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• Bilayer passive cooler comprised aerogel and hydrogel for daytime passive cooling. • Aerogel achieved daytime radiative cooling and thermal insulation. • Aerogel was hydrophobic and exhibited self-cleaning function. • Hydrogel achieved daytime evaporative cooling and nighttime moisture capture. • Evaporative cooling efficiency was regulated by aerogel thicknesses. The combination of daytime radiative and evaporative cooling has been considered a promising complementary technology for lessening greenhouse gas emissions and global energy consumption. However, this cooling strategy is impaired by environmental heat; its evaporative cooling capacity and cooling time are uncontrollable, and water consumption is significant. Inspired by the cactus's ability to cope with arid and hot environments, the bilayer passive cooler (BPC) consisting of aerogel with particle coating and hydrogel with hygroscopic agent was developed to overcome these challenges. The aerogel with particle coating possessed high solar reflectance (∼0.95), strong infrared radiation (∼0.94), low thermal conductivity (∼42 mW m−1 K−1), and great hydrophobicity (CA = 138°) to perform daytime radiative cooling, thermal insulation, and self-cleaning function. The hydrogel with hygroscopic agent achieved the nighttime moisture capture. The evaporative cooling capacity and cooling time could be regulated by the aerogel and hydrogel thicknesses. The field test showed that the BPC achieved a temperature drop of ∼ 8℃ compared to the ambient temperature of ∼ 30℃ and a cooling power of ∼ 222 W m−2 under the sunlight. Thus, the present study should open a new daytime passive cooling technology pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dual-bioinspired photothermal eutectogels are prepared for passive anti-freezing. • Natural deep eutectic solvent can remarkably increase nanofiller loading capacity. • Molecular dynamics simulation proves uniform dispersion of hCNTs in the system. • Uniform hCNTs distribution abates stress concentration and load transfer failure. • Eutectogels show desirable performance in anti-frosting, anti-icing, and deicing. Icing and frosting always cause troubles in present-day human activities, appealing for effective anti-freezing strategies to break through the bottleneck. Inspired by "predominant metabolites in the body fluid of cold-tolerant animals" and "poikilotherms that increase body temperature by absorbing solar energy", natural deep eutectic solvents (NADES) and carbon nanotubes (CNTs) were incorporated within calcium alginate (CA) backbone to fabricate dual-bioinspired and ultra-flexible photothermal eutectogels (CNTs/NADES@CA). Normal CNTs (nCNTs) and hydroxylated CNTs (hCNTs) were used to investigate the effects of hydrogen-bonding networks of NADES on the dispersal/aggregation behaviours of nCNTs/hCNTs. Molecular dynamics (MD) simulation proved that hCNTs could form intense hydrogen-bonding interactions with NADES and disperse more uniformly, ultimately contributing to better mechanical properties. Spectral characteristics covering solar absorption and infrared emissivity showed that higher nanofiller loading could cause increased infrared emissivity, leading to more thermal energy loss during photothermal conversion. Besides, moisture absorption–desorption tests further confirmed the excellent function reproducibility and sustainability of the materials. One of the hCNTs-based eutectogels (4%-hCNTs) behaving the best in photothermal conversion was selected for anti-freezing tests concerning anti-frosting, anti-icing, and deicing capacities, announcing that the CNTs/NADES@CA could be highly efficient for passive anti-freezing. This study proposed a highly efficient nanofiller dispersion strategy enabled by NADES to fabricate ultra-flexible photothermal eutectogel by a physically simple method, and it is hoped that this work could open up new avenues for bioinspired materials and attract more concerns for the proposed dual-bioinspired anti-freezing strategy. [ABSTRACT FROM AUTHOR]

