Lutein fortification of wheat bread with marigold powder: impact on rheology, water dynamics, and structure.

BACKGROUND: Demands for foods conducive to eye health have been on the increase in the global healthcare sector. Marigold powder as a major source of lutein was utilized to produce lutein-fortified breads for ocular health. The physicochemical characteristics of the doughs and breads were investigated in terms of rheology, water mobility, and protein secondary structures. RESULTS: The incorporation of marigold powder decreased the water absorption of doughs without significantly altering thermomechanical properties. With a range of fortification levels (1-3%), marigold powder led to decreased storage and loss modulus of doughs by weakening their gluten network, which was supported by their T2 relaxation times. The resistance of the doughs weakened with increasing levels of marigold powder, while their extensibilities significantly incremented. Fourier transform infrared spectral deconvolution revealed the changes in wheat protein structures upon marigold powder incorporation, in which the proportion of ß-turn increased at the expense of ß-sheet ratio. The breads with marigold powder displayed increased specific volume from 4.034 to 4.368 mL g-1 , accompanied by softer textures. The baking process led to heat-induced losses in lutein concentration of less than 10% within the crumb and approximately 30% in the crust. CONCLUSION: The use of marigold powder induced changes in protein secondary structure and extensional features of doughs, contributing to increased loaf volume and softer texture. Overall, this study provides fundamental information on the rheological and structural effects of marigold powder in a wheat bread system, consequently encouraging the food industry to utilize marigold power as a functional food ingredient. © 2023 Society of Chemical Industry.

The effect of physico-chemical treatment in reducing Listeria monocytogenes biofilms on lettuce leaf surfaces.

The purpose of this research was to characterize Listeria monocytogenes from several environmental and clinical sources and assess the efficacy of single and combined physico-chemical treatments in reducing biofilm on lettuce leaves. PCR analysis of L. monocytogenes isolates collected from different clinical (10 strains) and environmental sources (12 strains) was used to look for the presence of one Listeria-specific gene and five virulence genes. Biofilms of L. monocytogenes were developed on lettuce leaves over 24 h. A 5-min ultrasound and a 300-ppm sodium hypochlorite (NaOCl) wash resulted in similar reductions in cell numbers of 0.82 log CFU cm-2. For chlorine dioxide (ClO2) at 60 ppm, the cell numbers were reduced by ∼5.45 log CFU cm-2. A combined treatment of 5 min of ultrasound plus 300 ppm NaOCl or 40 ppm ClO2, provided maximal efficacy, reducing the number of L. monocytogenes on the lettuce surface to non-detectable levels. Therefore, ClO2 has the potential to replace NaOCl for the disinfection of food products in the food industry.

Understanding the Origin of Highly Selective CO2 Electroreduction to CO on Ni,N-doped Carbon Catalysts.

Ni,N-doped carbon catalysts have shown promising catalytic performance for CO2 electroreduction (CO2 R) to CO; this activity has often been attributed to the presence of nitrogen-coordinated, single Ni atom active sites. However, experimentally confirming Ni-N bonding and correlating CO2 reduction (CO2 R) activity to these species has remained a fundamental challenge. We synthesized polyacrylonitrile-derived Ni,N-doped carbon electrocatalysts (Ni-PACN) with a range of pyrolysis temperatures and Ni loadings and correlated their electrochemical activity with extensive physiochemical characterization to rigorously address the origin of activity in these materials. We found that the CO2 R to CO partial current density increased with increased Ni content before plateauing at 2 wt % which suggests a dispersed Ni active site. These dispersed active sites were investigated by hard and soft X-ray spectroscopy, which revealed that pyrrolic nitrogen ligands selectively bind Ni atoms in a distorted square-planar geometry that strongly resembles the active sites of molecular metal-porphyrin catalysts.

Efficacy of UV-TiO2 photocatalysis technology for inactivation of Escherichia coli K12 on the surface of blueberries and a model agar matrix and the influence of surface characteristics.

