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Alicyclobacillus acidoterrestris (AAT) is a spore-forming bacterium that can survive thermal pasteurization and acidic conditions. Ultraviolet light emitting diode (UVLED) has received extensive attention as a new technology to replace traditional mercury lamps for fruit juice decontamination, however, very few studies on fruit juice have been reported to investigate the sporicidal effect of UVLED on A. acidoterrestris. This research investigated for the first time the application of UVLEDs at 254 nm for the treatment of AAT in tomato juice. The optimized conditions for UVLED, achieved with the aid of Box Behnken design, were 6 cm, 12 min, and 250 mL/min. The results showed that the AAT spores in citrate buffer solution and tomato juice were inactivated by 3-log reduction with a required fluence of 53.67 mJ/cm2. Additionally, UVLED induced an exclusively cellular damage through direct absorption of UV light and direct DNA damage, and indirectly via reactive oxygen species. Besides, the deactivation of AAT spores, validated by LF-NMR analysis, indicated that the free water in AAT might be due to the rehydration of the spore core by the process of germination and then dehydration. This dehydration was further confirmed by the shrinking of spores observed through SEM and AFM imaging. These outcomes were also correlated with those of potassium ions and DPA leakage. This study emphasizes the energy-saving and resistance-reducing features of UVLED in effectively inactivating AAT. • UVLED treatments was divided into multiple closed cycles in Dean flow system. • UVLED achieved a reduction of 3 log CFU/mL in AAT spores in tomato juice. • Potassium release explained a loss of intracellular compounds by cell damage. • DPA photosensitized spores and increased its photoproducts After UVLED. • LF-NMR revealed the rehydration of the spore core by germination. [ABSTRACT FROM AUTHOR]

The majority of acidic fruits are perishable owing to their high-water activity, which promotes microbial activity, thus exhibiting metabolic functions that cause spoilage. Along with sanitary practices, several treatments are used during processing and/or storage to inhibit the development of undesirable bacteria. To overcome the challenges caused by mild heat treatment, juice manufacturers have recently increased their involvement in developing novel non-thermal processing procedures. Ultrasonication alone or in combination with other hurdle technologies may be used to pasteurize processed fruit juices. Multifrequency ultrasound has gained popularity due to the fact that mono-frequency ultrasound has less impact on bacterial inactivation and bioactive compound enhancement of fruit juice. Here, we present and discuss the fundamental information and technological knowledge of how spoilage bacteria, specifically Alicyclobacillus acidoterrestris, assemble resistant spores and inactivate and germinate dormant spores in response to nutrient germinants and physical treatments such as heat and ultrasound. To the authors' knowledge, no prior review of ultrasonic inactivation and germination of A. acidoterrestris in fruit juice exists. Therefore, this article aims to provide a review of previously published research on the inactivation and germination of A. acidoterrestris in fruit juice by ultrasound and heat. [ABSTRACT FROM AUTHOR]

Previous studies on the application of a novel multifrequency ultrasound washing treatment have proven to be effective in guaranteeing microbial safety, and enhancing the quality of cherry tomato. Nevertheless, there is still a need to evaluate the effect of these treatments on the metabolic activity, volatile profile, and sensorial quality of the fruit. This study evaluated the above parameters of cherry tomato treated with optimized assisted and un-assisted multifrequency ultrasound. The treatments slightly enhanced the enzyme activities and inhibit ethylene production and respiration rate. The results indicated that the treatment with 20/40 kHz and aqueous ozone (0.85 ± 0.2 mg/L) for 10 min enhanced and maintained the volatile compounds (VC). Out of the 44 identified VC, one had odor activity value > 1 and thereby considered as active aroma compound contributing significantly to the aroma of the sample. E-nose analysis indicated that alcohol, terpenes, and some aromatic compounds are the core indicators of the significant sensors. PCA showed that the processing methods had an influence on the flavor indexes of the tomatoes. The result verified that all the washing techniques did not result in a substantial negative effect on the tomato, and the treatment with ultrasound and ozone proved to be the best. • Application of various ultrasound washing treatment was investigated. • The treatments slightly enhanced the enzymes activities. • It inhibit ethylene production and respiration rate. • The treatment with ultrasound and aqueous ozone proved to be the best. [ABSTRACT FROM AUTHOR]

