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Strawberries rich nutrition, flavor, and aroma profiles make them popular. Many studies have tried to extend strawberries shelf life. In the current study, grape pomace extract (GPE) was combined with polyvinyl alcohol (PVA) and used to extend the shelf life of strawberries. Ascorbic acid content, total phenolic content, total anthocyanin content, and antioxidant activity determinations showed that PVA/GPE-coated strawberries were superior to the uncoated fruits during storage. Total mesophilic aerobic bacteria (TMAB) and yeast/mold counts in the uncoated strawberries were 2 and 2.68 log cfu/g at the start of storage, respectively, and 9.8 and 14.00 log cfu/g after 16 days of storage, respectively. Strawberries coated with the PVA solution with 2.5% (w/v) GPE showed 32% and 25% less TMAB and yeast/mold counts, respectively, at the end of storage. The PVA/GPE-coated strawberries showed significantly higher firmness compared to the control fruit. The PVA/GPE coating improved strawberry shelf life and functional properties. [ABSTRACT FROM AUTHOR]

This research presents the effect of combining UV‐C irradiation and vacuum sealing on the shelf life of strawberries and quartered tomatoes and compares it with the effect of the sole use of UV‐C irradiation or vacuum sealing. A constant UV‐C dose of 360 J/m2 was used for the samples' irradiation, and all the vacuum‐sealed samples were stored at a reduced pressure of 40 kPa. Organoleptic analysis, microbial population quantification of yeast and mold, Pseudomonas sp., weight loss, and pH measurements were obtained to identify the spoilage occurrence, monitor the samples' quality, and quantify the shelf life. Sensory evaluation was conducted by 12 consumer panelists to evaluate the aroma, taste, color, texture, and the overall acceptance of the samples. The results revealed that the combination of UV‐C irradiation and vacuum sealing prolongs the shelf life of perishables more than the sole use of UV‐C irradiation or vacuum sealing. The achieved shelf‐life increase using this combination was 124.41% and 54.41% for strawberries and quartered tomatoes, respectively, while acceptable sensory characteristics were maintained throughout the storage period. Hence, this food preservation method can be further improved and integrated in the daily life of modern consumers and the operations of fresh produce retailers, as it could effectively reduce the spoilage rates of fresh produce and help achieve the UN SDG 12.3, which aims to reduce food loss and waste by 50% by 2030 at the consumer and retail levels. Practical Application: The system can be further developed and introduced to the market as a kitchen appliance for households or as a predistribution step for fresh produce distribution centers. The shelf‐life extension capability of this system, which does not involve any use of chemical substances, would make it an attractive solution for households and food retailers. [ABSTRACT FROM AUTHOR]

[Display omitted] • CNF-based packaging film was synergistically reinforced by lignin and tea polyphenols. • The composite film exhibited excellent mechanical and barrier performances. • The composite film possessed remarkable antibacterial and antioxidant properties. • The composite film could significantly extend the shelf life of strawberry. Developing biomass-based food packaging materials could alleviate resource scarcity and environmental pollution. This study successfully fabricated cellulose nanofibrils-based packaging films synergistically reinforced by lignin and tea polyphenols for fruit preservation. Thanks to the abundant carboxyl and hydroxyl groups in modified lignin and tea polyphenol, the composite film delivered the highest tensile strength and Young's modulus of 230.7 MPa and 11.9 GPa, respectively. The water vapor permeability (WVP) and oxygen permeability (OP) of composite film were as low as 2.53 × 10−11 g m−1 s−1 Pa−1 and 1.69 × 10−16 cm m−2 s−1 Pa−1, respectively, demonstrating excellent barrier performance. Furthermore, the composite film possessed remarkable antibacterial (100 % antibacterial activity against two types of bacteria), antioxidant (DPPH free radical scavenging activity of 90 %), and UV shielding properties (impressive UV shielding rate of 99.0 %). Strawberry preservation experiments showed that these composite films could significantly extend shelf life, owing to the excellent barrier and antimicrobial properties. Our research indicated that these composite films could be promising food packaging material compared with traditional plastic and showed great application potential in fruit preservation. [ABSTRACT FROM AUTHOR]

As an emerging non-contact cold chain preservation technology, the impact of the DENBA+ on plant cell wall metabolism and its mechanism of inhibiting softening have not been addressed. In this study, strawberries were used as an experimental model to investigate the effect of space electric field storage on cell wall metabolism. Compared with the control, 500 V DENBA+ treatment was able to reduce the firmness loss of strawberries by 18.3 % on 18 d. Additionally, the DENBA+ exhibited a pronounced ability to suppress fruit softening enzyme (FaPG1 and FaβGal4) expression, delay the rise in polygalacturonates (PG), pectin methyl esterase (PME), cellulase (Cx), and β-galactosidase (β-Gal) activities, postpone the decline in cell wall matrix (CWM), insoluble solid pectin (ISP), and colloidal soluble pectin (CSP) content along with hemicellulose and cellulose levels while attenuating water-soluble pectin (WSP) accumulation during cold storage period. These findings contribute to the maintenance of fruit cell wall structural integrity with the aim of sustaining strawberry firmness and retarding the progression of aging. • DENBA+ delayed the degradation of strawberry cell walls. • DENBA+ inhibited the cell wall-modifying enzymes activities of strawberry. • DENBA+ keeps the strawberries from softening. • DENBA+ affected the expression levels of FAPG1，FaPME1 and FaβGAL4. [ABSTRACT FROM AUTHOR]

