High Voltage Electrostatic Field Research Articles

Transcriptomic responses of ‘Huping jujube’ (Zizyphus jujuba mill. cv. Huping) fruit to combined treatment of acidic electrolyzed water and high-voltage electrostatic field

The molecular mechanism underlying the preserving superior quality attributes of postharvest Huping jujube fruit by combining acidic electrolyzed water and high-voltage electrostatic field (AH) treatment remained unclear. The high-throughput sequencing analysis revealed a total of 3590 common differentially expressed genes (DEGs) in the T-W-CK0 vs T-W-CK75 and T-W-CK75 vs T-W-AH75 groups. AH treatment down-regulated most genes associated with respiratory metabolism, as well as lignin and anthocyanin biosynthesis, thereby maintaining lower physiological activities, improving taste and color quality of mature-white jujube. Additionally, AH treatment downregulated the genes involved in reactive oxygen species (ROS) generation and disease resistance, while simultaneously upregulating the genes associated with ROS elimination. This suggested that AH treatment could inhibit pathogen infection to prevent the activation of plants’ active defense and reduce the ROS-induced damage. In sum, the present study provided a comprehension explanation that AH treatment improved the storage quality attributes of jujube fruit at the genetic level.

High-voltage electrostatic field with 35 kV-15 min could reduce Pseudomonas spp. to maintain the quality of pork during −1 °C storage

This study evaluated the bacterial-reducing effects of different high voltage electrostatic field (HVEF) parameters (voltage 20,25,30,35 kV, time 5,10,15,20 min) on chilled pork, and studied the effects of HVEF bacterial-reducing treatment on the microbial number and the quality of pork during ice-temperature (−1 °C) storage. The results showed that HVEF of 35 kV-15 min was the best parameter, which made a 0.51 log CFU/g bacterial reduction. HVEF treatment reduced the number of Pseudomonas spp. by 0.50 log CFU/g, but no significant decrease was found in Brochothrix thermosphacta and lactobacilli. The abundance of Pseudomonas fragi (most abundant species in pork) significantly decreased after HVEF treatment, which may be the reason for the significant decrease of TVB-N and TBARS in HVEF group at the end of storage. During −1 °C storage, HVEF group exhibited better quality characteristics on shear force and cooking loss, which could effectively extend the shelf-life of chilled pork. Industrial relevanceHigh voltage electrostatic field (HVEF) is an emerging non-thermal inactivation technology. However, it is necessary to optimize the processing parameters based on the characteristics of the food. This study optimized the optimal processing parameters of HVEF for chilled pork and validated its contribution to maintaining the quality of pork during ice-temperature storage. These findings are of great significance for food processing, food preservation and the development of new refrigeration equipment.

Effect of high-voltage electrostatic field treatments on bananas (Musa paradisiaca var. sapientum) on their postharvest quality, enzymatic activity and morphological changes

In this work, the effects of high-voltage electrostatic field (HVEF) on enzyme activities and appearance of stored Musa sapientum were investigated as well as the intensity of spotting by Digital Image Analysis (DIA). By applying HVEF at 6 kV cm−1 during 7.5 minutes, color features on their surface after day 4, maintained stable values (R ≥ 191, G ≥ 165, L* ≥ 82, and b* ≥ 41), while control samples had lower figures of these parameters. Enzyme activities (expressed as Umg protein−1), for pectinmethylesterase in peel, HVEF treatments induced values ≤ 9 Umg−1, while control ≥ 16 Umg−1; polygalacturonase in peel; HVEF samples had activities ≤ 120 Umg−1 at days 6 and 8, while control samples ≥ 211 Umg−1; and, in pulp, after day 4, HVEF brought activities ≤ 37 Umg−1 while control samples were ≥ 71 Umg−1. Polyphenoloxidase, activities for treated samples were enhanced (in the peel, HVEF samples ≥553 Umg −1 and control ones ≤425 Umg−1; and for pulp, HVEF induced activities ≥979 Umg−1 while control ≤717 Umg −1). These results did not impact negatively in the spotting on the surface of the fruits. Results suggested that HVEF can extend the shelf life of M. sapientum.

Health Benefits of High Voltage Electrostatic Field Processing of Fruits and Vegetables.

