Search

The utilization of nanomaterials to ensure food safety has been attracting more attention in recent years. The fabrication of nanomaterials is obviously important and also challenging. Conventional nanomaterials fabrication methods including mechanical, hydrothermal, and vapour phase deposition have the disadvantages of high energy consumption, low yield, insufficient control precision, and environmental pollution. Cold plasma as an innovative strategy, comprising ions, electrons, atoms, free radicals, and neutral particles, is very beneficial to fabricate nanomaterials. This review summarizes the principles and progress of cold plasma-fabricated nanomaterials including inorganic nanomaterials, carbon nanomaterials, framework nanomaterials, and biomass nanomaterials. Various applications of cold plasma-fabricated nanomaterials in food safety for antimicrobial, detection and removal of contaminants, and food packaging are also detailly discussed. The advantages, limitations, and prospects of cold plasma-fabricated nanomaterials for food safety applications are pointed out. Cold plasma fabrication is environmentally friendly, producing minimal waste and reducing the need for harsh chemicals, aligning with sustainable practices in the food industry. Cold plasma-fabricated nanomaterials have applications in antimicrobial, detection, and removal of pollutant residues, food packaging, and other food safety applications. Future studies should further explore the methodology, safety evaluation, and application of cold plasma preparation of nanomaterials to promote their practical application in the field of food safety. • The principles and mechanisms of fabricating nanomaterials by cold plasma. • Various applications of cold plasma-fabricated nanomaterials for food safety. • Advantages of fabricating nanomaterials to ensure food safety by cold plasma. • Future challenges of cold plasma-fabricated nanomaterials to ensure food safety. [ABSTRACT FROM AUTHOR]

Critical questions remain regarding the need for intensity to continue NPIs as the public was vaccinated. We evaluated the association of intensity and duration of non-pharmaceutical interventions (NPIs) and vaccines with COVID-19 infection, death, and excess mortality in Europe. Data comes from Our Word in Data. We included 22 European countries from January 20, 2020, to May 30, 2021. The time-varying constrained distribution lag model was used in each country to estimate the impact of different intensities and duration of NPIs on COVID-19 control, considering vaccination coverage. Country-specific effects were pooled through meta-analysis. This study found that high-intensity and long-duration of NPIs showed a positive main effect on reducing infection in the absence of vaccines, especially in the intensity above the 80th percentile and lasted for 7 days (RR = 0.93, 95% CI: 0.89–0.98). However, the adverse effect on excess mortality also increased with the duration and intensity. Specifically, it was associated with an increase of 44.16% (RR = 1.44, 95% CI: 1.27–1.64) in the excess mortality under the strict intervention (the intensity above the 80th percentile and lasted for 21 days). As the vaccine rollouts, the inhibition of the strict intervention on cases growth rate was increased (RR dropped from 0.95 to 0.87). Simultaneously, vaccination also alleviated the negative impact of the strict intervention on excess mortality (RR decreased from 1.44 to 1.25). Besides, maintaining the strict intervention appeared to more reduce the cases, as well as avoids more overall burden of death compared with weak intervention. Our study highlights the importance of continued high-intensity NPIs in low vaccine coverage. Lifting of NPIs in insufficient vaccination coverage may cause increased infections and death burden. Policymakers should coordinate the intensity and duration of NPIs and allocate medical resources reasonably with widespread vaccination. [ABSTRACT FROM AUTHOR]

The effect of plasma functionalized water (PW) pretreatment and influencing factors including treatment time and voltage were investigated on the drying kinetics, nutrition and sensory properties of tomato slices during infrared-accelerated pulsed vacuum drying (IR-PVD). Results revealed that PW pretreatment caused disruptions in tomato cellular structure that were greater with increasing treatment time and voltage, due to strong acidification and etching from reactive species in PW. These disruptions accelerated the removal of moisture during IR-PVD to shorten drying time by 25%, and improve visual appearance, rehydration, porosity, phenols and flavonoids, soluble solids, lycopene, ascorbic acid, but reduced chewiness, gumminess and hardness properties. Overall, the findings revealed the propitious potentials of PW and indicated the significant effects of PW influencing factors for accelerating drying characteristics and increasing the functional and nutrition properties of tomato slices during IR-PVD, providing a theoretical basis for developing novel energy-saving drying approaches. • Plasma water provides a viable alternative for pretreating tomato slices prior to IR-PVD. • Increasing treatment time and voltage led to increased porosity in the microstructure. • Plasma water accelerated moisture transfer and shortened drying time. • Highest vitamin C retention achieved at the peak of treatment time and voltage. • Future studies should emphasis on optimization for large-scale applications. [ABSTRACT FROM AUTHOR]

