Mechanical Pressing Research Articles

RESEARCH ON THE COMPRESSIVE BEHAVIOUR OF CERAMIC COMPOSITE MATERIAL BASED ON BENTONITE

The paper presents the results of a study on the compressive behaviour of ceramic composite made with bentonite matrix. During the study, samples were made of ceramic composite, of filter type, cylindrical with a diameter of 16 mm and heights between 14-16 mm. To achieve the porous structure, the matrix was reinforced with ceramic powders of Al2O3 and SiC, and to control the pore size, metal powders of Al and Fe were used in percentages between 3-12%. The compaction of the samples thus obtain was performed by mechanical pressing in a metal mould on a universal testing machine with a force F=20 kN. In order to test them in compression, the samples were sintered in an oven at T=1100°C in a heat treatment oven after a predetermined treatment cycle. For each test, the diagram was registered with the help of the software from the machine’s equipment, respectively the behaviour of the different sintered ceramic composite samples. The results thus obtained were analysed in correlation with the composition of the tested samples. In conclusion, dependencies were established between the type, nature and ratio of the constituent samples of ceramic composite and their behaviour at the request of compression.

Computer Simulation of Composite Materials Behavior under Pressing.

Composite materials have a wide range of functional properties, which is ensured by using various technological methods of obtaining both the matrix or fillers and the composition as a whole. A special place belongs to the composition formation technology, which ensures the necessary structure and properties of the composite. In this work, a computer simulation was carried out to identify the main dependencies of the behavior of composite materials in the process of the main technological operations of their production: pressing and subsequent sintering. A polymer matrix randomly reinforced with two types of fillers: spherical and short cylindrical inclusions, was used to construct the finite element models of the structure of composites. The ANSYS Workbench package was used as a calculation simulation platform. The true stress-strain curves for tension, Poisson's ratios, and ultimate stresses for composite materials were obtained using the finite element method based on the micromechanical approach at the first stage. These values were calculated based on the stretching diagrams of the matrix and fillers and the condition of the ideality of their joint operation. At the second stage, the processes of mechanical pressing of composite materials were modelled based on their elastic-plastic characteristics from the first stage. The result is an assessment of the accumulation of residual strains at the stage before sintering. The degree of increase in total strain capability of composite materials after sintering was shown.

Study of the influence of rubber on stremgth properties of carbon plastic

The use of elastomers allows us to purposefully change the structure of epoxy compositions, which largely determines the characteristics. Of particular interest are elastomers, such as silicone and polyurethane rubbers. In experimental works for the manufacture of carbon fiber plates, we used the method of manual molding with mechanical pressing. This technology is economical, does not require large labor costs, and less material consumption than when using other methods of formation. The effect of polyurethane and silicone rubbers as modifiers of increasing the impact strength of epoxy resin Etal-Inject-T hot curing has been studied. To determine the compressive strength of carbon fiber, the samples were tested on a universal test machine MUP200. The impact strength of carbon fiber was determined by the Charpy method. It is established that polyurethane and silicone rubbers have the same qualitative effect on the properties of epoxy resins. When modifying carbon fiber with polyurethane rubber with an increase in the content of up to 10%, the impact strength of carbon fiber increases to a maximum of 215 kJ/m2, with a significant increase in compressive strength up to 495 MPa. Optimal results were obtained with polyurethane rubber at 10% content of the substance. The main role of rubber in increasing the strength and elasticity of the material is that when the impact in a small amount of carbon fiber concentrates a lot of mechanical energy, the rubbers are stress concentrators, so the crack arises in the matrix adjacent to the elastomer (rubber). The increase in the toughness of the material can be associated with the formation of a dispersed phase of rubber, which loosens the structure of the cured epoxy resin.