Constant power microwave heating (CPMH) based on solid-state generators, a new microwave heating system, shows better repeatability than traditional microwave heating (TMH) powered by magnetron when performing experiments, while its detailed heating patterns and field distribution are still not fully understood. In this study, numerical simulations for model juice (about 1–5 mL) heated by CPMH and TMH systems were carried out to compare the heating performance. The simulation was performed through coupling electromagnetic, thermal and fluid fields, using a laminar flow model to simulate the flow behaviour of the model juice during the heating operation. Both surface temperature distributions and inner point temperatures were investigated for model validation, and the simulated data agreed well with the experimental ones, indicating that the modelling was rational and correct. Results showed that CPMH gave higher heating efficiency and better temperature uniformity, which was verified by determining both inner point temperature and surface temperature distribution. Besides, influences of sample volume and microwave input power on the heating performance of the CPMH system were studied, suggesting that greater sample volume could cause worse temperature uniformity, although a faster temperature increase was observed. When fixing total microwave input energy to 3 kJ, different input powers were found to achieve similar final average volumetric temperatures (50.46 °C–51.22 °C) but significantly different heating uniformity (final coefficient of temperature variance: 0.065–0.115), indicating that smaller microwave input power could contribute to better heating uniformity. It is hoped that this study could provide references to further understand the heating effects of CPMH systems, leading to better design and upgrade for microwave heating systems. • Model juice heated by constant power microwave heating (CPMH) system was simulated. • Heating performance of traditional microwave heating (TMH) system was compared. • CPMH showed higher heating efficiency and better temperature uniformity than TMH. • Central zone of the model juice gained more microwave energy for heating. • For CPMH, greater power made heating faster but decreased temperature evenness. [ABSTRACT FROM AUTHOR]

• Composite hydrogel was developed for sustainable daytime passive cooling. • Mechanical properties of hydrogel were improved by highly entangled structure. • Hydrogel achieved coupling effects of daytime radiative and evaporative cooling. • Hydrogel realized atmospheric water harvesting at night for next evaporation. • Relationship of daytime passive cooling with night time rehydration was revealed. Daytime passive cooling technology supported by coupling effects of daytime radiative cooling and evaporative cooling has drawn significant attention for alleviating the burdens of energy consumption and greenhouse gas emissions. Incorporating a hygroscopic agent allows the daytime radiative/evaporative cooler to replenish water itself at night, thus ensuring evaporative cooling during the daytime. However, the mechanism of the relationship between daytime passive cooling and nighttime rehydration is not fully understood. Besides, the design of circulating daytime radiative/evaporative coolers is segmented at present, and the poor mechanical properties of hydrogel restrict the practical application. Hence, a tough and elastic hydrogel with a highly entangled structure was prepared by dense polyacrylamide chains, exhibiting the 18-fold tensile stress and 9-fold compressive stress of the control group. Integrating zirconium dioxide (ZrO 2) particles as a spectral regulator, the composite hydrogel possessed solar reflectance of 0.90 and mid-infrared emission of 0.88, realising daytime radiative cooling. After swelling in lithium bromide (LiBr) solution, the composite hydrogel achieved a cycle of daytime evaporative cooling and nighttime rehydration. Besides, the effects of LiBr concentrations on the evaporation and hygroscopicity of the composite hydrogel were investigated. Furthermore, two indoor experiments and one outdoor field test were performed, and the findings suggested that the design of strong hygroscopicity and effective evaporation was a contradiction, and it is crucial to narrow the gap between evaporation and rehydration instead of only pursuing the best cooling performance to achieve sustainable daytime passive cooling. Thus, it is hoped that this study could broaden the field of sustainable daytime passive cooling technologies. [ABSTRACT FROM AUTHOR]