High voltage electrostatic field processing (HVEF) is a food preservation procedure frequently used to produce healthy minimally processed fruits and vegetables (F&V) as it reduces the growth of microorganisms and activates or inhibits various enzymes, thus retarding their natural ripening while preserving and even enhancing native nutritional quality and sensory characteristics. HVEF is one of the various nonthermal processing technology (NTPT) regarded as abiotic stress that can activate the antioxidant system of F&V and can also inhibith spoilage enzymes as, polyphenol oxidase (PPO), lipoxygenase (LOX), pectin methylesterase (PME), polygalacturonase (PG), cellulase (Cel), β-xylosidase, xyloglucan and endotransglycosylase/hydrolase, bringing positive effect on hardness, firmness, colour attributes, electric conductivity, antioxidant compounds, microstructure and decreasing electrolyte leakage (EL), malondialdehyde (MDA) contents and browning degree. This technique can also increase the contents of fructose, glucose, and sucrose and decrease the production of CO2 and H2O2. Additionally, it has been reported that HVEF could be used with other treatments, such as modified atmosphere packaging (MAP) and acidic electrolyzed water (AEW) treatment, to enhance its effects. Future works should deepen on elucidating the activation of the antioxidant systems by applying HVEF of critical enzymes related to the synthesis pathways of phenolic compounds (PC) and carotenoids (Car). Holistic approaches to the effects of HVEF on metabolism based on systems biology also need to be studied by considering the overall biochemical, physical, and process engineering related aspects of this technique.

A new strategy to improve the quality of frozen chicken wings: High voltage electrostatic field combined with phosphorus-free water retaining agent

Freezing is a commonly used method for long-term storage of chicken wing products, of which disadvantages are mainly the product damage caused in the process. The aim of this study was to improve the freezing quality of chicken wings with a combination of phosphorus-free water retaining agent (WRA) and high-voltage electrostatic field (HVEF). The effect of WRA acting at different HVEF intensities (0, 1, 3, and 5 kV/cm) on the quality attributes of frozen chicken wings was investigated in 0, 7, 14, 21, 28 and 35 days of frozen storage. The results showed that WRA had functional properties of significantly improving the water holding capacity (WHC), color and texture properties, and fat stability of frozen chicken wing samples. The application of HVEF on this basis helped to promote the absorption of WRA and inhibit oxidative deterioration of chicken wing samples during frozen storage. Meanwhile, the combination of HVEF at 3 kV/cm was more prominent in terms of improvement in WHC, moisture content, color, protein secondary structure and microstructure integrity. This advantage had been consistently maintained with the extension of storage time. Overall, WRA combined with HVEF of 3 kV/cm can be used as an effective strategy to improve the freezing quality of chicken wing samples and has the potential to maintain the frozen chicken wing samples quality for a long time.

High voltage electrostatic field and composite coating impact on the quality of Sichuan pepper

The effects of coated film (CF), high voltage electrostatic field (HVEF), and high voltage electrostatic field combined with coated film (HVEFCF) treatment on the quality of Sichuan pepper during storage at room temperature (temperature: 25 ± 2 °C, humidity: 20 ± 2%) were investigated. The pectin (1%), sodium carboxymethyl cellulose (0.5%), and ascorbic acid (0.04%) were used to prepare the CF solution. The influence of different treatments on the colour, antioxidant activity, flavor components, OH-α-sanshool content, total phenolic content (TPC), and total flavonoid content (TFC) of Sichuan pepper during storage was evaluated. The results showed that HVEFCF treatment significantly reduced the colour change and loss of antioxidant activity of Sichuan pepper during storage. Meanwhile, HVEFCF-treated Sichuan pepper reduced the loss of flavor compounds during storage. Moreover, HVEF-treated Sichuan pepper reduced the loss of TPC and TFC by 106.16% and 44.02%, respectively, after 60 days of storage compared with the control check (CK) group. Furthermore, after 60 days of storage, the amount of OH-α-sanshool in the Sichuan pepper treated with HVEFCF was 9.72 mg/g, significantly preserving the loss of numbing compounds as compared to the CK group. To summarise, HVEFCF is a simple, cheap and efficient way to reduce the quality loss of Sichuan pepper during storage, which has a wide range of application scope in the future.