Surface disinfection of fresh blueberries is an important food safety challenge due to the delicate texture and short shelf life of these small fruits. A newly designed water-assisted photocatalytic reactor was developed for disinfection of fruits with a delicate texture and complex surface characteristics. Efficacy of UV-TiO2 photocatalysis was evaluated in comparison with UV alone for inactivation of Escherichia coli K12 (as a surrogate for Escherichia coli O157:H7) inoculated onto the surface of the blueberry skin, calyx, and an experimentally prepared agar matrix that was used as a model matrix. Influence of surface characteristics such as surface hydrophobicity and surface free energy on bacterial adhesion were also investigated. The initial bacterial population on all surfaces was approximately 7.0 log CFU/g. UV-TiO2 photocatalysis (4.5 mW/cm2) for 30 s achieved comparatively higher bacterial reductions of 5.3 log and 4.6 log CFU/g on blueberry skin and agar matrix surfaces, respectively, than 4.5 log and 3.4 log CFU/g reductions for UV alone (6.0 mW/cm2). Total phenolic and total anthocyanin contents of fruits were significantly increased after both UV-TiO2 and UV treatments, compared with water washed control fruits. UV-TiO2 photocatalysis technology is a non-chemical and residue-free method with reduced water usage for surface disinfection of fresh blueberries.

Self-Assembled NiO/Ni(OH)2 Nanoflakes as Active Material for High-Power and High-Energy Hybrid Rechargeable Battery.

Herein, a proof-of-concept of novel hybrid rechargeable battery based on electrochemical reactions of both nickel-zinc and zinc-air batteries is demonstrated using NiO/Ni(OH)2 nanoflakes self-assembled into mesoporous spheres as the active electrode material. The hybrid battery operates on two sets of fundamentally different battery reactions combined at the cell level, unlike in other hybrid systems where batteries of different reactions are simply connected through an external circuitry. As a result of combining nickel-zinc and zinc-air reactions, the hybrid battery demonstrates both remarkably high power density (volumetric, 14 000 W L(-1); gravimetric, 2700 W kg(-1)) and energy density of 980 W h kg(-1), significantly outperforming the performances of a conventional zinc-air battery. Furthermore, the hybrid battery demonstrates excellent charge rate capability up to 10 times faster than the rate of discharge without any capacity and voltage degradations, which makes it highly suited for large-scale applications such as electric vehicle propulsion and smart-grid energy storage.

Dust particles-induced intracellular Ca2+ signaling and reactive oxygen species in lung fibroblast cell line MRC5.

Epidemiologic interest in particulate matter (PM) is growing particularly because of its impact of respiratory health. It has been elucidated that PM evoked inflammatory signal in pulmonary epithelia. However, it has not been established Ca2+ signaling mechanisms involved in acute PM-derived signaling in pulmonary fibroblasts. In the present study, we explored dust particles PM modulated intracellular Ca2+ signaling and sought to provide a therapeutic strategy by antagonizing PM-induced intracellular Ca2+ signaling in human lung fibroblasts MRC5 cells. We demonstrated that PM10, less than 10 µm, induced intracellular Ca2+ signaling, which was mediated by extracellular Ca2+. The PM10-mediated intracellular Ca2+ signaling was attenuated by antioxidants, phospholipase blockers, polyADPR polymerase 1 inhibitor, and transient receptor potential melastatin 2 (TRPM2) inhibitors. In addition, PM-mediated increases in reactive oxygen species were attenuated by TRPM2 blockers, clotrimazole (CLZ) and N-(p-amylcinnamoyl) anthranilic acid (ACA). Our results showed that PM10 enhanced reactive oxygen species signal by measuring DCF fluorescence and the DCF signal attenuated by both TRPM2 blockers CLZ and ACA. Here, we suggest functional inhibition of TRPM2 channels as a potential therapeutic strategy for modulation of dust particle-mediated signaling and oxidative stress accompanying lung diseases.

3D Ordered Mesoporous Bifunctional Oxygen Catalyst for Electrically Rechargeable Zinc-Air Batteries.

To enhance energy efficiency and durability, a highly active and durable 3D ordered mesoporous cobalt oxide framework has been developed for rechargeable zinc-air batteries. The bifunctional air electrode consisting of 3DOM Co3 O4 having high active surface area and robust structure, results in superior charge and discharge battery voltages, and durable performance for electrically rechargeable zinc-air batteries.