Refrigeration is an effective means of reducing losses in fresh fruit; however, its efficacy as a means of preservation is mostly limited to crops that are not vulnerable to chill injury. Cherry tomato is one of these crops where other supporting processes or storage alternatives are sought. The effect of 10-min post-harvest treatment of cherry tomato with individual or combined application of dual-frequency ultrasound (20/40 kHz) and chemical sanitizers was investigated. The sanitizers used are 200 mg/L sodium dichloroisocyanurate (SD), 40 mg/L peracetic acid (PAA), 40 mg/L peracetic acid with 5% H 2 O 2 (PAAH), and 5% hydrogen peroxide. The results showed that the treatments significantly reduced the natural microbiota (aerobic mesophiles and yeasts and molds) within the values of 0.29–3.10 log CFU/g. The highest inactivation was observed for the PAAH and ultrasound when applied as an individual (2.08–2.32 log CFU/g) and combined (3.07–3.10 log CFU/g) treatment. Also, the ultrasound and combined treatment resulted in higher retention of the total phenolic, and flavonoid contents, but with a loss in firmness of the cherry tomato. Nevertheless, during storage, the treatments when compared with the untreated samples, impede the loss in firmness. The other quality parameters such as pH, total soluble solids, titratable acidity, and maturity index were not affected, which signified that irrespective of the treatment, similar changes take place on the fruit during storage, especially in both control and chemically treated fruit. The combination of 40 mg/L PAAH and 20/40 kHz for 10 min caused ≥3-log CFU/g reduction of the natural microbiota. It mitigated the senescence of the cherry tomato during the refrigerated storage (4 °C), which thereby increased the shelf-life. The results obtained at the end of the storage thereby indicated that the combined treatments could guarantee microbial safety and retain the quality of the cherry tomato. • Higher inactivation of microorganisms around 2.12-3.10 log CFU/g was obtained with combined ultrasound and sanitzers • Peracetic acid (40 mg/L) and 20/40 kHz caused ≥ 3-log CFU/g reduction in the natural microbiota. • The combined applications mitigated the senescence of the cherry tomato. [ABSTRACT FROM AUTHOR]

Cherry tomato fruits were treated with three dual‐frequency ultrasound (US) at different temperature and time. The three treatment variables, that is, dual‐frequency US, temperature, and time were optimized with the aid of response surface methodology (RSM). About 20/40 kHz, 52°C, and 6 min were the optimum condition obtained for total bacteria count (TBC, 1.08 log cfu/g), firmness (15.90 N), and total phenolic content (TPC, 34.34 mg GAE/100 g). All the linear relations of the treatment variables showed a significantly negative and positive effect on the TBC and TPC, respectively, while positive significant effects were obtained for some of the relations of the firmness. Hence dual‐frequency sonication is effective for microbial safety and maintaining the quality of cherry tomato. Also, RSM was found to be a useful tool in setting and optimizing the variables responsible for sonication treatment. Practical applications: Thermosonication (ultrasonication and heat) has been applied toward improving the microbial safety and nutritional quality of vegetables and fruit. However, factors such as power, frequency, time, temperature, etc. determine the efficiency of its operation. Controlling these factors is difficult and therefore requires a robust and efficient optimization tool in determining their effects (individual and interactions) on food during treatment. In this study, response surface methodology provides the solution in settling and optimizing the variables for the sonication treatment. Besides, the remarkable result obtained in this work offers an alternative to the combined use of ultrasound and chemical in food industries. [ABSTRACT FROM AUTHOR]