Mitigating quality deterioration in chilled pork by combining cinnamaldehyde nanoemulsions and a high-voltage electrostatic field

Cinnamaldehyde nanoemulsion (CNE) was obtained through ultrasonication, using Tween 80 as an emulsifier. The CNE was then applied to chilled pork in conjunction with a high-voltage electrostatic field (HVEF) to mitigate quality deterioration during refrigerated storage. The particle size of CNE ranged from 60 to 150 nm and was positively correlated with the amount of added cinnamaldehyde. The polydispersity index and zeta potential of CNE ranged from 0.25 to 0.30 and − 12 to −11 mV, respectively, indicating a narrow size distribution and stability. The CNE released the odor specific to cinnamaldehyde to pork in the first 4 days of chilling; however, it had little effect on the taste. HVEF pretreatment reduced the initial total viable count (TVC) in pork by 1.14 log cycle. The combination of CNE with HVEF successfully slowed down the loss of moisture, decrease in pH, and accumulation of total volatile basic nitrogen in pork during refrigeration. Furthermore, it mitigated the increase in TVC of pork. Therefore, this integrated method appears to be suitable for extending the shelf life of chilled pork.

Synergistic pre-deodorization effect of lysozyme and yeast extracts with high-voltage electrostatic field on crab meatballs

The undesirable odor of crab meatballs was evident after boiling and cooling, high-voltage electrostatic field (HVEF), lysozyme and yeast extract (LY), and the combination (LYH) were all applied to pre-deodorize crab meatballs to estimate the effect in view of odor, pH, fat oxidation and protein oxidation. None of the tert-butylamine (1.58 ± 0.14 ng/g), (E, E)-2,4-Dodecadienal (18.52 ± 0.12 ng/g), 1-Octen-3-ol (13.51 ± 0.22 ng/g) and nonanal (681.55 ± 0.24 ng/g) in the control were detected in LYH group, while nonanal in HVEF and LY groups was reduced by 86.07% and 42.60%, respectively. Thirteen volatile substances with variable importance plot ≥1 contributed prominently to the odor of crab meatballs depended on partial least squares discrimination analysis. Protein oxidation of the pretreated crab meatballs was alleviated, as well as thiobarbituric acid reactive substances (TBARS) and lipoxygenase (LOX) activity, with the best inhibitory effect of LYH being 40.10% and 62.80% on the respective effects. The correlation analysis derived that fishy substances were significantly positively correlated with TBARS and pH. LYH was the optimal pre-deodorization, which involved promoting glycolysis and lactic acid bacteria colonization in the liquid medium, and inhibiting fat oxidation by affecting enzyme activity in HVEF.

The synergistic antimicrobial effects and mechanism of cinnamon essential oil and high voltage electrostatic field and their application in minced pork

Spice essential oils (EOs) have potent antimicrobial ability, but their application as food preservatives was severely limited by strong sensory properties. In this study, high voltage electrostatic field (HVEF) was applied to strengthen the antimicrobial effect of EOs while reducing their additive dosage. First, cinnamon essential oil (CEO) was selected from ten spice EOs because of its strongest inhibition against bacteria (Escherichia coli and Staphylococcus aureus) and molds (Penicillium citrinum and Aspergillus niger) common in foods. Then, the antimicrobial effect and mechanism of CEO and HVEF used alone or in combination were investigated. The results exhibited that the antimicrobial effect of CEO was dramatically enhanced by combining with HVEF, as the required concentration for the same antimicrobial effect was only 1/4∼1/3 of that when used alone. Both CEO and HVEF treatments changed the permeability of the microbial cell wall as well as the permeability and integrity of the cell membrane, resulted in the change in membrane protein structure, led to the increase in content of reactive oxygen species in the microbial cells, while the combined treatment of HVEF and CEO (HVEF + CEO) caused the significantly greater effect on microbes than two treatments applied alone. Finally, HVEF was found to substantially improve the preservative effect of CEO, allowing CEO to prolong the shelf life of minced pork from about 3 d to 7 d without compromising its original sensory quality.