The Regulatory Role of Rolipram on Inflammatory Mediators and Cholinergic/Adrenergic Stimulation-Induced Signals in Isolated Primary Mouse Submandibular Gland Cells.

Exposure to bacterial lipopolysaccharides (LPS) induces inflammatory signals in salivary glands. We investigated the regulatory role of phosphodiesterase 4 (PDE4) inhibitor rolipram on inflammatory mediators and cholinergic/adrenergic stimulation-induced intracellular Ca(2+) signaling in salivary acinar and ductal cells. Submandibular gland (SMG) expressed PDE4A through 4D mRNA and PDE4 was localized in the luminal membrane of SMG. LPS induced Ca(2+) signaling and ROS production in SMG. Treatment with rolipram blocked LPS-induced Ca(2+) increase and ROS production. The application of histamine evoked Ca(2+) signals and ROS production, which were attenuated by rolipram in SMG cells. Moreover, LPS-induced NLRP3 inflammasome and cleaved caspase-1 were inhibited by rolipram. The inhibitory role of rolipram in ROS-induced Ca(2+) signaling was mainly observed in acinar cells and not in ductal cells. Rolipram also protected SMG acinar but not ductal cells from LPS-induced cell membrane damage. In the case of cholinergic/adrenergic stimulation, carbachol/isoproterenol-induced Ca(2+) signals were upregulated by the treatment of rolipram in SMG. In the case of cAMP-dependent ductal bicarbonate secretion by rolipram, no effect was observed on the modulation of ductal chloride/bicarbonate exchange activity. Rolipram could suppress the inflammatory signals and could be a potential therapeutic strategy against LPS-induced inflammation to protect the salivary gland cells.

Microbial decontamination of red pepper powder by cold plasma.

Effects of the microwave-powered cold plasma treatments (CPTs) on the inhibition of microorganisms in red pepper powder, including Aspergillus flavus and Bacillus cereus spores, were investigated. Combinations of heat treatment with CPT were investigated for the inhibition of B. cereus spores on the powder. The number of A. flavus was reduced by 2.5 ± 0.3 log spores/g by the CPT with nitrogen at 900 W and 667 Pa for 20 min. CPT at 900 W and 667 Pa for 20 min inhibited naturally occurring total aerobic bacteria in the red pepper powder by approximately 1 log CFU/g. B. cereus spores were inhibited (3.4 ± 0.7 log spores/g reduction) only when heat treatment at 90 °C for 30 min was integrated with the CPT using a helium-oxygen gas mixture at 900 W. Fermi's model and Weibull model adequately described the inhibition of A. flavus on the red pepper powder by the CPT. The changes in treatment temperature and water activity were less than 5.0 °C (initial temperature: 23.8 °C) and 0.22, respectively, and were affected by both treatment power and time (P < 0.05). The CPTs have demonstrated the potential to reduce the microbial counts of red pepper powder and other powder products.

Effects of Pulsed Electric Field on Meat Tenderization and Microbial Decontamination: A Review.

This review sought to categorize studies on meat tenderization and safety through pulsed electric field (PEF) treatment, with a particular focus on reconciling conflicting findings regarding the tenderization effect (i.e., the primary outcome of PEF treatment) and to discuss the underlying mechanisms of these effects. While the tenderization effect may vary depending on the homogeneity of PEF treatment and variations in the conditions of texture measurements, the protein associated with tenderization was degraded by PEF treatment in most studies. PEF technology enables the delivery of a high voltage for a brief duration, typically in the microsecond range, making it a non-thermal technology. One of the distinct advantages of PEF is its ability to preserve the freshness of meat due to its exceptionally short treatment time. While PEF studies have traditionally centered on pasteurizing liquid foods, research on its application to meat is steadily expanding. Therefore, this review aims to elucidate the mechanisms of PEF and provide current insights into the applications of this technology for meat tenderization and microbial inactivation.

Effects of Pulsed Electric Field Pretreatment on Black Tea Processing and Its Impact on Cold-Brewed Tea.