• MH and RSH treatments significantly increased fat loss of pork subcutaneous back fat. • The size of individual adipocytes increased and then decreased during MH and RSH. • Vesicles were simulated as cell membrane to study the mechanisms of fat changes. • The particle size of the vesicle increased and then decreased during MH and RSH. Fat reduction due to heating or cooking is an important issue in a healthy diet. In the current study, pork subcutaneous back fat was treated via microwave heating (MH) within 10—90 s and roasting - steam heating (RSH) within 2—30 min and their dynamic changes of individual adipocytes were explored by using vesicles as a bio-membrane model. The result showed that MH and RSH significantly increased fat loss (P < 0.05), with the maximum losses being 74.1 % and 65.6 %, respectively. The mechanical strength of connective tissue decreased and then increased slightly. The microstructure demonstrated that MH and RSH treatments facilitated a large outflow of fat, showing that the particle size of the vesicle and individual adipocytes increased and then decreased. It is thus feasible to study the dynamic changes of individual adipocytes in regulating fat reduction using cell membrane simulation. [ABSTRACT FROM AUTHOR]

• Red dragon fruit peel was dried using electromagnetic and convective approaches. • Microwave drying enhanced moisture removal and reduced drying time. • Mid-infrared drying resulted in improved colour of the red dragon fruit peel. • Far-infrared drying enhanced the retention of phenolics, flavonoids and betalains. • Microstructural analysis elucidated the underlying mechanism of quality changes. The effects of near-infrared (NIRD), mid-infrared (MIRD), far-infrared (FIRD), microwave (MWD), and hot air drying (HAD) on drying kinetic, colour, phytochemical composition, and antioxidant activity of red dragon fruit peel (RDFP) was evaluated. Results indicated that drying methods induced varying microstructural and chemical changes on RDFP, significantly influencing moisture removal rates and phytochemical retention. The lowest drying time was observed for MWD, while MIRD presented the highest drying time. FIRD drying was more favourable for retaining TPC, TFC, betacyanin and betaxanthin, while the ascorbic acid content was better retained during MIRD and NIRD. Enhancements in ABTS, CUPRAC and reducing power were associated with FIRD, and NIRD and MIRD enhanced DPPH and HRSA. Overall, chemical modifications induced by drying improved the phytochemical and antioxidant properties but presented adversative effects on ascorbic acid and DPPH. The study presented an essential background for the optimal drying of RDFP. [ABSTRACT FROM AUTHOR]

This study aimed to assess the effects of chitosan on the gelling properties of tilapia surimi gels during microwave (MW) heating treatment from composite gel layer to myofibrillar proteins (MPs) layer. For composite surimi gel, the hardness, elasticity, and water holding capacity of surimi gel with 0.004 % chitosan (CS) initially increased and then reduced with the increasing MW power (0–9 W/g). Rheometer measurements demonstrated that the samples displayed high elasticity across the entire frequency range (0.1–100 Hz) and exhibited gel-like characteristics. The best apparent morphology of surimi gel was observed at MW power of 3 W/g. To further explain the interaction, MPs solutions with different CS volume ratio (0–10 %) showed significant aggregation and more formation of disulfide bonds. Moreover, ultraviolet and intrinsic fluorescence spectra showed that the surimi samples had protein structural characteristics. Furthermore, molecular dynamics (MD) simulations were used to initially investigate and explain the interactions between MPs and CS under the MW treatment, indicating that MPs/CS complex exhibited higher flexibility and a greater tendency to react and transition into a more compact three-dimensional (3D) network structure during the MW treatment. Therefore, this study provides a deeper understanding of the mechanism involved in microwave-assisted tilapia surimi gel formation, thereby expanding industrial applications of surimi products. [Display omitted] • With addition of CS could improve the gelling properties of tilapia surimi. • MW facilitated the MPs/CS complex to form a more stable and compact structure. • The mechanism between MPs and CS under MW heating was revealed by MD simulations. [ABSTRACT FROM AUTHOR]

Fruits and vegetables are an essential class of food with enormous nutritional and commercial gains. With the surge in interest for nutraceuticals, the demand for high-quality fruits and vegetables have gained traction in recent times. In a bid to extend shelf life and retain quality to meet demand, drying of fruits and vegetables has been accompanied by pretreatments. Conventional pretreatments have shown to improve the drying process in terms of drying kinetics and final product quality. However, for further improving and enhancing the drying process, novel nonthermal and thermal pretreatments have been investigated. This paper reviews some novel nonthermal and thermal pretreatment techniques with a focus on their efficacies to improve the drying process in terms of amelioration of drying kinetics and enhancement of the functional and nutritional quality of the dried product. Details of the pretreatment techniques including cold plasma, pulsed electric field, edible coating, ultrasonication, high humidity hot air impingement blanching, infrared blanching, and microwave blanching are discussed, and their possible application drawbacks and prospects in future developments are also presented. Key Findings and Conclusions: The development and application of novel pretreatment techniques can not only shorten drying time, increase drying rate, improve moisture distribution, and lower energy consumption but can also further enhance the functional and nutritional quality attributes of the dried products better than conventionally pretreated and untreated samples. Additionally, combinations of these technologies and adequate modelling approaches for optimizing the pretreatment conditions can further boost their effectiveness in enhancing the drying process. • Pretreatments can enhance drying performance and improve product quality. • Nonthermal techniques can facilitate permeability by tissue modification. • Novel thermal techniques can accelerate moisture evaporation and transfer. • Future work can focus on hurdle technology and process modelling. [ABSTRACT FROM AUTHOR]