Effects of high voltage electrostatic field assisted freezing enhanced with ultrahigh permittivity ceramic on quality attributes of grass carp (Ctenopharyngodon idella) fillets during frozen storage

Small sample capacity is a critical limitation for the industrialization of the high voltage electrostatic field assisted freezing (HVEFF) technique. In this study, using grass carp as a sample, the effects of ultrahigh permittivity ceramic enhanced HVEFF system on the quality attributes of grass carp (Ctenopharyngodon idella) fillets during freezing and frozen storage were investigated. The appropriate electrostatic field strength for freezing grass carp fillets was determined first with the HVEFF Peltier cooling platform and then used for the freezing and frozen storage of grass carp fillets in an HVEFF refrigerator at −18 °C. The biochemical qualities, and ice crystal morphology of the samples were measured every 2, 4, 6, and 8 weeks during frozen storage. Compared to the frozen control, this novel HVEFF system could effectively delay the deterioration of texture and water migration, and reduce TVB-N, TBARS and the equivalent ice crystal diameters. This study not only showed the positive effect of this novel HVEEF system on the frozen preservation of grass carp fillets but more importantly provided a solution to the bottleneck of HVEFF industrialization.

The impact of high voltage electrostatic field on the storage quality and metabolism of Chinese kale

The impact of high voltage electrostatic field on the storage quality and metabolism of Chinese kale

Optimization of Parameters for Fluidized Bed-Type Tribo-Electrostatic Separation of End-of-Life Vehicle Waste Polymer Particles by Response Surface Methodology

End-of-life vehicles (ELVs) have resulted in huge quantities of waste vehicle polymers, the reuse of which could be effective in mitigating pollution and creating economic value. Based on the developed fluidized bed-type electrostatic separation equipment, this paper investigated the separation of two groups of commonly used mixed vehicle-use polymer particles, namely, acrylonitrile-butadiene-styrene (ABS)-polyamide (PA)-polypropylene (PP) (black) and polyethylene (PE)-PP (white)-polyvinyl chloride (PVC). First, the force of the particle in an electric field was analyzed, and the kinetic model of the particle in a high-voltage electrostatic field was established. Then, individual factor experiments were conducted on the fluidization time (T), the first-stage electrostatic separation chamber electrode voltage (U 1), the second-stage electrostatic separation chamber right field electrode voltage (U 3) and the second-stage electrostatic separation chamber left field electrode voltage (U 5) to investigate the pattern of separation results affected by each of these factors, individually. Finally, based on response surface methodology (RSM) experiments, the effects of the abovementioned three factors and their interactions on the purity of the separation of the three types of particles in each group were analyzed. The optimum separation parameters for ABS-PA-PP (black) particles in the experiments were determined as follows: T of 385 s, U 1(U 3) of −32 kV and U 5 of −37 kV. The optimum separation parameters for PE-PP (white)-PVC particles were found as follows: T of 398 s, U 1(U 3) of −40 kV and U 5 of −38 kV. The experimental validation of the abovementioned parameters obtained the purities of the three set of ABS-PA-PP (black) types of particles being 95.67%, 91.34% and 99.12%, respectively. The purities of the three set of PE-PP (white)-PVC types of particles being 96.21%, 93.20% and 86.74%.

Synthesis and properties of biomass derived carbon/PEG composite as photothermal conversion effective phase change material for functional concrete

Mixing phase change material (PCM) into concrete is a practical strategy for functionalizing concrete as an energy-storage unit. This study aims to invent an efficient photo-thermal conversion type PCM for the manufacturing energy storage functional concrete, which meet the needs of hydration heat storage and thermal storage in service. To solve the liquid leakage problem of PCM, a novel bamboo-based hydrothermal carbon sphere (HCS) with unique mesoporous structure was prepared to pack polyethylene glycol (PEG) to make shape stable PCM. The photo-thermal material nano-Ag was successfully introduced into the composite PCM through a high-voltage electrostatic field. To understand the stability and performance of the PCM for concrete use, the structural composition and thermal storage efficiency of Ag@HCS-CNTs/PEG in simulated concrete pore solution (a highly alkaline solution containing potassium, sodium, and calcium cations) were systematically studied via multiple characterization methods. After being soaked in concrete pore solution for 7 days, the PCM shows outstanding thermal storage density (147 J/g), photo-thermal conversion efficiency (110.6%), and resistance to Na+, Mg2+, Cl− and SO42−. In addition, the biomass subtracted PCM preparation has low energy consumption and low carbon emission features. These open a window of realistic PCM application in the structural concrete, insulation porous walls and energy storage buildings.