Advances in seed oil extraction using ultrasound assisted technology: A comprehensive review

AbstractThe application of ultrasonic assisted extraction to extract seed oils for multifaceted food applications is discussed in this study. Seed oils, which are notable sources of health‐promoting characteristics and reservoirs of fatty acids and phytochemicals, are being targeted for effective extraction. Conventional techniques of oil extraction, including mechanical pressing and rendering, have limitations such as low extraction rate, high energy consumption, and low yield. In this context, ultrasonic assisted extraction is green and fast oil extraction technology with a greater extraction rate and low energy consumption. Ultrasound assisted oil extraction is mostly used technique since it is environmentally friendly and can be easily integrated with other extraction processes. Ultrasound‐aided extraction uses less solvent than traditional extraction methods. In this process, cavitation bubbles form in the solvent and burst, causing changes in pressure and temperature that expedite the mass transfer of solutes into solvent. The miscella, including the solvent and oil mixture, is then desolventized using evaporators, followed by steam‐stripping to remove the extracted oil. The current review paper discusses the characteristics of ultrasonic extractions for efficient oil extraction (extraction duration, ultrasound frequency, temperature, solvent employed, and ultrasound type). The conventional and non‐conventional oil extraction methods from sources have been examined in this article, in addition to the ultrasound assisted extraction. Along with traditional and advanced oil extraction techniques, the use of ultrasonication in conjunction with other cutting‐edge techniques is covered in this article.Practical applicationsUltrasound assisted oil extraction extracts oil from vegetables, oilseeds, and nuts by using a suitable carrier. The key parameters influencing ultrasound aided extraction of oilseed include particle shape and size, moisture content of seed, amount of solvent, and extraction time/temperature. The ultimate extraction yield is influenced by the extraction time, operating frequency, operational temperature, solvent type, and proportion, and ultrasonicator design. This technique consumes less energy and requires less maintenance. It is quite efficient and reliable. On this basis, ultrasound aided extraction may be utilized commercially to increase oil extraction rate from oil seeds.

3D Porous Compact 1D/2D Fe2 O3 /MXene Composite Aerogel Film Electrodes for All-Solid-State Supercapacitors.

2D MXene nanoflakes usually undergo serious restacking, that easily aggravates during the traditional vacuum-assisted filtration process; and thus, hinders the electrochemical performance of the corresponding film electrodes. Herein, 3D porous compact 1D/2D Fe2 O3 /MXene aerogel film electrode with an enhanced electrochemical performance is fabricated by freeze-drying assisted mechanical pressing. An introduction of 1D α-Fe2 O3 nanorods can not only alleviate the restacking of 2D MXene but also provide additional pseudocapacitance for the composite film system. Thus, the resulting Fe2 O3 /MXene aerogel film electrode shows an enhanced specific capacitance of 182 F g-1 (691 mF cm-2 ) at a current density of 1 A g-1 in 3 m H2 SO4 electrolyte as well as with 81.74% capacitance retention after 10000 charge-discharge cycles. Besides, the addition of 1D α-Fe2 O3 nanorods has a significant contribution in the volumetric capacitance of the composite aerogel film (150 F cm-3 ), which is 2.68 times that of the pure MXene aerogel film (56 F cm-3 ). Moreover, the fabricated all-solid-state symmetric supercapacitor (SSSC) delivers a superior areal energy density of 3.61 µWh cm-2 at a power density of 119.04 µW cm-2 . This rapid-forming 3D porous, binder-free, and freestanding aerogel film provides a progressive strategy for the fabrication of MXene-based electrode for supercapacitors.

Cold-Pressed Pomegranate Seed Oil: Study of Punicic Acid Properties by Coupling of GC/FID and FTIR.