Antioxidative metabolome is crucial for Listeria monocytogenes (Lm) to alleviate the instant oxidative stress, resulting in the occurrence of the sub-lethal injured Lm and potential risks to environment and food safety. However, the antioxidative strategies of the metabolome beneath the sub-lethal injured Lm in resisting the instant active species remain unclear. Therefore, under the intrusion of cold plasma (CP) active species, the sub-lethal injured Lm emerged via the wrinkled membranes and the disturbed physiological functions. Antioxidative metabolic strategies in the sub-lethal injured Lm were investigated by multi-omics technology based on the activity of antioxidant enzymes. The current study demonstrated that the antioxidative metabolome (176 differential metabolites) played a pivotal role in combating the instant active species compared with the antioxidative regulation of 15 genes. Furthermore, antioxidative strategies of metabolome were involved in multilayer patterns: one-off consumption, rapid utilization, and up-regulation of (R)-lipoic acid. Hence, lipoic acid metabolism was activated as an emergency pathway. Besides, the iron acquisition was operated and toxic metabolites were effluxed to balance the intracellular homeostasis. In conclusion, this work provides unique insights into the antioxidative metabolic strategies in the sub-lethal injured Lm , offering a basis for the precise inactivation of the sub-lethal injured foodborne pathogens during food processing. • CP stressed Lm into sub-lethal injury by affecting cell membranes negatively. • Sub-lethal injured Lm can survive CP stress by different antioxidative patterns. • Lipoic acid within Lm is used as an emergency aid against instant CP stress. • Sulfur-related antioxidants are encouraged within Lm stressed by CP active species. [ABSTRACT FROM AUTHOR]

Atmospheric pressure dielectric barrier discharge cold plasma (CP) is an effective method for inactivating microorganism contamination. However, improving CP inactivation efficiency as affected by CP reactor parameters still remains unstudied. In this study, the effects of discharge voltage, dielectric material and dielectric thickness of CP reactor on inactivation performance were investigated, and their influence mechanisms on plasma discharge were discussed. Results indicated that efficiency was improved using the reactor parameters of a high discharge voltage (17 kV) with a centre frequency (10 kHz) and a high dielectric constant (ceramic) with a small dielectric thickness (1 mm), resulting in higher electron number density and electric field strength, producing more reactive substances for enhancing microorganism inactivation. Under the above conditions, CP treatment for 4 min inactivated 99.6% of Salmonella typhimurium and 96.1% of Listeria monocytogenes. It is hoped that this work could guide the design of commercial CP systems. • A novel evaluation method was established to assess the performance of reactors. • The plasma characteristics were diagnosed by electrical and optical methods. • The effects of CP reactor parameters on inactivation performance were investigated. • The possible influence mechanism of CP reactor parameters was proposed. [ABSTRACT FROM AUTHOR]

• Effects of CP treatment on TM allergenicity were characterized by a mouse model. • The potential of CP to eliminate the TM allergenicity was verified. • The mechanism of intestine flora-involved allergy occurrence was revealed. • The possibility of CP regulating intestine flora to inhibit allergy was exhibited. In vivo biological regulations of the allergenicity of tropomyosin (TM) treated by cold plasma (CP) were investigated by in vivo mouse model. The sensitization models of Balb/c mice were successfully established. CP treatment reduced the allergic symptoms of mice and regulated the Th1/Th2 balance to prevent allergy by activating Treg cells, which was deduced by serum and cytokines analysis. For intestinal flora analysis, allergy occurrence was accompanied by the decreased species abundance and the increased species diversity of intestinal flora. The significant species composition difference between the TM group and the PBS group showed a possible connection between bacterial diversity and allergy. Furthermore, Firmicutes, Bacteroidetes, Parabacteroides, Alloprevotella, Bacteroides, and Lachnospiraceae could relate to allergy occurrence. Intestinal section analysis suggested that allergy occurrence was accompanied by the damaged intestinal structure, and CP treatment could relieve the damage caused by an allergy. [ABSTRACT FROM AUTHOR]