The productiveness of ultrasound (US) is affected by its frequency, power, and time, which has been reported to be very effective during food treatment when combined with other techniques of treatments. The study was aimed to evaluate the effect of mono‐frequency (MFU), simultaneous dual‐frequency (SDFU), and simultaneous tri‐frequency US (STFU) at treatment times of 5–25 min on microbial inactivation and nutritional quality of cherry tomato. Results revealed that within 10 min of sonication, SDFU was most effective compared with MFU toward inhibiting the spoilage microorganisms, delaying ripening as well as maintaining firmness, total phenolic, flavonoid, and antioxidant of the fruit during 21 days of storage at 4°C. Although STFU caused a higher reduction in microbial load after treatment, it, however, showed several adverse effects on the fruit during storage. Overall, SDFU treatment had great potential in preserving shelf life and nutritional value of cherry tomato during storage. Practical applications: US treatment has been implemented toward improving the shelf life of fruit and vegetables. However, a high desirable result has been related to its combination with other physical or chemical methods. The remarkable inactivation of microorganisms obtained for the dual‐ and tri‐frequency treatments under this study would contribute to the application of a nonthermal technique in the reduction of contaminants on ready‐to‐eat fresh products including cherry tomato. Furthermore, the positive effect of this treatment on the quality of the cherry tomato during storage indicated that this technique could be used to replace the common practice of combining US with chemical treatment in food preservation industries. Nevertheless, further exploration is needed toward determining the synergistic effect of these treatments with heat (thermosonication). [ABSTRACT FROM AUTHOR]

Peeling is a crucial part of the tomato deep processing procedure, and the choice of peeling method directly affects the quality of peeling. As far as the conventional peeling methods are concerned, They are still energy and water-intensive and have adverse effects on the environment. The conventional peeling methods often used in the field of tomato peeling were reviewed in this article, including manual, mechanical, chemical, or steam, and the current novel peeling methods, such as enzymatic peeling, pulse electric field peeling, infrared peeling, high-humidity hot air impingement blanching peeling, ohmic heating-assisted lye peeling, flame-catalytic infrared peeling, ultrasonic-assisted lye peeling and CO2 laser-assisted lye peeling. The mechanism, advantages and disadvantages, and applications, of different peeling methods are also summarized and analyzed. In contrast, the novel peeling method excelled in reducing the use of lye and improving the quality of peeled tomatoes. The retention of nutrients such as lycopene, ascorbic acid, and total phenols is extremely dependent on the high texture retention and low peeling loss of peeled pulp. Therefore, the mechanism of peeling and texture preservation after peeling are current research hotspots in the industry. In addition further research should accelerate the scale-up and commercial applicability of the new technology. [ABSTRACT FROM AUTHOR]

Converting biomass to produce renewable chemicals is one of the significant ways to realize the development of green chemistry and sustainable chemical industry. As the main component of lignocellulosic biomass, lignin is the most abundant natural polyphenol. Its unique phenolic properties and high carbon content make it potentially exploited. Biomass lignin depolymerization can be divided into thermochemical, chemical catalysis, electrocatalysis, and biological depolymerization methods. In this review, the catalytic reaction systems involved in different methods of lignin depolymerization were extensively described from various aspects, and the degradation products and reaction mechanisms were discussed and analyzed. The effects of novel green-deep eutectic solvents on biomass lignin depolymerization were reviewed in particular. Each method of biomass lignin depolymerization has its own advantages and disadvantages. The different sources of biomass lignin should be selected objectively according to its compositional structure, so as to achieve efficient biomass lignin depolymerization. In addition, the challenges and future development prospects of biomass lignin depolymerization were also discussed. [ABSTRACT FROM AUTHOR]

A low-cost and green biorefinery will increase the economy and revenue from lignocellulosic biomass. This study demonstrated the effect of two-pot sequential pretreatment, comprising of ultrasound ethanol (USEL) synergized ternary deep eutectic solvent (TDES, choline chloride: glycerol: FeCl 3 ·6H 2 O), with the aim to investigate the effects of USEL, TDES, and USEL + TDES pretreatments on enhancing delignification of sugarcane bagasse (SCB). The results showed that under the optimum TDES pretreatment conditions (FeCl 3 ·6H 2 O, 120 °C, 3 h), the cellulose content and lignin removal rate (LRR) of SCB reached 47.67 and 82.71%, respectively. Under the optimum synergy conditions (USEL conditions: 100% ethanol, 20 + 28 + 40 kHz, 240 W, 60 min; TDES conditions: FeCl 3 ·6H 2 O, 120 °C, 3 h), the cellulose content and LRR of SCB reached 66.17 and 86.39%, respectively. After enzymatic hydrolysis, the SCB pretreated with USEL + TDES shows a saccharification rate of 90.31%, which was substantially higher than that of the SCB pretreated with TDES alone (85.68%). X-ray diffraction, particle size, brunauer-emmet-teller, scanning electron microscopy, and optical microscopy analyses were conducted to confirm the efficiency of USEL + TDES on pretreating SCB. Meanwhile, 2D-HSQC NMR analysis revealed that regenerated lignin exhibited well-preserved structures (β- O -4, β-β linkages), making it suitable for depolymerization into monoaromatic compounds. Overall, this work demonstrated that biomass pretreatment with the USEL + TDES was promising for a low-cost biorefinery to efficiently fractionate lignocellulosic biomass into glucose and high-quality lignin with tailored chemical structures. [Display omitted] • USEL + TDES pretreatment can effectively remove lignin of sugarcane bagasse (SCB). • Conditions:100% ethanol, 20 + 28 + 40 kHz, 240 W, 60 min, FeCl 3 ·6H 2 O, 120 °C, 3 h. • Under the optimal pretreatment, the removal rate of SCB lignin reached 86.39%. • After USEL + TDES pretreatment, enzymatic hydrolysis of SCB yielded 90.31% glucose. • Most of the β- O -4 linkages of the lignin separated by USEL + TDES are cleaved. [ABSTRACT FROM AUTHOR]