Over the last decades, we have witnessed an increasing interest in food-related products containing vegetable oils. These oils can be obtained either by extraction or by mechanical pressing of different parts of plants (e.g., seeds, fruit, and drupels). Producers of nutraceuticals have ceaselessly searched for unique and effective natural ingredients. The enormous success of argan oil has been followed by discoveries of other interesting vegetable oils (e.g., pomegranate oil) containing several bioactives. This work describes the pomegranate fruit extract and seed oil as a rich source of conjugated linolenic acid as a metabolite of punicic acid (PA), deriving from the omega-5 family (ω-5). Through the chemical characterization of PA, its nutritional and therapeutic properties are highlighted together with the physiological properties that encourage its use in human nutrition. We analyzed the composition of all fatty acids with beneficial properties occurring in pomegranate seed oil using gas chromatography (GC) with flame-ionization detection (FID) analysis combined with Fourier transform infrared spectroscopy (FTIR). Pomegranate seed oil mainly consists of 9,11,13-octadic-trienoic acid (18:3), corresponding to 73 wt % of the total fatty acids. Nine components were identified by GC in PSO, varying between 0.58 and 73.19 wt %. Using midinfrared (MIR) spectroscopy, we compared the composition of pomegranate seed oil with that of meadowfoam seed oil (MSO), which is also becoming increasingly popular in the food industry due to its high content of long chain fatty acids (C20-22), providing increased oil stability. From the results of FTIR and MIR spectroscopy, we found that punicic acid is unique in PSO (73.19 wt %) but not in MSO.

Mathematical Modeling of Heat and Mass Transfer during Moisture–Heat Treatment of Castor Beans to Improve the Quality of Vegetable Oil

An important process in the technology of plant oil production by mechanical pressing is the wet–heat treatment of crushed oilseeds, in which the oilseed (compressed seed) is exposed to saturated vapor and a conductive heat supply. Optimal mode selection of wet–heat treatment based on a detailed study of the physical processes taking place in the compressed seed increases oil release, improves its quality indicators, and decreases energy consumption. Mathematical modeling is an advanced method for studying the dynamics of humidification and frying in the compressed seed. The article introduces a mathematical model and a numerical method for calculating heat-and-mass transformation and phase conversion in the process of the humidification and frying of compressed seeds of the castor plant in a continuous multi-stage heating kettle. This study provides equations for calculating the intensity of phase transformation on the inner and outer surfaces of the wet layer. Data verification indicates the adequacy of the mathematical model, effectiveness of the numerical method, and possibility of their use in optimizing the modes of wet–heat treatment for compressed seed raw material.

EXTRACTION, CHARACTERIZATION AND APPLICATIONS OF CASTOR SEED OIL FROM WILD Ricinus communis

The extraction of Castor oil was accomplished by mechanical cold pressing of the seeds of wild castor plant (Ricinus communis) found in Ini Local Government, Area Akwa Ibom State, Nigeria. Oil yield was 38.69%. The virgin oil (obtained as clear, viscous, pale-yellow liquid) was further purified by filtration through sintered glass (fine mesh screen). This was to eliminate any dust, gum, or other particulates present. Physicochemical characterization of the purified oil revealed low acid value (2.07), low iodine value (84.18), low peroxide value (38.00), but relatively high specific gravity (0.959), hydroxyl (163.64) and saponification (175.31) values. These values compare favourably with ASTM standards and general specifications for industrial grade castor oil (WHC, 2012), suggesting that the oil has good industrial potential. Fourier transform infra-red (FTIR) spectroscopic analysis has confirmed the presence of major functional groups in the oil, notably hydroxyl l (3414.12cm-1), carbonyl (1739.85cm-1), olefinic (1659.80cm- ) and methylenic (2925.15cm-1 ). Determined fatty acid composition of the oil by gas chromatography-mass spectrometry (GC-MS) shows ricinoleic acid (74.10%) as the major constituent fatty acid. Other fatty acids were linoleic (10.32%), oleic (7.55%), stearic (2.81%), palmitic (2.59%), erucic (1.70%) and eicosadienoic (0.93%). The appreciable oil yield (39.43%) from this castor seed variety, the quality, unique physicochemical characteristics of the extracted oil, and the renewable nature of castor oil as a natural resource justify the oil’s commercialization and full exploitation in traditional, as well as novel areas (e.g. biopolymer and biofuel production) of industrial application.