• Nanocomposite hydrogel was developed for daytime passive cooling. • Mechanical, swelling, and hygroscopic properties of hydrogel were analyzed. • Combined effects of radiation and evaporation were achieved. • Radiative and evaporative cooling powers were determined. • Hydrogel showed effective building cooling and ice-food preservation during daytime. Both radiative and evaporative cooling as passive cooling technologies can reduce dependence on active cooling technologies. However, most reported studies investigated radiative and evaporative cooling separately, and significant challenges still remain in achieving highly efficient combined radiative and evaporative cooling. Hence, a polyacrylamide/polyvinyl alcohol hydrogel with nanoparticles (NPs/NADES@PAAm/PVA) was fabricated by natural deep eutectic solvent for highly efficient daytime passive cooling. The NPs/NADES@PAAm/PVA with a solar reflectance of ∼0.95 and an atmospheric emissivity of ∼0.92 could realize daytime radiative cooling. Besides, the NPs/NADES@PAAm/PVA possessed robust mechanical strength, excellent flexibility, and great rehydration. After water absorption, both swollen NPs/NADES@PAAm/PVA and hygroscopic NPs/NADES@PAAm/PVA could simultaneously achieve radiative and evaporative cooling. Outdoor experiments demonstrated that the NPs/NADES@PAAm/PVA, swollen NPs/NADES@PAAm/PVA, and hygroscopic NPs/NADES@PAAm/PVA obtained an average temperature drop (Δ T) of ∼2.9, ∼6.2, and ∼3.6 °C under the sunlight, respectively, compared with the ambient temperature of ∼35.0 °C, indicating that the NPs/NADES@PAAm/PVA could achieve a sub-ambient temperature while the swollen and hygroscopic NPs/NADES@PAAm/PVA possessed better cooling performances due to the combined cooling effects. Another outdoor experiment proved that the NPs/NADES@PAAm/PVA had great application potential in building cooling and iced food preservation under sunlight, further promoting passive cooling technology. [ABSTRACT FROM AUTHOR]

Convective heat transfer between a sphere and the surrounding medium and conductive heat transfer within the sphere were numerically modeled at the presence or absence of ultrasound. Different Nusselt ( Nu ) number correlations were evaluated and ultrasound assisted cooling was simulated for different intensities (190–2800 W m −2 ), cooling medium temperatures (−5–−20 °C) and materials (copper and potato). The simulations were compared with experimental data. Both simulations and experimental data revealed that the particle to fluid convective heat transfer rate could be enhanced significantly by the aid of ultrasound irradiation. The results revealed that the selection of an appropriate Nu correlation was critical. With the chosen Nu correlation, the numerical model simulated the experimental data accurately. Ultrasound intensity was also incorporated into the Nu correlation while considering the ultrasonic heat generation in the heat transfer equation, and the simulation profiles matched to experimental profiles very well. The prominent advantage of the model was its ability to estimate the convective heat transfer coefficient at different temperatures. The results of this study are useful in different food and chemical processes involving heat transfer such freezing, chilling, crystallization and heat preservation. [ABSTRACT FROM AUTHOR]

• Treatment induced conformational changes and structural unfolding of peptide chains. • Peptides with increased roughness, surface area and smaller particles were created. • Accelerated hydrolysis produced soluble peptides with improved bioactive properties. • Emulsifying and foaming properties were reduced. • Hydrolysates Functionality was affected by processing conditions and enzyme type. The effects of plasma functionalized water (PFW) and its combination with ultrasound (UPFW) on the functional and bioactive properties of small yellow croaker protein hydrolysates (SYPHs) produced from three enzymes were investigated. Fluorescence and UV–Vis spectroscopy indicated that SYPHs tended to unfold with increasing intensity and shift in wavelengths to more flexible conformations under PFW and UPFW treatments. Particle size distribution and microstructure analysis revealed that treatments could disrupt aggregation of protein molecules to increase the roughness, specific surface area, and decrease the particle size of peptides during hydrolysis. The partially denatured structure of SYPHs induced by treatments increased the susceptibility of the fish proteins to exogenous enzymes, thereby accelerating the hydrolytic process to yield peptides with improved solubility, decreased emulsifying and foaming properties, and improved enzyme-specific antioxidant properties. The results revealed that the functionality of SYPHs was influenced by the treatment method and the enzyme type employed. [ABSTRACT FROM AUTHOR]