Bio-enzymatic grafting phenolic acid to chitosan derivative is an efficient and environmentally friendly molecular synthesis technology. In the present study, N-carboxymethyl chitosan (CMCS) was grafted with gallic acid (GA) using recombinant bacterial laccase from Streptomyces coelicolor as a catalyst. GA and CMCS were successfully grafted as determined by measuring amino acid content, Fourier transform infrared (FTIR) spectroscopy and ultraviolet-visible (UV-Vis) spectroscopy. Then, the effect of GA-g-CMCS coating on the freshness of strawberries at 20 ± 2 °C was explored. The physiological and biochemical quality indicators of strawberries during storage were monitored. The 1.5% GA-g-CMCS coating helped to protect the antioxidant properties and nutrients of strawberries and extend the shelf life. Specifically, it reduced the weight loss of strawberries during preservation (originally 12.7%) to 8.4%, maintained titratable acidity content (TA) residuals above 60% and reduced decay rate from 36.7% to 8.9%. As a bioactive compound, GA-g-CMCS has the potential to become an emerging food packing method. These results provide a theoretical basis and reference method for the subsequent synthesis and application of CMCS derivatives. [ABSTRACT FROM AUTHOR]

Chlorine dioxide (ClO 2) exhibits promising potential for the application in food preservation. However, the large-scale production of controlled-release ClO 2 films faces challenges. The sodium chlorite microcapsules (Micro-SC) were successfully prepared in this study using polyvinyl alcohol (PVA) as the wall material through the spray drying method. Furthermore, A large-scale preparation of temperature and humidity dual-responsive ClO 2 controlled-release films (Micro-SC@EVA) was achieved using melt extrusion. The film could release ClO 2 triggered by water vapor for 36 days. The antibacterial effects were significantly enhanced with the increase of microcapsule ratio from 4 % to 8 %. The Micro-SC@EVA film reduced the total viable count and wight loss of strawberries, inhibits ethylene production, and extended the shelf life of by 150 % compared with the control group at 25 °C. The application evaluation results show that the novel approach for the large-scale preparation of ClO 2 controlled-release film holds significant implications for food packaging. [Display omitted] • The prepared Micro-SC could generate ClO 2 without adding extra acid. • The production of ClO 2 controlled-release films stably in large-scale. • The controlled-release ClO 2 film could release for 36 days and exhibits a dual-response to temperature and humidity. • The controlled-release ClO 2 film could extends the shelf life of strawberries by 150 %. [ABSTRACT FROM AUTHOR]

In this study, an antimicrobial component, silk protease inhibitors (SPIs), was extracted from discarded silkworm cocoons, and a suitable degumming method for obtaining regenerated silk fibroin (SF) was screened. An edible antimicrobial coating was prepared by mixing SPIs with SF for evaluation of potential in strawberries preservation. Results demonstrated that SPI could effectively inhibit mycelial growth and spore germination. The alkaline protease method exhibited the highest degumming rate of 24.4 %. The SPI-SF coating exhibited excellent mechanical properties, high water vapor permeability, and easy washability. Within 10 days, seedlings treatment with SPI-SF coating solution showed a germination rate of 94.3 %, and exhibited good biocompatibility with HepG2 cells. Coating with SPI-SF led to increase in the storage period of strawberries to 10–14 days, concurrent with considerable reduction in decay rate at room temperature. Conclusively, this study demonstrates the potential of SPI-SF edible coating in strawberries preservation. [Display omitted] • Silk protease inhibitors (SPI) effectively inhibited Botrytis cinerea. • Silk fibroin (SF) degummed by alkaline protease had superior film-forming property. • SPI-SF benefited the fresh keeping of strawberries as antifungal coating materials. [ABSTRACT FROM AUTHOR]