• A. acidoterrestris in orange juice (OJ) was inactivated with thermosonication. • Noticeable changes were observed from the 12th day of storage for the OJ quality. • Kinetic behavior of most of the OJ qualities fitted well with non-linear models. • Discrimination between treated and control samples was achieved using E-nose. • Thermosnication extended the shelf-life of the quality quartet of natural OJ at 4 °C. The effects of moderate thermosonication (MTS) on the quality quartet: physico-chemical, microbial, nutritional and sensory qualities of orange juice (OJ) inoculated with Alicyclobacillus acidoterrestris (AAT) were studied during 24 days of storage at ambient and refrigerated temperatures. The bioactive compounds and antioxidant activity of OJ decreased with storage, while the pectin methyl esterase (PME) increased. Nonetheless, noticeable changes were observed from the 12th day of storage. There was no obvious (p > 0.05) variation in pH and total soluble solids. To determine the nutritional and microbial quality characteristics of OJ during storage, non-linear kinetic curves were successfully fitted with least square fitting polynomial and four-parameter log-logistic distribution models. The E-nose sensors succeeded in discriminating between the aroma of non-treated and treated OJ based on linear discriminant analysis (LDA). Furthermore, terpenes, alcohol and partially aromatic compounds were the main spoilage indicators of OJ during storage based on E-nose analysis and confirmed by HS-SPME-GC/MS analysis. Thus, MTS significantly extended the shelf life of the quality quartet of natural OJ at 4 °C. E-nose-GC/MS fusion offered odor fingerprints to AAT microorganisms that can be used as spoilage index without using traditional food analysis techniques. The proposed approach can be used as an alternative tool for rapid detection of spoilage microorganisms in OJ. [ABSTRACT FROM AUTHOR]

The research work investigates the effect of different pretreatment conditions (osmotic dehydration [OD], ultrasound [US], and ultrasound‐assisted osmotic dehydration [UOD]) on the drying kinetics modeling, thermodynamics, weight reduction, degradation kinetics of vitamin C, and color of apple slices under pulsed vacuum dryer (PVD). The findings showed that UOD pretreatment significantly improved drying time and increased weight reduction comparative to OD, US, and the control sample. Drying kinetics modeling revealed that the Hii model better described the drying kinetic behavior of the apple slices than the other nine mathematical models based on higher coefficient of determination (R2), root mean square error (RMSE), and reduced chi‐square (χ2). Analysis of vitamin C content revealed a 46.05%, 31.28%, and 25.95% retention for UOD, US, and OD, respectively, after drying. Second‐order kinetics could accurately predict the degradation kinetics of vitamin C compared to first‐order kinetics. Vitamin C degradation kinetics showed lower k‐value, higher D‐value (time required for 90% degradation), and half‐life indicating a higher retention of vitamin C content for UOD pretreatment compared to OD and US during drying. L*, b*, and chroma values of UOD were significantly (P < 0.05) higher compared to US, OD, and the control sample. Practical Application: The findings of this study revealed that ultrasonic‐aided osmotic dehydration is a unique and novel pretreatment technique prior to drying, which significantly shortens drying time as a result of faster moisture/mass transfer, improves processing efficiency thereby reducing processing cost, improves quality parameters, and preserve phytochemicals. This makes the business operations of food processors competitive and as well provide value for customers. [ABSTRACT FROM AUTHOR]