Enhanced pool boiling performance of cellular metal foams by electrostatic fields for high-power thermal management

Pool boiling of cellular metal foams is a promising heat dissipation approach in high heat flux thermal management. Despite enormous efforts, developing an enhanced thermal strategy that could improve the nucleation site density for metal foam with low PPI, reduce bubble–releasing resistance for the ones with high PPI, and prevent the premature occurrence of CHF remains challenging. Herein, a powerful active reinforcement technique utilizing an electrostatic field to promote pool boiling of cellular metal foams is proposed. Results demonstrate the bubble–releasing density and ONB of metal foams are significantly improved with the increment of applied voltage. By employing a high–voltage electrostatic field, the CHF of metal foams could be increased by 48–65 % at 8 kV, in contrast to the field–free cases. In addition, visualization data reveal bubble departure frequency of metal foams might be increased by up to 5.41 times and the bubble departure diameter could be reduced by a maximum of 48.13 % under electrostatic fields. New correlations of enhancement ratio in BHTC and CHF for nucleate boiling on metal foams under electrostatic fields are constructed, taking into account the influences of surface tension, pore density, and voltage. The predicted results exhibit good validation against the experimental data.

Effect of high voltage discharge on germination characteristics of vetch seeds at high altitude

High-voltage electrostatic fields and low-temperature plasma technology at atmospheric pressure have an important impact on biological growth promotion. Therefore, a multi-needle-column-plate corona plasma generator is proposed in this paper. The negative corona voltammetry characteristics of multi-needle-plate electrodes and multi-needle-column-plate electrodes with different electrode spacing are investigated experimentally, and the electric field distribution of the device is simulated. The device was also applied to vetch seeds at high altitudes to investigate the effect of discharge on germination and root length. The results show that the introduction of column electrodes can effectively improve the electric field distribution of the device so that the device can provide two modes of high voltage electrostatic field and corona plasma field, and ensure the uniform treatment of seeds when the electrode spacing is 3 cm. The treatment of this device accelerates seed germination and promotes root growth, and is more effective under the combined influence of higher electric field strength, ionic wind generated by the discharge, and the active species than a single factor with a lower electric field, as well as shortening the duration of action. The high voltage electrostatic fields at −3 kV, −6 kV, and −9 kV and the corona discharge plasma fields at −12 kV, −15 kV, and −18 kV can effectively accelerate the germination of vetch seeds as well as promote the root growth under the treatment time of 10 min, 20 min, and 30 min. The optimal conditions were −9 kV for 30 min and −15 kV for 10 min, respectively.

High-Voltage Electrostatic Field Hydrogel Microsphere 3D Culture System Improves Viability and Liver-like Properties of HepG2 Cells.

Three-dimensional (3D) hepatocyte models have become a research hotspot for evaluating drug metabolism and hepatotoxicity. Compared to two-dimensional (2D) cultures, 3D cultures are better at mimicking the morphology and microenvironment of hepatocytes in vivo. However, commonly used 3D culture techniques are not suitable for high-throughput drug screening (HTS) due to their high cost, complex handling, and inability to simulate cell-extracellular matrix (ECM) interactions. This article describes a method for rapid and reproducible 3D cell cultures with ECM-cell interactions based on 3D culture instrumentation to provide more efficient HTS. We developed a microsphere preparation based on a high-voltage electrostatic (HVE) field and used sodium alginate- and collagen-based hydrogels as scaffolds for 3D cultures of HepG2 cells. The microsphere-generating device enables the rapid and reproducible preparation of bioactive hydrogel microspheres. This 3D culture system exhibited better cell viability, heterogeneity, and drug-metabolizing activity than 2D and other 3D culture models, and the long-term culture characteristics of this system make it suitable for predicting long-term liver toxicity. This system improves the overall applicability of HepG2 spheroids in safety assessment studies, and this simple and controllable high-throughput-compatible method shows potential for use in drug toxicity screening assays and mechanistic studies.