Currently, the valorization of agricultural waste, such as red onion peel, has gained more attention due to their rich source of antioxidants and antibacterials with potential applications in the post-harvest preservation of fruits. In this study, methanolic extracts from red onion peel were incorporated into the oil-in-water emulsion stabilized by alginate (1% and 2%) with and without 0.5% carboxymethyl cellulose (CMC). The results showed that the mixture of 2% alginate and 0.5% CMC retained the antioxidant activity, especially ABTS free radical scavenging activity (827.26–1112.56 mg/L) during the first 27-day refrigeration of emulsions. Additionally, the degradation of anthocyanins was divided into two phases following Weibull model. Phase 1 lasted for 23 days with high stability of anthocyanin (33.61–39.28 mg/L, 82.6–89.7% retention) while this value decreased to 49.1–65.2% (19.27–21.90 mg/L) over the remaining 10 days (phase 2) for 2% alginate samples. Meanwhile, the figures for 1% alginate samples were 76.5–78.8% (31.09–31.27 mg/L) and 70.2–76.3% (21.83–23.85 mg/L) for phases 1 and 2, respectively. The addition of 0.5% CMC retained anthocyanin for a longer time at 1% alginate but retained more anthocyanin at higher alginate concentration although for a shorter duration. As an edible coating for strawberry preservation, an emulsion composed of red onion peel extracts stabilized by 2% alginate and 0.5% CMC was utilized. The coating effectively inhibited total aerobic microbes, particularly total coliforms, as evidenced by their non-detection during the initial 4–6 days of refrigeration. Moreover, no signs of E. coli or Salmonella were found throughout storage. Nevertheless, it is noteworthy that coating lacked the capacity to retard the growth of yeasts and molds (about 2.7 log CFU/g for all samples). [ABSTRACT FROM AUTHOR]

Fresh strawberries are easily contaminated by microorganisms after picking. Therefore, how to effectively store and keep fresh strawberries has been a hot topic for scientists to study. In this study, we prepared a leaf shaped metal organic framework nanomaterial loaded with quercetin (Quercetin@ZIF-L) at first, which can achieve effective loading of quercetin (96%) within 45 min and has a controlled release effect under acidic conditions. In addition, by cleverly combining satellite graphene oxide @ silver nanoparticles (GO@AgNPs) with slow precipitation performance, Quercetin@ZIF-L/GO@AgNPs nanocomposite film with larger pore size and larger specific surface area was prepared by scraping method. The characterization data of water flux, retention rate, flux recovery rate and water vapor permeability show that the composite film has good physical properties. The experiment of film packaging showed that the fresh life of strawberry could be extended from 3 to 8 days, which significantly improved the storage and freshness cycle of strawberry. At the same time, the metal migration test proved that the residual amount of silver ion in strawberry met the EU standard and zinc ions are beneficial to the health, enriching the types of high-performance fresh-keeping materials and broadening the application. [Display omitted] • Rapid and efficient adsorption and stimulated release of natural active substances-quercetin by MOFs. • MOFs composite nano cling film significantly prolongs the shelf life of strawberries. • Collaborative antibacterial preservation performance of MOFs and GO @ Silver Nanoparticles. [ABSTRACT FROM AUTHOR]

Incorporating polysaccharide-based composite films with nanobiotechnology offers a new strategy for food preservation. This study initially focuses on the preparation of tea polyphenol nanoparticles (TPNP), novel and derived from natural antibacterial agents, which serve to improve stability. Afterwards chitosan-based composite films loaded with TPNP (CTN film) were developed using solution casting method. The incorporation of TPNP significantly improved the UV/water/oxygen barrier properties, mechanical properties and thermal stability, alongside notable physical properties including water contact angle (93.65 ± 0.04°), low water vapor permeability (33.72 ± 3.32 g/m2h) and oxygen permeability (0.11 ± 0.02 g/m2h), tensile strength (61.83 ± 0.70 %), and elongation at break (31.60 ± 6.12 %). The CTN film not only exhibited exceptional biodegradability and nontoxicity, but also demonstrated remarkable antimicrobial efficacy against Escherichia coli and Bacillus subtilis. Additionally, it showcased potent antioxidant activity, boasting DPPH and ABTS radical scavenging rates up to 89.25 ± 0.18 % and 93.84 ± 0.42 %. The CTN film was successfully formed on the surface of strawberries through dip-coating process and their shelf life was extended from 4 to 6 days at 20 °C without side-effect on the weight loss, harness, pH and total soluble solids, illustrating its potential for enhancing food preservation. [ABSTRACT FROM AUTHOR]

In this study, multifunctional green carbon dots (CDs) have been synthesized using Galla chinensis waste (GCW) via hydrothermal method for the first time. An active packaging film has been developed in this work by combining CDs and pullulan (PL), using the solution-casting method. The microscopic morphology revealed that the CDs that were prepared using GCW exhibited good compatibility with PL. In addition, it also led to improvement in the toughness of the PL film (14.01 % to 20.26 %), along with its water vapor permeability value [1.31 to 0.53 (g·mm)/(kPa·h·m2)]. The composite films consisting of CDs exhibited good UV blocking rates for the UVA (90.41 %–7.87 %), UVB (87.76 %–0.08 %), and UVC (83.39 %–0 %) spectral ranges. The composite films exhibited strong antioxidant activity, and the clearance of ABTS and DPPH were obtained to be 93.61 % and 86.30 %, respectively. In addition, the composite films showed good antibacterial activity for E. coli and S. aureus , with a high antibacterial rate of up to 99.99 %. Finally, the non-contact preservation of strawberries over a duration of 10 d at room temperature confirmed that the prepared composite film can help preserve the quality of strawberries, as well as extended their shelf-life. [Display omitted] [ABSTRACT FROM AUTHOR]