Abstract With the aim of finding an alternative ameliorative mechanism for 2-furoylmethyl-amino acid (2-FM-AA) formation in drying technology, this work was conducted. This was achieved by drying banana with relative humidity (RH) convective hot-air dryer at 60, 70 and 80 °C under RH (10% 20% and 30%) at 2.0 m/s air velocity. The results revealed that at every 10% increase in RH, a reduction between 13.4 and 29.4% of the 2-FM-AA was achieved. Based on statistical parameters such as coefficient of correlation (0.9104–0.9998), root mean square error (0.0176–0.3620) and reduced chi-square (1.5 × 10-4–0.1310), the first order model could satisfactorily predict 2-FM-AA formation. Furthermore, rate constants revealed the dependence of 2-FM-AA formation on RH and also demonstrated the critical role played by RH in reducing 2-FM-AA formation. The results also show that, higher temperatures were mainly responsible for 2-FM-AA formation and functional groups deformation; however this can be mitigated when drying is conducted under higher RH. Highlights • Ameliorative mechanisms using RH for 2-FM-AA formation was determined. • Between 13.4 and 29.4% reduction of 2-FM-AA was achieved by 10% increase in RH. • First order model could satisfactorily predict 2-FM-AA formation. • Change in color was potentiated by lower RH in all drying temperatures. • RH played critical role in determining the chemical changes in functional groups. [ABSTRACT FROM AUTHOR]

[Display omitted] • DFTS induced A. acidoterrestris spore germination in orange juice. • Conductivity confirmed spore inner membrane (IM) damage by DFTS before germination. • Low DPA concentrations were achieved after 10 h incubation with L-alanine (L-ala). • TEM displayed IM poration and coat detachment of spore before L-ala germination. The off-odors associated with spoilage of acidic beverages are linked to the germination and growth of Alicyclobacillus acidoterrestris (AAT) spores. As a consequence, we determined the influence of nutrients, non-nutrient germinants, dual-frequency thermosonication (DFTS), and food matrix on spore germination. AAT spores in orange juice (OJ), supplemented by L-alanine (L-ala), had the highest germination rate and lowest DPA content at 10 h of incubation. The formation of microscopic pores in cell membranes during DFTS caused irreversible damage in AAT spores in citrate buffer solution (CBS); however, it stimulated AAT spore germination in CBS containing L-ala. Hence, the germination potential was established in the order: L-ala > Calcium dipicolinate > asparagine, glucose, fructose, and potassium ion mixture (AGFK) > L-valine. The conductivity analysis indicated that membrane damage could be a key factor contributing to the artificial germination in CBS. AFM images revealed that after 2 h of adding L-ala, the protein content increased with increased germinated cells. TEM showed that membrane poration and coat detachment were the main pre-germination morphological changes detected after DFTS treatment. This study provides evidence that germination stimulated with DFTS might be an effective strategy for reducing A. acidoterrestris spores in fruit juices. [ABSTRACT FROM AUTHOR]

• Ultrasound-assisted treatment at mild heat extended shelf life from 3 to 12 d. • Combined treat inhibited microorganism and the activity of PAL, PPO and POD. • Combined treat affected cell structural integrity of lotus root. Ultrasound-assisted probiotic fermentation suspension treatment under mild heat was applied to freshly cut lotus root. Combined treatment significantly (p < 0.05) improved the bactericidal effect: S. aureus , E. coli O157:H7, A. flavus spores, and yeast were completely killed at 55℃ for 6 min, morphological and structural changes of cells were observed. Combined treatment inhibited enzymatic browning via decreasing the activities of PPO, POD, PAL, and decreasing TPC, soluble quinone content. The decrease of external resistance, capacitance and the increase of internal resistance reflected the loss of structural integrity of cells after combined treatment. For combined treatment samples, no obvious color change was observed during 12 days of storage but weight loss rate, total acid increased significantly (p < 0.05) and hardness decreased, the shelf life was extended to 12 d. Ultrasound-assisted probiotic fermentation suspension treatment under mild heat had the dual effects of sterilization and inhibition of browning. [ABSTRACT FROM AUTHOR]

