAP, and CUPRAC had high transfer rates into the solid residue (78.1–85.9%, 65.4–75.7%, and 84.5–90.4%, respectively), whereas TQ, SFA, MUFA, and PUFA showed lower transfer rates (15.9–19.3%, 7.5–8.9%, 12.0–18.3%, and 6.5–7.5%, respectively). When summing the values of individual phytoconstituents transferred into oil and solid residue from their respective seeds during processing, it was found that only 80.6–88.3% of TPC, 74.2–84.4% of FRAP, 86.3–92.3% of CUPRAC, 54.4–64.9% of TQ, 68.5–92.4% of SFA, 76.2–90.6% of MUFA, and 51.6–76.6% of PUFA were transferred from the total value present in their respective seeds. Full article