Powders Based on Ca2P2O7-CaCO3-H2O System as Model Objects for the Development of Bioceramics

Nanoscale powders of hydrated Ca2P2O7, CaCO3, and a product of mixed-anionic composition containing P2O74− and CO32− anions were synthesized from aqueous solutions of Ca(CH3COO)2, pyrophosphoric acid (H4P2O7), and/or (NH4)2CO3. Pyrophosphoric acid was previously obtained on the basis of the ion exchange process from Na4P2O7 solution and H+-cationite resin for further introduction into the reactions as an anionic precursor. The phase composition of powders after the syntheses was represented by bioresorbable phases of X-ray amorphous hydrated Ca2P2O7 phase, calcite and vaterite polymorphs of CaCO3. Based on synthesized powders, simple cylindrical constructions were prepared via mechanical pressing and fired in the temperature range of 600–800 °C. Surface morphology observation showed the presence of bimodal porosity with pore sizes up to 200 nm and 2 μm, which is likely to ensure tight particle packing and roughness of the sample surface required for the differentiation of osteogenic cells. Thus, the prepared ceramic samples can be further examined as model objects for bone tissue repair.

Porphyrin COF and its mechanical pressing-prepared carbon fiber hybrid membrane for ratiometric detection, removal and enrichment of Cd2+

A nitrogen (N), oxygen (O)-rich porphyrin-based covalent organic framework (COF), in which interlayer porphyrin molecules are vertically stacked, is prepared and characterized. As-prepared N,O-rich TpTph COF shows a high adsorption capacity for Cd2+ due to the abundant coordination sites. More interesting, it is found that the formation of COF enlarges the porphyrin ring center space, thus facilitating the Cd2+coordination, and the resulting optical signal changes make the ratiometric detection of Cd2+ possible. Furthermore, using carbon fiber (CF) filaments, which are obtained from low cost and easy-to-obtain actived carbon mask, as support, porphyrin COF-based CF@TpTph membrane is prepared through in-situ growth of COF on the support followed by simple mechanical pressing. The CF@TpTph membrane is demonstrated to work well for both Cd2+ removal and enrichment from soil and water samples, and shows the advantages of ease of handling, robust stability, reduced secondary pollution risk to samples, and good reusability. This work provides a powerful tool for Cd2+ removal and enrichment, exhibits that preparing porphyrin-based COFs is a feasible way to promote the interactions between porphyrin ring and Cd2+, and demonstrates that mechanical pressing is a promising strategy for the design of COF-based monolithic materials to promote the practical applications of COFs.

Mechanically hot-pressed flattened plastic optical fiber-based SPR sensor and its RI sensing

This paper presents a surface plasmon resonance (SPR) sensor based on a flattened plastic optical fiber (POF) for refractive index (RI) sensing. The flattened POF is fabricated by mechanical hot pressing. Afterwards, a thin film of Ag and Au is first deposited on one side of the flat surface to excite the SPR effect. The results show that the flattened POF-based SPR probe coated with the Au film has a sharper SPR peak and a narrower peak width than the probe coated with Ag film. To improve the SPR effect, two flat surfaces of the flattened POF are coated with metal film (Ag and Au). It was found that the sensor showed better RI sensing performance compared to the sensor with only one flat surface coated with metal film. For the flattened POF with two flat surfaces coated with Ag film, achieving the highest RI sensitivity of 2507 nm/RIU in the RI range of 1.33–1.39. The proposed sensor is a low-cost solution for RI measurement with potential applications in the medical and biochemical fields.

Enzymatic aqueous extraction with ultrasound: a prospective overview on the state of the art

The oil extracted from different oleaginous raw materials is usually obtained through mechanical pressing, associated or not with organic solvents. The objective of this prospection was to evaluate if the aqueous enzymatic extraction (AEE) with ultrasound should be a cleaner and more effective technology for the production of lipids and other products. The state of the art of this issue was observed with a focus on food, and more precisely oleaginous fruits and seeds. The advanced search in the Science Direct, Scopus and Web of Science (WOS) databases was carried out in July 2021. A total of 1,099, 79, and 46 scientific papers were retrieved within the Science Direct, WOS and Scopus databases, respectively. Identifying the experiments made in these studies with EAE and ultrasound, there was a selection of 24, 13 and 4 original articles in the investigated bases. The articles described that ultrasound used as pre-treatment or during AEE increased the yield of food lipid extraction. This prospection described that EAE technology and ultrasound are impactful techniques in obtaining lipids. The advanced research highlighted that there is a gap related to researches with oleaginous matrices and the replacement of conventional techniques with clean techniques can be economically feasible.