[Display omitted] • A.acidoterrestris (AAT) was inactivated by 5 logs via cell sonoporation. • Double-frequency ultrasound (DFUS) waves induced ROS and caused DNA damage. • Microstructure analysis showed that DFTS had a greater bactericidal effectiveness. • FTIR detected modifications in AAT proteins, nucleic acids and lipids, induced by ROS. Alicyclobacillus acidoterrestris (AAT) was proposed as an index of pasteurization design for high-acid fruit products due to its spore resistance and repeated spoilage incidences in fruit juices. This study aimed to determine the effectiveness of pulsed multifrequency ultrasound to minimize AAT spores and vegetative cells in aqueous suspension. For this research, an investigation of the reactive oxygen species and antioxidant activity was performed to examine the effect of temperature and frequency on AAT spore inoculation. Total decreases in AAT bacteria were 5.99, 5.74 Log CFU/mL in vegetative cells for dual-frequency thermosonication (DFTS) and dual-frequency ultrasonication (DFUS), respectively, while 5.90 and 5.38 Log CFU/mL in spores for both DFUS and DFTS, respectively. The loss of the percentage of cells in ultrasound (US) and thermosonication (TS) treatments was inversely associated with the rate of O 2 −and H 2 O 2 development. The fluorescence microscopy revealed a higher bactericidal efficacy of DFTS compared to the DFUS and control. Scanning Electron Microscopy (SEM) and Transmission electron microscopy (TEM) demonstrated ultra-structural modifications such as the interruption of cell walls by cavitation and pores in the membrane structure of the AAT bacteria induced by sonoporation. Several TS frequencies of 20/40/60, 20/40, and 20 kHz treated spores had a higher electrical conductivity than untreated ones, with an improvement of 7.94, 5.68, and 3.72 %, respectively. Fourier-transform infrared (FTIR) spectroscopy revealed major changes in the spectral region of membrane fatty acids and proteins of AAT. Simultaneously, AAT inactivation specific energy rate was significantly reduced using dual-frequency ultrasound, compared to mono-frequency thermosonication. The significant results of this work recommended pulsed DFUS as an alternative application to mono-frequency US in beverage industries. [ABSTRACT FROM AUTHOR]

Catalytic infrared (CIR) technology for sterilization has not been widely applied owing to the lack of comprehensive and in-depth mechanistic research. This study aims to explore further the inactivation mechanism of CIR against Pseudomonas aeruginosa in green Sichuan pepper (GSP). First, the working pattern of the CIR was investigated using a colony counting method in different layouts. The results indicated that the bacteriostatic effect on GSP was weaker than that on plates with low-dose CIR radiation, and both the surrounding air and surface moisture content affected the sterilization rate of P. aeruginosa. Second, the bacteriostatic mechanism of CIR against P. aeruginosa was investigated. The results indicated that the bacteriostatic effect of CIR could be mainly caused by the destruction of the cell membrane, inhibition of swimming motility, and membrane dysfunction simultaneously, and it was also caused by weaker DNA breakage compared with pulse strong light. Finally, the flavour influence of CIR in GSP was determined in terms of volatile oil content, aroma component, alkaloid content, and colour change. After 0–4 min of CIR treatment, the changes in the flavour of GSP were all within the acceptable range. Consequently, CIR technology is a promising approach for effective decontamination of the GSP surface, which works mainly on cell cover and can weakly penetrate the cell membrane. [Display omitted] • Working pattern of CIR on decontamination of green Sichuan pepper was redefined. • Anti-bacterial mechanism of CIR on sub-cellular level was investigated. • Damage degree of bacterial DNA was investigated by RAPD-PCR. • Dynamic display of bacterial swimming motility during CIR treatment was established. [ABSTRACT FROM AUTHOR]