Plants constitute the foundation of sustainable environmental systems and human health. However, the limitations of solar radiation and the increased challenges of plant cultivation pose a threat to the environment and human health. In the past years, artificial lighting sources have been a hot topic in many fields, especially in plant cultivation owing to their controlled nature of the conditions. However, traditional artificial lighting sources suffer from unstable light quality, high energy consumption, and a short lifespan, which hinders their widespread use in agricultural farming. In contrast, light conversion technologies offer unparalleled advantages such as high conversion efficiency, stronger light harvesting, good photostability, and superior biocompatibility. With the flourishing development of nanotechnology, nano light conversion agents have been demonstrated to be alternative tools to traditional artificial light sources. Therefore, light conversion agents-guided plant cultivation is a promising strategy in the development of sustainable systems. This review introduces the mechanism and classification of nano light conversion agents and summarises recent advances in the applications of light conversion agents for plant cultivation. The prospects and challenges of light conversion agents are also discussed in the current review. • Light conversion mechanisms and classification of plant cultivation were reviewed. • Applications of light converter platforms for plant cultivation were summarized. • Prospects and challenges in applying nano light conversion agents were presented. [ABSTRACT FROM AUTHOR]

An isoreticular principle guides the directed evolution of domino reactions in MOF nanozymes against antibacterial resistance. The Ce-UiO-66 nanozymes, with linker-dependency on dual hydrolytic and redox mimicry, couple ATP depletion and ROS generation into a unique biofilm microenvironment-responsive prodrug-mimicking domino reaction, enabling the kinetically favourable Ce-UiO-66-NO 2 to effectively target and inhibit MRSA biofilm at the initial bacterial adhesion stage. [Display omitted] • Isoreticular chemistry accelerates the directed nanozyme discovery of Ce-MOFs. • Linker dependence Ce-UiO-66-X modulates dual apyrase and oxidase biomimicry; • Domino effect of the hydrolytic and redox activities in Ce-UiO-66-X is revealed; • Domino reaction in Ce-UiO-66-X couples ATP hydrolysis and ROS generation; • Ce-UiO-66-X enables microenvironment-responsive disinfection of MRSA biofilm. Nanozyme therapy holds promise for overcoming daunting antimicrobial resistance, but skills to target the microbial microenvironment are lacking. Herein, an isoreticular principle was introduced in nanozyme discovery to directedly evolve a domino biomimetic reaction specific to drug-resistant bacterial biofilm. The isoreticular Ce-UiO-66-X (X = BDC, BDC-CH 3 , BDC-OH, BDC-NH 2 , BDC-NO 2 , ADC, Fum) MOFs exhibited linker-dependent mimicry of hydrolytic apyrase and redox oxidase, and the phosphorous reactants (ATP/ADP/AMP/Pi) produced by the ATP hydrolysis could spontaneously activate redox reaction in Ce-UiO-66-X. Evidenced by the representative Ce-BDC-X (X = –NO 2 , -H, and –NH 2) nanozymes, the unique domino reaction of Ce-UiO-66-X could simultaneously deplete ATP molecules and trigger enhanced generation of superoxide radicals at the specific time window in the initial bacterial adhesion stage of methicillin-resistant Staphylococcus aureus (MRSA) biofilm formation. Due to the synergistic nanocatalytic mechanism, possible nanoscale penetration effect, and good biocompatibility, Ce-UiO-66-NO 2 could effectively target and destroy the metabolic microenvironment of MRSA biofilm in vitro and in vivo, reducing the MRSA biofilm viability to as low as 3.64%. This work demonstrates a new prodrug-like enzymodynamic antibacterial therapeutics based on cooperative multienzyme reactivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lysozyme is immobilized on Ti 3 C 2 T X MXene nanosheets modified with polydopamine. • The light-switchable enzymatic antibacterial platform is constructed. • The antibacterial activity against MRSA improves after NIR light irradiation. Being a unique biocatalyst to hydrolyse structural polysaccharides on the cell wall of bacteria, lysozyme can slow down bacterial resistance caused by antibiotic overdose treatments, however, efficient activation of lysozyme activities under pathogenic microenvironments remains challenging. Herein, a bio-interface engineering strategy was proposed for the remote modulation of thermoresistant lysozyme upon rationally designed photothermal nanoplatforms. For this, Ti 3 C 2 T X MXene nanosheets were functionalized by polydopamine (PDA) surface chemistry to enhance photothermal effects and performance durability, during which lysozyme biomacromolecules were immobilized at such a two-dimensional hybrid interface via intermolecular electrostatic affinity. The integrated nanoplatform (denoted as M@P@Lyso), with an optimal high light-to-heat conversion efficiency of 46.88%, realized not only precision control of local heat but also photo-responsive up-regulation for bio-catalysis of laden lysozyme. As a result, in vitro and in vivo antibacterial experiments revealed that M@P@Lyso could effectively inhibit the proliferation of methicillin-resistant Staphylococcus aureus and accelerated wound disinfection of mice with negligible biological toxicities. The outstanding antibacterial activities of M@P@Lyso were attributed to the photo-enhanced lysozyme activity, assisted by bacterial death caused by the mild local hyperthermia and the physical destruction derived from the M@PDA. This work exemplified a solution to the bacterial resistance threats via stimuli-responsive enzymatic nanoplatforms. [ABSTRACT FROM AUTHOR]