• Pectin coatings enriched with WLE improved strawberry shelf-life. • WLE significantly reduced strawberry weight loss during storage. • Pectin-based coatings effectively preserved strawberries' bioactive compounds. Fruits that are characterized by their fragile architecture are less durable and are a major source of waste. Thus, research on increasing the durability of such foods remains relevant. Pectin is an inexpensive and edible coating material derived from natural resources that can be used to preserve strawberries. The aim of the current research was to fortify pectin with grape pomace extract (GPE) and wine lees extract (WLE) that are rich in bioactive components. Physicochemical, microbiological and functional properties of coated and uncoated strawberries were investigated during the storage period (0, 5, 10, 15, and 20th day). GPE and WLE-supported pectin coatings helped preserve the antioxidant capacity, phenolic, anthocyanin and ascorbic acid contents of strawberries. Coated samples WLE-enriched exhibited significantly less weight loss compared to other samples. WLE coating was effective in inhibiting yeast mould populations on strawberries. WLE-enriched coatings acted as a wall material to preserve bioactive components and delayed quality changes compared to GPE, allowing them to reach a storage period of 20 days at 4 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

A stronger and dimension-stabilized film was obtained using κ-carrageenan and sodium carboxymethyl starch (CMS) with carboxylated cellulose nanocrystals (C-CNC) as a reinforcing agent and anti-shrinkage agent. C-CNC endowed the films with better mechanical properties as well as excellent dimensional stability. The film solutions showed shear thinning and acted as a pseudoplastic fluid. When C-CNC content was increased from 0% to 12%, the tensile strength and elongation at break of the films improved from 23.89 MPa to 38.37 MPa and 21.00% to 27.31%, respectively. The films maintained good thermal stability and barrier performance. The Zeta potential of the film suspension can reach below −30 mV, indicating C-CNC enhanced the electrostatic repulsion in the film-forming system, which favored the network structure more continuous and stable. By virtue of the excellent mechanical properties and dimensional stability, strawberries can be tightly wrapped without cracks by the coatings to delay the deterioration greatly. By comparing the weight loss rate, Vc, total soluble solid, hardness, titratable acid and pH, CCC12-coated strawberries were closer to fresh ones. Therefore, this study has developed a feasible, low-cost and green fruit coating that can be potentially utilized on a large-scale. [Display omitted] • Sodium carboxymethyl starch and κ-carrageenan based films were prepared. • Carboxylated cellulose nanocrystals endowed films highly mechanical properties. • The film-forming solution could form a dimensional stable coating on strawberries. • The CCC12 showed a higher preservation for the strawberries obviously. [ABSTRACT FROM AUTHOR]

This study investigates the synthesis, characterization, and application of copper oxide nanoparticles (CuO NPs) for enhancing the shelf life of strawberries and exploring adjacent plasmonic phenomena. Utilizing both sol–gel and precipitation methods, the CuO NPs were synthesized, characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and exhibited high purity as confirmed by energy-dispersive spectroscopy (EDS). SEM analysis showed that nanoparticles created using the precipitation method were uniformly spherical and sized between 30 and 70 nm. BET analysis revealed a surface area of 58.76 m2/g, enhancing their antimicrobial effectiveness. The application phase involved coating strawberries with CuO NP–infused gelatin and glycerol solutions to assess their impact on fruit preservation. Increased concentrations of CuO NPs correlated with significant enhancements in preservation effectiveness, extending shelf life up to 27 days without spoilage. Additionally, the interaction of CuO NPs with light, despite lacking surface plasmon resonance, provides insightful implications for designing nanocomposites with improved functionalities for food packaging. This study underscores the potential of CuO NPs as promising nanomaterials for food preservation, offering a novel approach to reduce food waste and enhance food safety through innovative nanopackaging solutions.Graphical Abstract: This study investigates the synthesis, characterization, and application of copper oxide nanoparticles (CuO NPs) for enhancing the shelf life of strawberries and exploring adjacent plasmonic phenomena. Utilizing both sol–gel and precipitation methods, the CuO NPs were synthesized, characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and exhibited high purity as confirmed by energy-dispersive spectroscopy (EDS). SEM analysis showed that nanoparticles created using the precipitation method were uniformly spherical and sized between 30 and 70 nm. BET analysis revealed a surface area of 58.76 m2/g, enhancing their antimicrobial effectiveness. The application phase involved coating strawberries with CuO NP–infused gelatin and glycerol solutions to assess their impact on fruit preservation. Increased concentrations of CuO NPs correlated with significant enhancements in preservation effectiveness, extending shelf life up to 27 days without spoilage. Additionally, the interaction of CuO NPs with light, despite lacking surface plasmon resonance, provides insightful implications for designing nanocomposites with improved functionalities for food packaging. This study underscores the potential of CuO NPs as promising nanomaterials for food preservation, offering a novel approach to reduce food waste and enhance food safety through innovative nanopackaging solutions. [ABSTRACT FROM AUTHOR]