This study applied pulsed electric fields (PEFs) to accelerate the withering and drying processes during cold-brewed black tea production. PEF pretreatment was administered at 1.0, 1.5, and 2.0 kV/cm electric field strengths, combined with varying withering times from 8 to 12 hr. During the 12-hour withering process, the redness value (a*) and total color change (∆E) of PEF-treated leaves significantly increased (p < 0.05). Furthermore, the homogenous redness of tea leaves during fermentation depended on the PEF strength applied. In addition, PEF pretreatment remarkably reduced the drying time, up to a 50% reduction at a 2.0 kV/cm field strength. Additionally, the 2.0 kV/cm PEF-pretreated black tea exhibited a notable 42% increase in theaflavin (TF) content and a 54% increase in thearubigin (TR) content. Sensory evaluation scores were highest for black tea that received PEF pretreatment at 2.0 kV/cm. These findings highlight the significant potential of PEFs in enhancing the efficiency of withering and drying processes while positively impacting the physicochemical and sensory properties of cold-brewed black tea.

The Effects of Jet-Milling and Pulsed Electric Fields on the Preservation of Spinach Juice Lutein Contents during Storage.

This study aimed to investigate the effects of jet-milling on the lutein extraction contents of spinach powder (SP), as well as the effects of pulsed electric field (PEF), as a non-thermal pasteurization technology, on the preservation of spinach juice (SJ) lutein contents. SP particles were divided into SP-coarse (Dv50 = 315.2 µm), SP-fine (Dv50 = 125.20 µm), and SP-superfine (Dv50 = 5.59 µm) fractions, and SP-superfine was added to SJ due to its having the highest contents of lutein extract. PEFs and thermal treatment were applied to evaluate the effects of preserving the lutein content of PEF during storage (25 days). The juice was then designated as untreated (no pasteurization), PEF-1,2 (SJ treated with PEF 20 kV/cm 110 kJ/L, 150 kJ/L), or Thermal-1,2 (SJ treated with 90 °C, 10 min and 121 °C, 15 min). The sizes and surface shapes of the superfine SP particles were more homogeneous and smoother than those of the other samples. SJ made with SP-superfine and treated with PEF had the highest lutein content and antioxidant activities among the group during storage. A complex of jet-milling and PEF could have great potential as a method to improve the lutein contents of lutein-enriched juice in the food industry.

Longevous Cycling of Rechargeable Zn-Air Battery Enabled by "Raisin-Bread" Cobalt Oxynitride/Porous Carbon Hybrid Electrocatalysts.

Developing commercially viable electrocatalyst lies at the research hotspot of rechargeable Zn-air batteries, but it is still challenging to meet the requirements of energy efficiency and durability in realistic applications. Strategic material design is critical to addressing its drawbacks in terms of sluggish kinetics of oxygen reactions and limited battery lifespan. Herein, a "raisin-bread" architecture is designed for a hybrid catalyst constituting cobalt nitride as the core nanoparticle with thin oxidized coverings, which is further deposited within porous carbon aerogel. Based on synchrotron-based characterizations, this hybrid provides oxygen vacancies and Co-Nx -C sites as the active sites, resulting from a strong coupling between CoOx Ny nanoparticles and 3D conductive carbon scaffolds. Compared to the oxide reference, it performs enhanced stability in harsh electrocatalytic environments, highlighting the benefits of the oxynitride. Furthermore, the 3D conductive scaffolds improve charge/mass transportation and boost durability of these active sites. Density functional theory calculations reveal that the introduced N species into hybrid can synergistically tune the d-band center of cobalt and improve its bifunctional activity. As a result, the obtained air cathode exhibits bifunctional overpotential of 0.65 V and a battery lifetime exceeding 1350 h, which sets a new record for rechargeable Zn-air battery reported so far.

Tenderization of Beef Semitendinosus Muscle by Pulsed Electric Field Treatment with a Direct Contact Chamber and Its Impact on Proteolysis and Physicochemical Properties.