• US-FT and MW-FT pretreatments were employed for improving infrared drying of RDFS. • US-FT and MW-FT modified microstructure to increase moisture diffusivity of RDFS. • Betalain and ascorbic acid contents of RDFS were improved by low-temperature US-FT. • High-power MW-FT enhanced color and textural properties of RDFS. • US-FT presented overall enhancements in the quality of RDFS. The effects of thermoultrasound (US-FT), microwave (MW-FT), and room temperature (RT-FT) freeze–thaw pretreatments were evaluated for improving drying kinetics and quality during infrared drying (IRD) of red dragon fruit slices (RDFS). Results indicated that microstructural alterations induced by the different pretreatments improved the moisture removal rate and effective diffusivity, and significantly reduced the drying time. US-FT pretreatments prompted more efficient drying and presented an overall enhancement in the quality of RDFS, particularly at low temperatures of 25 and 50 ℃, while enhancements in TFC, FRAP, and CUPRAC were associated with RT-FT. High-power (500 W) MW-FT pretreatments improved colour and structural properties, while low-power (100, 300 W) improved TPC, TFC, ascorbic acid, betalains, and antioxidant activity. Overall, cellular and chemical alterations prompted by pretreatments improved the drying process but presented adverse effects on betaxanthin. The study presented the fundamental background for improving the IRD of foods from the use of improved thawing approaches during freeze–thaw pretreatments. [ABSTRACT FROM AUTHOR]

In recent years, innovative methods such as ultrasound assisted freezing have been developed in order to improve the freezing process. During freezing of foods, accurate prediction of the temperature distribution, phase ratios, and process time is very important. In the present study, ultrasound assisted immersion freezing process (in 1:1 ethylene glycol–water solution at 253.15 K) of potato spheres (0.02 m diameter) was evaluated using experimental, numerical and analytical approaches. Ultrasound (25 kHz, 890 W m −2 ) was irradiated for different duty cycles (DCs = 0–100%). A finite volume based enthalpy method was used in the numerical model, based on which temperature and liquid fraction profiles were simulated by a program developed using OpenFOAM® CFD software. An analytical technique was also employed to calculate freezing times. The results showed that ultrasound irradiation could decrease the characteristic freezing time of potatoes. Since ultrasound irradiation increased the heat transfer coefficient but simultaneously generated heat at the surface of the samples, an optimum DC was needed for the shortest freezing time which occurred in the range of 30–70% DC. DCs higher than 70% increased the freezing time. DCs lower than 30% did not provide significant effects on the freezing time compared to the control sample. The numerical model predicted the characteristic freezing time in accordance with the experimental results. In addition, analytical calculation of characteristic freezing time exhibited qualitative agreement with the experimental results. As the numerical simulations provided profiles of temperature and water fraction within potatoes frozen with or without ultrasound, the models can be used to study and control different operation situations, and to improve the understanding of the freezing process. [ABSTRACT FROM AUTHOR]