Recently, chitosan film has been widely used to extend the shelf life of food. In this study, high, medium and low molecular weight of chitosan were used as raw materials to prepare a series of films (C1–C27) by controlling the content of chitosan and glycerol, and their mechanical properties, water vapor permeability (WVP), oxygen transmittance (OP), morphology and antibacterial properties were characterized as well. The results indicated that all films had film-forming properties. Among them, the film C16 with high molecular weight, high chitosan content and 50% glycerol/chitosan (w/w) exhibited the excellent transparency (91.2%), elongation at break (28.948%), tensile strength (77.963 MPa), WVP (1.46 × 10−12gcm/cm2·sPa), smooth morphology, denser structure and antibacterial property (Staphylococcus aureus and Escherichia coli). Meanwhile, the preservation properties of chitosan films were evaluated by strawberry preservation. Almost all the studied films had better preservation effect than the commercially available PE films, especially of which the film C16 was the best compared with others. It maintained the physical and chemical parameters (weight loss ratio, total soluble solids, titratable acidity, total ascorbic acid and color change) of strawberry most obviously. Hence, chitosan films had great potential for the industrial application of fruit preservation. [ABSTRACT FROM AUTHOR]

Active food packaging with controlled release behavior of volatile antimicrobials is highly desirable for enhancing the quality of fresh produce. In this study, humidity-responsive antimicrobial aerogels were developed using chitosan and dialdehyde nanocellulose, loading with cyclodextrin-cinnamaldehyde inclusion complexes (ICs) for achieving humidity-triggered release of the encapsulated antimicrobial agent. Results showed that the prepared aerogels had capable water absorption ability, which could be served as absorbent pads to take in excessive exudate from packaged fresh produce. More importantly, the accumulative release rate of cinnamaldehyde from the antimicrobial aerogels was significantly improved at RH 98 % compared to that at RH 70 %, which accordingly inactivated all the inoculated Escherichia coli, Staphylococcus aureus and Botrytis cinerea. Additionally, strawberries packaged with the antimicrobial aerogels remained in good conditions after 5 d of storage at 22 ± 1 °C. The prepared composite aerogels had the potential to extend the shelf life of fresh strawberries. [Display omitted] • Bio-based aerogels were developed based on Schiff base reaction • Humidity-triggered release of volatile compound was achieved. • Changes in RH affected the crystal structure of ICs. • Packages loaded with antibacterial aerogel extended the shelf life of strawberries [ABSTRACT FROM AUTHOR]

Cinnamon essential oil (CEO) was emulsified by hydroxypropyl-β-cyclodextrin/ ethyl lauroyl arginate (HPCD/LAE) complex to make nanoemulsions, which were then incorporated into maltodextrin (MD) to prepare HPCD/LAE/CEO/MD microcapsules by spray drying. The starch/polybutylene adipate terephthalate (starch/PBAT, SP) based extrusion-blowing films containing above microcapsules were developed and used as packaging materials for strawberry preservation. The morphology, encapsulation efficiency, thermal and antibacterial properties of microcapsules with different formulations were investigated. The effects of microcapsules on the physicochemical and antimicrobial properties of SP films were evaluated. When the formula was 4 % HPCD/LAE-3% CEO-10% MD (HL-3C-MD), the microcapsule had the smallest particle size (3.3 μm), the highest encapsulation efficiency (84.51 %) of CEO and the best antibacterial effect. The mechanical and antimicrobial properties of the SP film were enhanced while the water vapor transmittance and oxygen permeability decreased with the incorporation of HL-3C-MD microcapsules. The films effectively reduced the weight loss rate (49.03 %), decay rate (40.59 %) and the total number of colonies (2.474 log CFU/g) and molds (2.936 log CFU/g), thus extending the shelf life of strawberries. This study revealed that the developed SP films containing HPCD/LAE/CEO microcapsules had potential applications in degradable bioactive food packaging materials. • Cinnamon essential oil (CEO) nanoemulsions were stabilized by HPCD/LAE complex. • The nanoemulsions were spray dried into microcapsules and incorporated into SP films. • The microcapsule addition significantly improved antibacterial property of SP films. • The films with microcapsules effectively extended the shelf life of strawberry. [ABSTRACT FROM AUTHOR]

In this work, a multifunctional preservative film of ZnO/carboxymethyl starch/chitosan (ZnO/CMS/CS) with the unique "Steel Wire Mesh" structure is fabricated by the chemical crosslinked of ZnO NPs, CMS and CS. Unlike traditional nano-filled polymer film, the formation of the "Steel Wire Mesh" structure of ZnO/CMS/CS film is based on the synergistic effect of ZnO NPs filled CMS/CS and the coordination crosslinked between CMS/CS and Zn2+ derived from ZnO NPs. Thanks to the "Steel Wire Mesh" structure, the tensile strength and water vapor barrier of 2.5ZnO/10CMS/CS film are 2.47 and 1.73 times than that of CS film, respectively. Furthermore, the transmittance of 2.5ZnO/10CMS/CS film during antifogging test is close to 89 %, confirming its excellent antifogging effects. And the 2.5ZnO/10CMS/CS film also exhibits excellent long-acting antibacterial activity (up to 202 h), so it can maintain the freshness and appearance of strawberries at least 5 days. More importantly, the 2.5ZnO/10CMS/CS film is sensitive to humidity changes, which achieves real-time humidity monitoring of the fruit storage environment. Note that the preparation method of the film is safe, simple and environmentally friendly, and its excellent degradation performance will not bring any problems of food safety and environmental pollution. [Display omitted] [ABSTRACT FROM AUTHOR]