In this study, the effects of pulse electric field (PEF) treatment on the tenderization of beef semitendinosus muscle were investigated. An adjustable PEF chamber was designed to make direct contact with the surface of the beef sample without water as the PEF-transmitting medium. PEF treatment was conducted with electric field strengths between 0.5 and 2.0 kV/cm. The pulse width and pulse number were fixed as 30 µs and 100 pulses, respectively. The impedance spectrum of PEF-treated beef indicated that PEF treatments induced structural changes in beef muscle, and the degree of the structural changes was dependent on the strength of the electric field. Cutting force, hardness, and chewiness were significantly decreased at 2.0 kV/cm (35, 37, and 34%, respectively) (p < 0.05). Troponin-T was more degraded by PEF treatment at 2.0 kV/cm intensity (being degraded by 90%). The fresh quality factors such as color and lipid oxidation were retained under a certain level of PEF intensity (1.0 kV/cm). These findings suggest that PEF treatment could tenderize beef texture while retaining its fresh quality.

Superfine Marigold Powder Improves the Quality of Sponge Cake: Lutein Fortification, Texture, and Sensory Properties.

This study aimed to investigate and optimize the quality and sensory properties of baked products with lutein-enriched marigold flower powder (MP). Lutein-enriched marigold flowers produced via hydroponic methods using LED lights were used as a functional material in sponge cakes to increase lutein content. MP particles were divided into coarse (Dv50 = 315 µm), fine (Dv50 = 119 µm), and superfine MP (Dv50 = 10 µm) fractions and added to the sponge cake after being designated to control (sponge cake prepared without MP), coarse MPS (sponge cake prepared with coarse MP), fine MPS (sponge cake prepared with fine MP), and superfine MPS (sponge cake prepared with superfine MP) groups. The sizes and surface properties of superfine MP particles were more homogeneous and smoother than the other samples. As the particle size decreased, the specific volume increased, whereas baking loss, hardness, and chewiness of the sponge cake decreased. Superfine MP and superfine MPS had the highest lutein content. The flavor of marigold and the overall acceptability of sponge cake with superfine MP were 7.90 ± 0.97 and 7.55 ± 0.76, which represents the highest values among the samples. The results of this study have shown that jet milling can contribute to improvements in texture, lutein content, and sensory qualities for baked products with MP.

A Pulsed Electric Field Accelerates the Mass Transfer during the Convective Drying of Carrots: Drying and Rehydration Kinetics, Texture, and Carotenoid Content.

The pulsed electric field (PEF) is a non-thermal food processing technology that induces electroporation of the cell membrane thus improving mass transfer through the cell membrane. In this study, the drying and rehydration kinetics, microstructure, and carotenoid content of carrot (Daucus carota) pretreated by PEF during convective drying at 50 °C were investigated. The PEF treatment was conducted with different field strengths (1.0-2.5 kV/cm) using a fixed pulse width of 20 µs and at a pulse frequency of 50 Hz. The PEF 2.5 kV/cm showed the shortest drying time, taking 180 min, whereas the control required 330 min for the same moisture ratio, indicating a 45% reduction in drying time. The rehydration ability also increased as the strengths of PEF increased. PEF 2.5 kV/cm resulted in 27.58% increase in moisture content compared to the control after rehydration (1 h). Three mathematical models were applied to the drying and rehydration data; the Page and Peleg models were selected as the most appropriate models to describe the drying and rehydration kinetics, respectively. The cutting force of the sample was decreased as the strength of PEF increased, and a more homogeneous cellular structure was observed in the PEF pretreatment group. The reduction in drying time by PEF was beneficial to the carotenoid content, and PEF 2.5 kV/cm showed the highest preservation content of carotenoid. Overall, these results suggested that the pretreatment of PEF and the drying and rehydration rate influence the quality of products, functional components, and cellular structure.

Hyaluronic acid hydrolysis using vacuum ultraviolet TiO2 photocatalysis combined with an oxygen nanobubble system.