The primary aim of this study is to investigate the impact of intensive pulsed light (IPL) on the activity, structure, and physico-chemical properties of polyphenol oxidase. The results showed that the lower the concentration of PPO, the lower the intensity and fluence required inactivating 90% of PPO. With the increase of the IPL fluence, the content of ɑ-helix and β-turn decreased by 57.6% and 22.5%, and the content of β-fold and random curl increased by 58.2% and 69.0%, respectively. The endogenous fluorescence intensity decreases, which proves that IPL effectively inactivates PPO by destroying the secondary and tertiary structure of PPO. Surface hydrophobicity, free sulfhydryl content, aggregation index, and turbidity increased by 191.0%, 24.3%, 23.5%, 151.7%, respectively. The atomic force microscopy (AFM) results showed that the height distribution increased from 3 to 8 nm to 12–16 nm as the fluence increased, and the surface roughness decreased. This research provides a theoretical basis for applying IPL technology in inhibiting endogenous enzyme activity in food and controlling the browning of fruits and vegetables. [Display omitted] • IPL could rapidly inactivate polyphenol oxidase. • IPL could change the secondary and tertiary structure of polyphenol oxidase. • IPL led PPO aggregation and deformation. • IPL could expose the hydrophobic groups of proteins and enhance hydrophobicity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The HHV and exergy of pretreated watermelon rind (WMR) biomass were evaluated. • Co-pyrolysis of the WMR biomass and coal blends were studied. • Four isoconversional methods were employed to determine the kinetic parameters. • Activation energy & enthalpy varied directly with the amount of coal in the blends. • Among the models, Friedman method was the best predictor of the kinetic parameters. The higher heating value (HHV) and exergy of ultrasound-assisted deep eutectic solvent pretreated watermelon rind (WMR) biomass were investigated. Thereafter, the co-pyrolysis of the WMR biomass and coal blends was studied. The pyrolysis kinetics and thermodynamic parameters of the WMR-coal blends were determined using four isoconversional models (Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, Friedman and Starink). The HHVs of the pretreated WMR ranged between 12.73 and 19.28 MJ / k g , while the exergy value for the raw and pretreated WMR were 16.08 and 21.55 MJ / k g , respectively. The lower heating value related exergy had the greatest influence on the overall exergy of the WMR. The values of the pre-exponential factor showed variations in wide range, and the change in entropy of the system displayed both negative and positive entropies. The activation energy and enthalpy varied directly with the amount of coal in the blends. Amongst the isoconversional model methods, Friedman model was the best predictor of the kinetic parameters. [ABSTRACT FROM AUTHOR]

B cereus was extracted from pork meat and detected using conventional polymerase chain reaction, (PCR). The spores were infected in the pork and the inactivation behavior was scrutinize by thermal (80 °C and 90 °C), sole ultrasonication, US (20 kHz) and thermosonication (TS), at single frequency TSsf (20 kHz, 70 °C) and multi-frequency TSmf (20/40/60 kHz, 70 °C) using a maximum power of 300 W over a period of 25 min. The most convenient and time-saving treatment method of the infected pork were investigated. TSmf proved to be favorable treatment method as it gave a 4.16 log CFU/ml spore reduction within 5 min. The various treatments were modelled to predict the best fit for the study. Weibull model gave the best fitness and the various parameters showed the effectiveness of the treatments as follows: thermal (80 °C) < thermal (90 °C) < US (20 kHz) < TSsf (20 kHz, 70 °C) < TSmf (20/40/60 kHz, 70 °C) for the deactivation of B. cereus spores in pork. Finally, US and TSmf methods enhanced the physicochemical properties (pH, texture and color) of pork. • Conventional PCR was used to identify Bacillus cereus from pork. • Pork infected with B. cereus was subjected to thermal, US and TS inactivation methods. • The efficiency was determined based on kinetic models. • Weibull model was the best fitting model. • Thermosonication enhanced physicochemical qualities of pork. [ABSTRACT FROM AUTHOR]