This study used electrostatic spraying (ES) system as an efficient technique for strawberry preservation with chitosan (CH) coating. The effects of CH deacetylation degree (DD, 81.0, 88.1 and 95.2%) on the qualities (weight loss, pH, total soluble solids (TSS), firmness, flavonoids content, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity and mold growth) of strawberry during cold storage were investigated. Results showed that CH coating by ES formed more continuous and uniform protective layer compared with conventional spraying (CS). CH coating effectively enhanced the overall quality and extended shelf life of strawberry at least 2 days. CH coating with 81.0% and 88.1% DD were more effective in reducing weight loss of strawberry, and CH coating with 88.1% DD could better maintain TSS content, while CH coating with 95.2% DD delayed the decline in flavonoids more obviously. However, DD had no significant impact on pH, firmness, SOD activity, MDA and mold growth of coated samples. The evaluation criteria indicated CH coating with 88.1% DD had better preservation performance with the highest synthetic value (6.17) during storage. These findings suggest that CH coating especially with 88.1% DD by ES, as a safe, cheap and efficient technique, has great potential for industrial application of fruit preservation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrospun PVA/CS films loaded with 1,8-cineole/HP-β-CD ICs were developed. • The incorporation of ICs improved physicochemical properties of films. • PVA/CS/40% ICs film achieved the sustained release of 1,8-cineole. • PVA/CS/40% ICs film showed excellent antibacterial and antioxidant activity. • PVA/CS/40% ICs film extended the shelf-life of strawberries to 6 days. Development of food packaging systems containing essential oils (EOs) has gained increased attention recently. However, the instability of EOs restricts their application. Therefore, effective encapsulation of EOs is demanded for their protection and controlled release. In this work, 1,8-cineole, the major component in Eucalyptus globulus essential oil, was encapsulated into hydroxypropyl-β-cyclodextrin to form an inclusion complex, which was then incorporated into polyvinyl alcohol and chitosan composite polymer to fabricate nanofibrous film via electrospinning. The film with 40% (w/w) of inclusion complexes showed enhanced barrier and mechanical properties, and the release of 1,8-cineole from the film was sustained and dominated by the non-Fick diffusion. Moreover, this film could extend the shelf life of strawberries to 6 days at 25 ℃. This work suggested dual encapsulation of EOs by cyclodextrin and electrospun nanofibers is an ideal strategy to improve the availability of EOs, and the produced film is promising for food preservation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Date palm fruit waste extract (DPFW) loaded chitosan (Cs)/polyethylene glycol (PEG) biofilm was prepared. • DPFW extract displayed an impressive suppression effect against the identified pathogens in antimicrobial experiments. • As fresh strawberries were preserved using Cs/PEG packaging loaded with extract for 10 days. • The present findings imply that DPFW-3@Cs/PEG material can be successfully used to pack perishable fruits and vegetables. In light of the global concern that calls for the safe disposal of waste polluting the environment and its exploitation in adding many distinctive products that can be used practically, this study was conducted to clarify how to make the best use of such waste. Therefore, the presented research aims to eliminate these residues and use their extracts as antimicrobial materials that can be used for films/membranes preparation for food and fruit preservations with low economic feasibility. Based on that, the aim of our work was planned to prepare films of date palm fruit waste extract (DPFW) loaded chitosan (Cs)/polyethylene glycol (PEG) composite. The extract was added to the polymers mentioned above with three different concentrations to prepare three film samples (DPFW-1@Cs/PEG), DPFW-2@Cs/PEG and DPFW-3@Cs/PEG). All these films were compared with those prepared without DPFW (DPFW-0@Cs/PEG). The film solutions films were cross-linked using glyoxal as a crosslinker before films formation. The finding illustrated that, the surface structure of DPFW-loaded Cs/PEG became rough, and the extract was remarkably seen on the surface of Cs/PEG films. In addition, the water contact angle for all fabricated films revealed that the films are hydrophobic in nature. The thermal stability of Cs/PEG films were enhanced with the addition of DPFW. The DPFW extract displayed an impressive suppression effect against the identified pathogens in antimicrobial experiments. As fresh strawberries were preserved using Cs/PEG film loaded with DPFW for 10 days, it was discovered that the strawberry wrapped in the extract-containing films maintained their freshness superior to those wrapped in unloaded material. Such films have a wide range of potential applications in food packaging to extend the longevity of freshly prepared goods due to their simplicity and solid biocidal ability. The present research's findings imply that DPFW-3@Cs/PEG material can be successfully used to pack perishable fruits and vegetables. [ABSTRACT FROM AUTHOR]