• Hydrogen bonding strength of water in the solutions was analyzed and quantified. • Saccharides could enhance the hydrogen bonding strength of water in the solutions. • Hydrogen bonding strength of water was related to the hydration of saccharides. • Results were verified by T 2 relaxation time of the saccharide solutions. Raman spectroscopy has been employed for studying water structures in biomolecular aqueous solutions for decades but challenges remain to quantify the hydrogen bonding strengths in complex aqueous solution systems. In this study, four kinds of saccharide aqueous solutions were employed to investigate the quantitative relationship between the hydrogen bonding strength of water using confocal Raman microscopy and the Raman spectra of these solutions in the range of 3000–3800 cm−1. Results showed that the enhancement effect of saccharide molecules on the hydrogen bonding strength of water increased with the concentration, and the degree of changes in the strength was related to the hydration capability and partial molal volume of saccharide molecules. An equation based on the average number of hydrogen bonds of water molecule was proposed to quantify the bonding strength in saccharide aqueous solutions with satisfactory accuracy as verified by T 2 relaxation time using nuclear magnetic resonance spectrometer. [ABSTRACT FROM AUTHOR]

[Display omitted] A novel technique for treating grass carp by combining plasma functionalized liquids and ultrasound to inactivate bacteria was developed. The effects of the plasma functionalized liquids (PFL) including plasma functionalized water (PFW) and buffer (PFB) and their respective combination with ultrasound treatment (USPFW and USPFB) on the oxidative and physical qualities of grass carp were also investigated. Individual applications of PFW and PFB significantly reduced the populations of Escherichia coli and Shewanella putrefaciens in the range of 0.31–1.18 log CFU/g, compared with the control with a reduction of 0.18 log CFU/g, while combined treatments of USPFW and USPFB presented additional reductions of 0.05–0.65 log CFU/g , with potential synergy demonstrated for PFW and ultrasound. The treatment resulted in improved biomedical index and nutritional value of fatty acids and lipids, protein structural unfolding, increased lipid oxidation and protein degradation with values within the acceptable limits, and the combined treatment was more effective for retarding the hardness reduction in grass carp, while the colour change was also significantly affected, resulting in increased whiteness. The results indicated that the combined treatments may be a promising approach to improving the quality of seafood products. [ABSTRACT FROM AUTHOR]

• Thermoultrasound-assisted PFB decontamination was optimized for bacteria reduction. • Optimized conditions yielded higher reductions compared with individual treatments. • Predictive models had adequate fitness with temperature variable more significant. • Lipid oxidation and TVB-N after treatment were within limits of fish freshness. • Decontamination was mild on fish microstructure and myofibril degradation. A novel method of thermoultrasound-assisted plasma functionalized buffer (PFB) for decontaminating grass carp was evaluated using the Box–Behnken design (BBD) with processing variables including PFB generating voltage (P V), ultrasound treatment time (U T) and temperature (T P). The predicted models were found to be significant (p < 0.05) and displayed sufficient fitness with experimental data as indicated by non-significant (p > 0.05) lack of fit and high coefficient of determination (R2 ≥ 0.97) values. The optimum decontamination conditions for the responses of S. putrefaciens and S. Typhimurium were P V of 66 V, U T of 14.90 min and T P of 60 ℃, achieving reductions of 4.40 and 3.97 log CFU/g, respectively, with a desirability of 0.998. Among the variables, temperature presented higher significance for inactivating bacteria and the production of volatile basic nitrogen and lipid peroxidation under the optimized conditions were within the limits of freshness for grass carp. Additionally, the effects of PFB and the optimized thermoultrasound-assisted PFB decontamination were mild on the microstructure of grass carp with slight ruptures and loose myofibril structures, indicating the potential of thermoultrasound-assisted PFB for seafood products decontamination with reduced processing time. [ABSTRACT FROM AUTHOR]