Sequential delignification of watermelon rind using ultrasonication and deep eutectic solvent (DES) pretreatment methods was demonstrated in this study. The effects of pretreatment factors on delignification were investigated using parametric screening and subsequent optimization of significant factors. Plackett–Burman Design was used for the screening of pretreatment variables, while optimization was performed adopting Central Composite Rotatable Design. For the range of variables considered in the study, the screening experiments revealed that the effects of ultrasonication power, ultrasonication frequency, ultrasonication time, DES reaction temperature and DES reaction time on delignification were significant, while the effects of ultrasonication solid-liquid ratio, ultrasonication temperature, hydrogen bond acceptor/hydrogen bond donor molar ratio, and DES solid-to-liquid ratio were not significant. The significant factors were further investigated and maximum lignin removal of 43.56 % was achieved at ultrasonication power 180 W , ultrasonication frequency 60 k H z , ultrasonication time 40 m i n , reaction temperature 120° C and reaction time 180 m i n. Synergistic effect between the two pretreatment methods was observed and it correlated positively with the severity of the ultrasound pretreatment. The SEM and FTIR analyses further established the effectiveness of the sequential combinative pretreatment methods on watermelon rind delignification. • Novel two-pot approach ultrasound-assisted DES pretreatment was demonstrated. • Effect of pretreatment factors on watermelon rind delignification was investigated. • Synergistic effect between ultrasonication and DES pretreatments was observed. • Synergistic effect correlated positively with severity of ultrasound pretreatment. • SEM and FTIR established the effectiveness of the combinative pretreatment methods. [ABSTRACT FROM AUTHOR]

Thermosonication (TS) was applied to optimize the quality characteristics of orange juice and to inactivate Alicyclobacillus acidoterrestris vegetative cells using the Box–Behnken design by varying temperature (45–75°C), time (20–40 min), and frequency (20–60 kHz). Results from the response surface methodology showed that the optimal conditions for TS were 47°C, 30 min, and 20 kHz. The models generated were highly significant (p < .001) with the coefficient of determination of 0.986–0.996. The optimal conditions demonstrated high total phenolic contents (TPC) (490.85 mg GAE/100 ml), pectin methylesterase (PME) enzyme inactivation (94.77%) as well as low A. acidoterrestris vegetative cells' load (1.00 log reduction). In addition, total flavonoids contents (38.50 mg/100 ml ER), ascorbic acid (441.70 mg/ml), color change ΔE (1.85), polyphenol oxidase enzyme (56%), and antioxidant capacity (FRAP, 107.33 g/100 ml AEAC, DPPH, 85.90%) of treated orange juice showed a significant (p < .05) difference compared to the control. Thus, TS significantly enhanced the quality of the natural orange juice. Practical applications: The negative impact of Alicyclobacillus acidoterrestris is a major concern for the food industry. Reducing their amount in food by thermosonication is gaining much attention lately. This kind of green technology represents a quick, efficient, and economical substitute to improve the quality of fruit juices. [ABSTRACT FROM AUTHOR]

The effect of ultrasound (US), osmotic dehydration (OD), and osmosonication (OS) pretreatments on total phenolic content (TPC), total flavonoids content, (TFC), phytochemical constituents (gingerol derivatives and diarylheptanoids), polyphenol oxidase (PPO), peroxidase (POD), 2,2‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS), cupric ion reducing capacity (CUPRAC), 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), ferric reducing antioxidant power capacity (FRAP), and color of ginger slices dried under relative humidity convective dryer was investigated. OS pretreatment improved the preservation of TPC (13.80–34.79 mg GAE/g d.w), TFC (26.46–62.16 mg CE/g d.w), ABTS (30.37%–86.10%), CUPRAC (36.89–73.97 mg/g), DPPH (50.57%–92.60%), FRAP (26.44‐83 mg/g), and phytochemical constituents than US and OD. The OS‐treated sample was more effective in inactivating both PPO (12.09%–35.93%) and POD (16.21%–39.58%) enzymes compared to US and OD‐treated samples. However, US pretreatment retained the color quality of dried ginger slices than the OS and OD treatments. OS pretreatment (5.43) also increased the total color change (ΔE) of the dried ginger samples compared to US (2.81) and OD (4.60). Practical applications: Ginger is commonly used in the food, beverage, and pharmaceutical industries owing to their distinctive flavor and various health potentials. However, its high moisture content makes its inappropriate for long‐term storage which results in its high perishability. Drying is one of the most common techniques to prolong its shelf life. Hence, any pretreatment for ginger that reduces the moistures content and lessens the drying time by preserving the quality of the crop is of vital importance. Ultrasound, osmotic dehydration, and osmosonication are novel pretreatment techniques that are widely used prior to drying of various agricultural products due to its numerous advantages over conventional methods. Its application in drying of foods could help shorten the drying time, reduce processing costs, improve energy consumption and efficiency, and preserve the physical and nutritional properties of the dried product. The current findings will also offer more information for selecting pretreatment techniques for ginger drying. [ABSTRACT FROM AUTHOR]