The polymeric wall material of microcapsules has the function of encapsulation, protection, and controlled release of the active core material. In this study, sodium alginate (SA)-NaClO 2 solution was encapsulated in ethylcellulose (EC) microcapsules using an emulsion-solvent evaporation method. The EC/SA-NaClO 2 microcapsules were doped into polyvinyl alcohol (PVA) solution containing HCl, and an antimicrobial film was prepared using the solution casting method. Water vapor drives HCl into the interior of the microcapsules and reacts with NaClO 2 in the microcapsules to release ClO 2 gas to achieve antimicrobial properties. ClO 2 gas can effectively inhibit the growth and reproduction of bacteria and molds on strawberry surfaces. The antimicrobial film inhibited the growth of E. coli by 99.9% and reduced the area of B. cinerea to <10%. Storage bags prepared from antimicrobial films could extend the shelf life of strawberries and maintain their sensory characteristics such as color, hardness, and moisture. [Display omitted] • The antibacterial film can release ClO 2 gas at low humidity. • The antibacterial film was continuously released at 25 °C and 55% RH for about 200 h. • The film has excellent antibacterial properties against E. coli and B. cinerea. • The antibacterial film was used for packaging and storage of fruits and vegetables. • The antimicrobial film can extend strawberry shelf-life. [ABSTRACT FROM AUTHOR]

Water loss is a significant factor in fruit deterioration, and edible films offer a promising method to prevent this. Herein, a silk fibroin (SF)-based edible film reinforced by cellulose nanocrystals (CNCs) and chlorogenic acid (CGA) was developed. CNCs and CGA promote the formation of hydrogen bonds and β-sheets, thereby enhancing hydrophobicity and minimizing water vapor permeability (WVP). Compared with those of pure SF film (water contact angle: 80.3°; WVP: 2.235 × 10−10 g Pa−1 s−1 m−1), the water contact angle of the composite film increased to 90.1° and its WVP decreased to 1.246 × 10−10 g Pa−1 s−1 m−1. Moreover, the tensile strength (27.05 MPa) and Young's modulus (836.53 MPa) of the composite film also increased. Additionally, the antimicrobial activities of the composite film against Escherichia coli and Staphylococcus aureus were 99.66% and 91.07%, respectively. Furthermore, it inhibited the germination of fungal spores (Rhizopus stolonifer). Accordingly, the composite film increased the shelf life of strawberries to 15 d, which is longer than that with other reported films. This study provides an excellent strategy for producing antimicrobial fruit preservation films with high hydrophobicity and low WVP. • The prepared film has high hydrophobicity and low water vapor permeability. • The prepared film has great antimicrobial properties. • The prepared film can effectively prolong the shelf life of strawberries. [ABSTRACT FROM AUTHOR]

Strawberries are a widely consumed fruit that contains a variety of antioxidant metabolites. However, postharvest strawberries are highly perishable and susceptible to a variety of fungal pathogens. In this study, a chitosan-based coating containing turmeric (TU) and green tea (GT) extracts was developed and evaluated for the preservation of strawberries. Both TU and GT extracts contained high phenolic contents (>5.8 g kg−1 dry weight), but only TU extract showed strong antifungal activity. SEM observations revealed that high concentrations of extract (3–5% v/v) caused the formation of agglomerates within the films, reduced elongation at break and increased tensile strength. The postharvest treatment of strawberries with chitosan coating containing TU extract inhibited the proliferation of Botrytis cinerea during 7 d of storage at 20 °C, whereas the coating containing GT extract extended the antioxidant properties of postharvest strawberries from 4 to 8 d at 20 °C. Sensory analysis indicated that the coatings did not significantly affect flavor and taste. Overall, TU extract was used for the first time for food packaging purposes and proved to be a great complement to the antioxidant properties of GT to extend the shelf-life of postharvest strawberries. • Chitosan-based films containing turmeric and green tea extracts were evaluated. • Turmeric extract addition improved the antifungal activity against B. cinerea. • Green tea extract addition enhanced the antioxidant capacity of the film. • The tensile strength of the film increased after adding the extracts. • The developed films extended the shelf-life of postharvest strawberries. [ABSTRACT FROM AUTHOR]