Leveraging Bioprocessing Strategies to Achieve the Simultaneous Extraction of Full-Fat Chickpea Flour Macronutrients and Enhance Protein and Carbohydrate Functionality

The concurrent extraction of lipids, proteins, and carbohydrates can be achieved by aqueous and enzymatic extraction processes, circumventing the low extractability by mechanical pressing and the use of flammable solvents. The use of alkaline protease, preceded or not by carbohydrase pretreatments, was evaluated on the extractability of oil, protein, and carbohydrates from full-fat chickpea flour and protein functionality. Enzymatic extraction increased oil and protein extractability from 49.8 to 72.0–77.1% and 62.8 to 83.5–86.1%, respectively. Although the carbohydrase pretreatments before the addition of protease did not increase oil and protein extractability, the carbohydrate content of the extracts increased from 7.68 to 9.17−9.33 mg/mL, accompanied by the release of new oligosaccharides in the extracts, as revealed by LC–MS/MS characterization. Enzymatic extraction yielded proteins with significantly higher solubility (25.6 vs. 68.2–73.6%) and digestibility (83.8 vs. 90.79–94.67%). Treatment of the extracts with α-galactosidase completely removed the flatulence-causing oligosaccharides (stachyose and raffinose). This study highlights the effectiveness of environmentally friendly bioprocessing strategies to maximize lipid, protein, and oligosaccharide extractability from full-fat chickpea flour with concurrent improvements in protein solubility and in vitro digestibility, reduction of flatulence related oligosaccharides, and generation of a more diverse pool of oligosaccharides for subsequent prebiotic evaluation.Graphical abstract

Scaling up the Two-Stage Countercurrent Extraction of Oil and Protein from Green Coffee Beans: Impact of Proteolysis on Extractability, Protein Functionality, and Oil Recovery

Green coffee processing has been hindered by low oil extraction yields from mechanical pressing and the need of using flammable and hazardous solvents for defatting the protein-rich cake before subsequent protein extraction. To replace the use of flammable solvents and enable the simultaneous extraction of lipids and proteins from green coffee beans at reduced water usage, a multistage countercurrent extraction process was scaled up from 0.05 to 1.14 kg and evaluated regarding protein and oil extractability, physicochemical and functional properties of the extracted protein, and oil recovery. Enzymatic extraction increased protein extractability by ~13% while achieving similar oil extractability when not using enzymes (55%). Proteolysis resulted in the release of smaller proteins with reduced surface hydrophobicity and higher solubility at acidic pH (3.0–5.0). The physicochemical changes observed due to proteolysis resulted in the formation of emulsions with reduced resistance against enzymatic and chemical demulsification strategies, enhancing the recovery of the extracted oil (48.6–51.0%). Proteolysis did not alter the high in vitro digestibility of green coffee proteins (up to 99%) or their emulsifying properties at most pH values evaluated. However, proteolysis did reduce the foaming properties of the hydrolysates compared with larger molecular weight proteins. These findings revealed the impact of extraction conditions on the extractability and structural modifications altering the functionality of green coffee proteins and the synergistic impact of extraction and demulsification strategies on the recovery of the extracted oil, paving the way for the development of structure–function processes to effectively produce green coffee proteins with desired functionality.