Advanced technologies for producing high-quality low molecular weight hyaluronic acid (LMW-HA) are required from the perspective of cost-efficiency and biosafety. Here, we report a new LMW-HA production system from high molecular weight HA (HMW-HA) using vacuum ultraviolet TiO2 photocatalysis with an oxygen nanobubble system (VUV-TP-NB). The VUV-TP-NB treatment for 3 h resulted in a satisfactory LMW-HA (approximately 50 kDa measured by GPC) yield with a low endotoxin level. Further, there were no inherent structural changes in the LMW-HA during the oxidative degradation process. Compared with conventional acid and enzyme hydrolysis methods, VUV-TP-NB showed similar degradation degree with viscosity though reduced process time by at least 8-fold. In terms of endotoxin and antioxidant effects, degradation using VUV-TP-NB demonstrated the lowest endotoxin level (0.21 EU/mL) and highest radical scavenging activity. This nanobubble-based photocatalysis system can thus be used to produce biosafe LMW-HA cost-effectively for food, medical, and cosmetics applications.

Simulation of contamination and elimination of Escherichia coli, Listeria monocytogenes, and Murine norovirus 1 (MNV-1) from the washing process when handling of potatoes.

Root vegetables, which are in close contact with soil, are particularly vulnerable to soil contamination or decay as they can be contaminated from multiple sources, including primary production and processing. This study investigated effective washing conditions to reduce the microbial contamination of potatoes by using soaking and shaking in the washing process. The reduction of Escherichia coli, Listeria monocytogenes, and Murine norovirus 1 (MNV-1) in four washing processes (soaking only, shaking only, combined soaking-shaking I, and combined soaking-shaking I-shaking II) were compared. The numbers of E. coli and L. monocytogenes decreased by 0.55 and 0.49 log CFU/g after shaking only, 1.96 and 1.80 log CFU/g after soaking, 2.07 and 1.67 log CFU/g after soaking-shaking I, and 2.42 and 1.90 log CFU/g after soaking-shaking I-shaking II, respectively. The combined process reduced the microbial contamination more efficiently than shaking only. The reduction of E. coli in the washing process was higher than that of L. monocytogenes by approximately 0.5 logs. MNV-1 showed a reduction in the soaking and shaking steps by 1.34 and 1.98 log GC/100 g, with no significant reduction observed after the combination process. A combined process of soaking-shaking I-shaking II was effective to eliminate E. coli, L. monocytogenes, and MNV-1 from potatoes during the handling and washing process.

Effects of high hydrostatic pressure on structure and colour of red ginseng (Panax ginseng).

BACKGROUND: The conventional method of processing ginseng (Panax ginseng) roots into red ginseng involves mainly heating and drying processes. In the present study, this method was modified by using high hydrostatic pressure (HHP) to improve the physicochemical characteristics of red ginseng. RESULTS: The HHP process (600 MPa for 1 min) significantly improved the histological properties of red ginseng by increasing cellular disruption and release of cell contents. The total reducing sugar content was significantly (P < 0.05) higher (increased from 10.67 to 15.25 mg g(-1)) in red ginseng processed at 600 MPa for 1 min. Similarly, the total free amino acid content also increased significantly (from 2.81 to 7.77 mg g(-1)). The HHP process resulted in superior and more even colouration and gave an attractive visual appearance to red ginseng. The optical density at 420 nm and Hunter's colour a value (redness) of extracts prepared from red ginseng increased significantly (P < 0.05) with the application of HHP. CONCLUSION: HHP-processed red ginseng has significantly higher reducing sugar and free amino acid contents together with a more compact cell structure and superior visual quality (brighter red colour). Hence the application of HHP in red ginseng processing can result in ginseng products of improved quality compared with those obtained by the conventional method.

Designing a Zn-Ag Catalyst Matrix and Electrolyzer System for CO2 Conversion to CO and Beyond.

CO2 emissions can be transformed into high-added-value commodities through CO2 electrocatalysis; however, efficient low-cost electrocatalysts are needed for global scale-up. Inspired by other emerging technologies, the authors report the development of a gas diffusion electrode containing highly dispersed Ag sites in a low-cost Zn matrix. This catalyst shows unprecedented Ag mass activity for CO production: -614 mA cm-2 at 0.17 mg of Ag. Subsequent electrolyte engineering demonstrates that halide anions can further improve stability and activity of the Zn-Ag catalyst, outperforming pure Ag and Au. Membrane electrode assemblies are constructed and coupled to a microbial process that converts the CO to acetate and ethanol. Combined, these concepts present pathways to design catalysts and systems for CO2 conversion toward sought-after products.