The underutilized by-products of hydrophilicity olive mill wastewater phenols (OPs) have great antimicrobial potential. ZnO NPs is one of most wildly used nano material with anti-bacterial function as well. This study aimed to prepare the detoxified and antimicrobial-enhanced OPs capping ZnO nanoparticles (OPs-ZnO NPs) containing metal core of ZnO NPs and organic shell of OPs, respectively. The OPs-ZnO NPs was chemically coordinated/chelated driven by Lewis bases (NaOH) in aqueous solution. The results obtained by SEM and TEM showed that those irregular sphere OPs-ZnO NPs were ranged from 58 to 92 nm, with an OPs caption of 35.40% (w/w). Importantly, the in vitro results showed that the strategy of capping OPs in ZnO NPs decreased the toxicity of ZnO NPs (< 0.02 g/L). Moreover, OPs-ZnO NPs presented a higher stability in simulated gastrointestinal digestion (Zn2+ < 0.07 g/L after 12 h). The results also showed that the protective coating of OPs-ZnO NPs and OPs-ZnO NPs/CMC (carboxymethyl cellulose) enhanced the antimicrobial activity of Escherichia coli , Staphylococcus aureus and Aspergillus niger. Furthermore, the coating of OPs-ZnO NPs/CMC decreased the weight loss and the rotting ratio of fresh strawberry, and ultimately prolonged its shelf-life at least 4 days under 25 ºC. Therefore, this study provided a biosafety strategy for the preparation of detoxified and antimicrobial enhanced OPs-ZnO NPs and its CMC protective coating for fresh produce throughout storage. • OPs-ZnO NPs is prepared via olive phenols from olive mill wastewater. • The cytotoxicity to L929 and Caco-2 of OPs-ZnO NPs is decreased versus ZnO NPs. • The OPs-ZnO NPs exhibits stability in the simulated gastrointestinal digestion. • Nanocoating of OPs-ZnO NPs/CMC prolongs strawberry's shelf-life at room storage. [ABSTRACT FROM AUTHOR]

Antimicrobial packaging based on biodegradable material is a novel strategy to ensure food safety without posing threats to the environment. In this study, poly(lactic acid) (PLA) nanofibers containing Ethyl-Nα-dodecanoyl- l -arginate hydrochloride (LAE) were fabricated using the electrospinning method. The microstructure, inter-molecular interaction, thermal stability, and antimicrobial properties of electrospun films were characterized. The LAE embedded nanofibers had an average diameter of 325–364 nm, which was 43.5%–49.5% thinner compared to the neat PLA nanofibers. The active films demonstrated outstanding antimicrobial capability against Escherichia coli O157:H7, Staphylococcus aureus, and Botrytis cinerea. The active films with LAE could also effectively extend the shelf-life of strawberries at 25°C, suggesting that PLA films incorporating with LAE could be used as an environmental-friendly antimicrobial packaging material. • Uniform and bead-free nanofibers enriched with LAE were obtained by electrospinning. • The LAE/PLA films showed significant antimicrobial effects against E.coli O157:H7, S.aureus and B. cinerea. • The films with 2% LAE could effectively extend the shelf-life of strawberries stored at 25 °C. [ABSTRACT FROM AUTHOR]

• Sodium alginate and chitosan were assembled layer by layer to achieve self-healing. • The assembly properties and self-healing ability of coatings were characterized. • This self-healing coating can reduce the impact of coating damage on strawberries. Coating damage destroys the integrity features critical for maintaining the modified atmosphere inside the fruit. In this study, we developed a self-healing edible coating that maintains its barrier properties for extending the shelf life of strawberries. The coating was fabricated via the layer-by-layer assembly of chitosan (CS) and sodium alginate (SA). (SA/CS) 3 formed by three assembly cycles could completely heal the visibly damaged area by treating water. The mechanical properties and the water and oxygen rates of the healed coating were 97%, 63%, and 95%, respectively, of the intact coating. (SA/CS) 3 coating effectively delayed strawberry deterioration. Moreover, the coating reduced the impact of coating damage on strawberries by restoring the coating barrier properties. The present findings have important implications for solving the reduction in freshness caused by coating damage. [ABSTRACT FROM AUTHOR]

In this study, we fabricated polyvinyl alcohol (PVA)/chitosan (CS) bilayer films by casting and investigated the effects of preparation conditions and CS content (2, 2.5, or 3 wt.%) on the ability of these films to preserve packaged strawberries. The best performance was achieved at a CS loading of 2.5 wt.% (ultrasound time, 25 min); the strain and stress values were 143.15 ± 6.43% and 70.67 ± 0.85 MPa, respectively, oxygen permeability was 0.16 ± 0.08 cm2·m2·day−1·MPa−1, water vapor permeability was 14.93 ± 4.09 g·cm−1·s−1·Pa−1, and the shelf life of fresh strawberries packaged in the PVA/CS 2.5 wt.% bilayer film was determined to be 21 days at 5 ± 2 °C and a relative humidity of 60 ± 5%. Treatment with PVA/CS bilayer films prevented the decrease in the firmness of strawberries during storage (21 days). The evaluated physicochemical parameters (weight loss, decay, firmness, titratable acidity, soluble solid content, ascorbic acid content, and color) indicated that treatment with PVA/CS bilayer films led to better maintenance of the fruit quality. We believe that our study makes a significant contribution to literature because it paves the way to the fabrication of smart packaging materials and facilitates the commercialization of fresh strawberries as an important health food. [ABSTRACT FROM AUTHOR]