Roasting treatments affect physicochemical, aroma and nutritional quality of strong fragrant rapeseed oil

The strong fragrant rapeseed oil (SFRO) attracts the growing interest in China due to its fragrant flavor, attractive color, and physical and oxidative stability. It is usually produced with simple processes including rapeseed roasting, mechanical pressing, and degumming with hot water (80–90 °C). To produce SFROs with high quality and nutritional contents, the seed roasting parameters including temperature up to 220 °C and time ranging from 10 min to 30 min were investigated. Results showed that 20-min roasting at temperature 160 °C resulted in the highest oil extraction yield of 33.20% with the lowest water content of 0.121%. The produced SFRO had the roasted, nutty and soft tastes with the maximum overall score, the highest total tocopherol and sterol contents of 789.73 mg/kg and 4582.80 mg/kg, respectively, and high CoQ10 content of 65.57 mg/kg. Over-roasting at roasting temperature of over 180 °C and time of over 30 min led to the high Lovibond red readings, off-flavors, and increased concentrations of high saturated fatty acids and Benzo[a]pyrene (BaP). Our findings would provide a reference to produce SFROs with the highest extraction yield and nutrient contents, acceptable physicochemical properties, optimal profile of the fatty acids and the key aroma compounds, and relatively-low BaP concentration.

Combining pressing and alkaline extraction to increase protein yield from Ulva fenestrata biomass

Many seaweed species have a high production potential and attract interest as future protein sources. A high fiber and ash content, however, demand extraction of the protein to improve its digestibility and protein utilization in food or feed. This study explores three different approaches for protein extraction from Ulva fenestrata in order to maximize the protein extraction yield. Soluble protein was recovered either by mechanical pressing or by homogenization and osmotic shock of the biomass followed by alkaline extraction. The soluble protein was then concentrated by isoelectric precipitation. A combined procedure was carried out by pressing the biomass and following subjecting the residual pulp fraction to homogenization, osmotic shock and alkaline extraction. The three methods were ranked as follows with respect to protein extraction yield (as % of biomass protein); the combined method (23.9 ± 0.3%)> the alkaline extraction (6.8 ± 0.2%)> mechanical pressing (5.0 ± 0.2%). The significant increase when combining the methods was ascribed to a high precipitation yield after alkaline extraction of the pulp, hypothesized to be due to a reduced conductivity of the alkali-soluble protein fraction when derived from pulp rather than whole biomass.

Effects of acidified blanching water and pectinase enzyme pretreatments on physicochemical properties and antioxidant capacity of Carica papaya juice.

The high pectin content in papaya (Carica papaya) causes the juice extraction to be difficult and results in a low yield. This study aims to determine the effect of acidified blanching water and pectinase enzyme pretreatments on the yield, physicochemical properties, and antioxidant activities of the papaya juice. For acidified blanching treatment, papaya cubes (3 cm3 ) were blanched in water containing 0%, 0.5%, 1.5%, and 2.5% w/v citric acid at 95℃ for 2 min. For enzyme treatment, a pectinase enzyme (10, 20, and 30ppm) was added to the homogenous papaya puree and incubated at 45℃ (200rpm) for 60 min. The enzyme reaction was stopped by pasteurization at 74℃ for 2 min. The puree was filtered, and the juice was pasteurized at 74℃ for 7 min. All pretreated papaya juice were analyzed for physicochemical properties (color, clarity, viscosity, pH, total soluble solids [TSSs], total carotenoid content, total phenolic content [TPC], and total flavonoid content [TFC]), and antioxidant activities (2,2-diphenyl-1-picrylhydrazyl [DPPH] and ferric reducing antioxidant power [FRAP] assay). Both pretreatments improved the clarity of papaya juice, and was significantly greater after pretreatment with pectinase enzyme. The TPC and antioxidant activities of papaya juice were conserved and maintained by acidified blanching at 1.5% (w/v) citric acid. Increased concentrations of pectinase enzyme significantly reduced the TPC and total carotenoid content. Pretreatment with pectinase enzyme up to 20ppm does not significantly reduce the TFC and antioxidant activities. Acidified blanching and pectinase enzyme pretreatments have an impact on extraction of papaya fruit juice while retaining the nutritional composition of the juice. PRACTICAL APPLICATION: Papaya (Carica papaya) is a fruit with great nutritional values but is highly perishable and prone to postharvest loss. Juice has become a more cost-effective and convenient option for preserving the fruit. However, since papaya is a pectin-rich fruit, the extraction of juice using mechanical pressing is difficult due to the bonding of juice to the pulp in the form of a jellied mass, which results in juice with low yield. Using acidified blanching and pectinase enzyme to clarify the juice not only increases the yield but also retains the nutrient composition of the juice.