Effects of different electrostatic field intensities assisted controlled freezing point storage on water holding capacity of fresh meat during the early postmortem period

In this study, the effect of different intensity electrostatic fields on the water holding capacity (WHC) of fresh meat during the early postmortem period in controlled freezing point storage (CFPS) were investigated. Significantly lower cooking loss were found in low voltage electrostatic field (LVEF) and high voltage electrostatic field (HVEF) compared to the control group (CK) (p < 0.05). The myofibril fragmentation index and microstructure results suggested that the sample under HVEF treatment remained relatively intact. It has been revealed that the changes in actomyosin properties under electrostatic field treatment groups were due to the combination and dissociation of actomyosin binding into myofilament concentration, which consequently affects the muscle WHC. The study further demonstrated that the electrostatic field, especially HVEF, might increase the WHC of fresh meat by affecting the distribution of water molecules and physiochemical properties of actomyosin during the early postmortem period.

An airflow-driven system for scalable production of nano-microfiber wrapped triboelectric yarns for wearable applications

Nanofibers, with their large aspect ratio, high specific surface area, and high porosity, hold great promise for applications in textile materials, biomedicine, and smart wearables. Currently, the primary method for producing nanofibers is electrospinning. However, this method carries operational risks due to the use of high-voltage electrostatic fields, and it is not suitable for large-scale production due to low efficiency. To address these challenges, we propose an air-driven spinning system that combines solution blow spinning and vortex tubes for the scalable production of polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) nano-microfiber wrapped conductive yarn. The airbrushing machine allows for high-speed production of PVDF-TrFE nano-microfibers through solution blow spinning, with a maximum production rate of approximately 36 ml/h. The vortex tubes apply rotation and twist to the core yarn using high-speed airflow to bond the nano-microfibers to core yarn. By optimizing the process, we achieve a tight integration between the outer layer of nano-microfibers and the inner layer of conductive core yarn, imparting water repellency, flexibility, washability, air permeability, and a certain level of abrasion resistance to the resulting yarn. We demonstrate the applications of this yarn as triboelectric nanogenerators, including energy harvesting and self-powered sensing. Furthermore, we employ this method to prepare stretchable self-generating triboelectric yarn. This air-driven spinning system overcomes the limitations of electrospinning, providing a scalable and efficient method for the production of nano-microfiber-wrapped yarns with various functional properties.

High-voltage electrostatic field combined with light-emitting diode irradiation: A new method for optimizing the quality of modified atmosphere packaged pakchoi

Pakchoi is one of the most popular leafy vegetables for fleet crews. Modified atmosphere packaging (MAP), most commonly used on ships today, can only extend the shelf life of pakchoi by up to 25 days, far short of the requirements for ocean voyages (>50 days). The objective of this study was to use a combination of emerging non-thermal physical fields (high voltage electrostatic field (HVEF), light emitting diode (LED) irradiation) and modified atmosphere packaging, acting on structural changes caused by external energy field and the molecular changes caused by signal molecular transfer, respectively, to produce a superimposed effect on the pakchoi thereby extending it shelf life to a predetermined target. The treatment maintained the chlorophyll content, ascorbic acid content, hardness and membrane system integrity of packaged pakchoi, effectively reducing respiration rate and polyphenol oxidase activity. Electronic nose and low-field NMR analyses also confirmed better flavor and less water migration in pakchoi. Hierarchical cluster analysis (HCA) revealed that pakchoi stored for 25 days could still be classified in the same category as fresh samples. The results showed that the shelf life of the shipboard pakchoi was successfully extended to 50 days, proving that the synergistic preservation treatment has promising applications.

Biochemistry behind firmness retention of jujube fruit by combined treatment of acidic electrolyzed water and high-voltage electrostatic field.

Harvested jujube (Zizyphus jujuba Mill) is prone to softening due to active metabolism. This study investigated the effects of acidic electrolyzed water (AEW), high-voltage electrostatic field (HVEF) and their combination (AEW+HVEF) on softening and associated cell wall degrading enzymes (CWDEs), cell membrane integrity and antioxidant system of 'Huping' jujube during storage at 0±1°C. The results indicated that fruit subjected to AEW+HVEF, AEW or HVEF treatments maintained firmness 15.7%, 10.7%, and 5.3% higher than that of untreated control fruit at the end of 90days cool storage. Fruit treated with AEW+HVEF could better maintain cell membrane integrity and exhibit lower activities of CWDEs and higher antioxidant capacity than that treated with either AEW or HVEF. Correlation analysis suggested that inhibition of softening was associated with reduction of CWDEs activities, and maintenance of membrane integrity and antioxidant system.