• Multi-frequency ultrasound assisted freezing is better than single-frequency. • Increase in the number of ultrasonic frequencies increased cavitation yield. • Multi-frequency ultrasound improved the freezing efficiency of potatoes. • Cell structure of potato was less damaged under multi-frequency ultrasound. • Nutrients of potato were better preserved under multi-frequency ultrasound. The effects of multi-frequency ultrasound assisted freezing on the freezing rate, microstructure, quality properties (drip loss, firmness, total calcium content, l -ascorbic acid content and total phenol content) of potatoes were studied. The results indicated that the freezing effects of multi-frequency ultrasound was better than those of single-frequency ultrasound. Multi-frequency ultrasound could significantly increase the freezing rate and preserve the quality of frozen samples better. With increase in the number of ultrasonic frequencies, the freezing effect was more obvious. In addition, scan electron microscopy (SEM) images showed that the ice crystals formed by the multi-frequency ultrasonic treatment were fine and uniformly distributed, which caused less damage to the frozen potato samples. From the analysis of the quality attributes, the nutritional values of the samples after multi-frequency ultrasonic treatment was higher, but attention should be paid to the negative influence of the hydroxyl radical generated by the multi-frequency ultrasound. [ABSTRACT FROM AUTHOR]

• Novel fluidized bed drying methods saved seaweed drying time significantly. • Airborne ultrasound assisted drying method retained highest total phenolic content. • Page model was the best fitting ultrasound assisted fluidized bed drying kinetics. • Seaweed drying after pretreatments saved more energy. In this study, ultrasound either as a pretreatment technique or as an integrated technique was employed to enhance fluidized bed drying of Ascophyllum nodosum , and drying kinetics and dried product quality were assessed. In order to compare technology efficiency and dried product qualities, oven drying and fluidized bed drying (FBD) were employed. The novel drying methods included airborne ultrasound-assisted fluidized bed drying (AUA), ultrasound pre-treatment followed by FBD (USP), and hot water blanching pre-treatment followed byFBD (HWB). Six drying kinetics models were used to describe the drying curves, among which the Page model was the best in fitting USP and AUA. Model by Millidi et al. was employed to describe HWB. Airborne ultrasound in AUA did not reduce energy consumption or drying time, but retained total phenolic content (TPC) as well as colour, and exhibited the highest yield among the novel drying methods. USP and HWB showed lower energy consumption and drying time considerably, but the TPC was the lowest among the studied methods. At the same time, USP dried product exhibited the lowest a w , followed by HWB and then AUA. This studyalso demonstrated that FBD could be a very practical drying method on Irish brown seaweed, and ultrasound-assisted drying methods may have potential developments in Irish brown seaweed drying process. [ABSTRACT FROM AUTHOR]

• Degassing followed by ultrasound-assisted freezing (D-UF) is developed. • D-UF can improve freezing rate and quality of frozen porous foods. • Tissue air volume positively correlates with phase transition time. • Multivariate data analyses can visualize the quality variation of frozen radishes. • D-UF treated radishes have more integrated microstructure. The rapid freezing technique for porous foods using tissue pre-degassing followed by ultrasound-assisted freezing (UF) was developed, and its effects on quality attributes of radishes including tissue air volume, hardness, total calcium contents, bonded calcium contents, retention rates of bonded calcium and microstructures were investigated. To evaluate the freezing efficiency, parameters including total freezing time, phase transition time, and the increases of freezing rate and phase transition rate were determined. Besides, multivariate statistical analyses including principal component analysis (PCA) and hierarchical cluster analysis (HCA) were performed to visualize and further analyze the quality differences of radishes under different treatments. Results suggested that decreasing tissue air volumes can significantly shorten the phase transition time of UF. Samples treated by pre-degassing for 5 min at −0.09 MPa followed by UF (D - 0.09 M P a 5 m i n -UF) showed the freezing rate and phase transition rate increased by 28.8% and 29.8%, respectively, as compared with the same pre-degassed samples frozen by immersion freezing (D - 0.09 M P a 5 m i n -IF). Retention rates of bonded calcium positively correlated with the sample hardness, announcing the importance of bonded calcium maintenance during radish freezing. Both PCA and HCA indicated that D - 0.09 M P a 5 m i n -UF endowed radishes with quality attributes more similar to the fresh ones, which was further verified by microstructure analysis, showing remarkably alleviated plasma membrane puncture, cell separation and deformation in D - 0.09 M P a 5 m i n -UF samples. The current study proved that the technique of tissue pre-degassing followed by UF could effectively improve the freezing efficiency and quality attributes of frozen radishes, and thus have great potentials in rapid freezing of porous foods. [ABSTRACT FROM AUTHOR]