Fabrication and Characterization of the Porous Ti4O7 Reactive Electrochemical Membrane.

Preparation of the Magnéli Ti4O7 reactive electrochemical membrane (REM) with high purity is of great significance for its application in electrochemical advanced oxidation processes (EAOPs) for wastewater treatment. In this study, the Ti4O7 REM with high purity was synthesized by mechanical pressing of TiO2 powders followed by thermal reduction to Ti4O7 using the Ti powder as the reducing reagent, where the TiO2 monolith and Ti powder were separated from each other with the distance of about 5 cm in the vacuum furnace. When the temperature was elevated to 1333 K, the Magnéli phase Ti4O7 REM with the Ti4O7 content of 98.5% was obtained after thermal reduction for 4 h. Noticeably, the surface and interior of the obtained REM bulk sample has a homogeneous Ti4O7 content. Doping carbon black (0wt%-15wt%) could increase the porosity of the Ti4O7 REM (38–59%). Accordingly, the internal resistance of the electrode and electrolyte and the charge-transfer impedance increased slightly with the increasing carbon black content. The optimum electroactive surface area (1.1 m2) was obtained at a carbon black content of 5wt%, which increased by 1.3-fold in comparison with that without carbon black. The as-prepared Ti4O7 REMs show high oxygen evolution potential, approximately 2.7 V/SHE, indicating their appreciable electrocatalytic activity toward the production of •OH.

Simultaneous integration of supercritical fluid extraction and mechanical cold pressing for the extraction from Baru seed

Supercritical fluid extraction (SFE) assisted by cold pressing (SFEAP) was previously reported in the literature for oleaginous raw materials to improve the SFE process, but it suffers from operational disadvantages due to its sequential, instead of simultaneous, extraction operations. Therefore, this study aimed to address this issue by simultaneous integrating of SFE and mechanical cold pressing. This new extraction unit, which is called sCO2 + MCP, was successfully examined for the extraction of oil from Baru seed (BS) under the extraction pressure from 10 to 30 MPa and piston pressure from 10 to 30 MPa. The highest extraction yield (25.1% w/w) obtained by a combination of piston pressure of 15 MPa and an extraction pressure of 10 MPa. The main advantage of the sCO2 + MCP unit over SFE and SFEAP units is significantly reducing extraction pressure from 35 MPa to 10 MPa.

Identifying critical parameters for extraction of carnosine and anserine from chicken meat with high voltage pulsed electric fields and water

Carnosine (β-alanyl-L-histidine) and its methylated counterpart anserine (β-alanyl-1-methylhistidine) are important functional dipeptides found in various vertebrates' tissues. In this study, we identified the critical parameters of pulsed electric fields (PEF), coupled to mechanical pressing, followed by incubation in water up to 240 min for the extraction of these bioactive dipeptides from chicken meat. We show that PEF improves the kinetics of anserine and carnosine release to water by 7 to 53%, compared to the same water extraction process without PEF when the incubation time is below 120 min. A fractional factorial design showed that the incubation time in the water, after PEF pretreatment, had the most significant effect on dipeptides extraction. The maximum achieved total protein yield was 15.5 mg gfresh weight(FW)-1 after 120 min incubation in water. The maximum carnosine extraction yield was 7.48 mg gFW−1 with a maximum anserine extraction yield of 3.05 mg gFW−1. The specific energy yield of extraction of protein, carnosine, and anserine was 488.16 mg J−1, 39.43 mg J−1, and 131.63 mg J−1 respectively. The developed method is scalable and could be further explored to extract bioactive compounds from animal tissues.