Plastic Wrap Research Articles

Preservation effects of chitosan/polyvinyl alcohol/clove essential oil antifungal film on yellow peaches: Physicochemical properties and fruit quality assessment

Using antifungal food packaging films presents a significant opportunity to prolong the shelf-life of food products. In this work, a chitosan-polyvinyl alcohol antibacterial film, enriched with clove essential oil (CS/PVA/CEO), was developed for preservation effects on yellow peaches, and its physical properties and structure were investigated. The good compatibility and thermal stability of CS/PVA/CEO film were demonstrated via scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. Mechanical properties are exhibited at a 0.75% CEO concentration: the tensile strength is (25.09 ± 0.32) MPa, elongation at break is (291.23 ± 2.53)%, water vapor permeability is (0.479 ± 0.005) g·mm·m−2·h−1·kPa−1, water resistance is (18.57 ± 0.35)%, and water resistance is (9.70 ± 0.26)%. During the 11 days of storage at temperatures ranging from 23 °C to 26 °C and 26 days of storage at 4 °C–5 °C, the CS/PVA/CEO film exhibited effective preservation of yellow peach fruits. CS/PVA/CEO group extended 3–4 d at room temperature and 5–10 d at 4 °C of yellow peaches preservation compared with the CS/PVA and control groups. This effectiveness was evaluated based on various parameters, including fruit appearance, decay rate, respiratory intensity, malondialdehyde concentration, firmness, total soluble solids, and titratable acidity. Therefore, adding CEO into the antifungal film demonstrated excellent potential in enhancing the preservation of yellow peaches.

Bio-based composite active film/coating from deccan hemp seed protein, taro starch and leaf extract: Characterizations and application in grapes

This study aimed to create a novel, cost-effective, and environmentally friendly food packaging film or coating using agricultural waste materials such as deccan hemp seeds and leaves. The process involved blending deccan hemp seed protein and leaf extract at an optimal ratio through a casting technique. Additionally, starch isolated from taro root was added into the protein-based film to enhance its structural, barrier, and mechanical properties. The introduction of bioactive compounds, like deccan hemp leaf extract, led to increase in antioxidant activity and enriching the film with beneficial phenolic compounds.The combination of leaf extract and starch with the protein film resulted in a homogeneous, dense, and smooth film matrix, as evidenced by scanning microscopy images. FTIR spectroscopy confirmed interlinkage among the various constituents in the film. Rheological analysis of the film-forming solution showed its shear-thinning behavior, with the storage modulus exceeding the loss modulus in the angular frequency range of 0.1 rad/s to 100 rad/s, indicating the film's elastic nature. Furthermore, the physical and optical attributes of the films were enhanced through the addition of starch and leaf extract.In a practical application, the film-forming solution was applied to grapes, leading to improved quality and extended shelf life for grapes stored under ambient conditions for ten days. Overall, this study's findings suggest that the use of deccan hemp seed protein-based packaging film holds promise as an emerging solution for enhancing the shelf life of vegetables and fruits, offering a sustainable and effective alternative for food packaging.

The fate of plastic wraps in constructed wetland: Surface structure and microbial community

The high use of plastic wraps leads to significant environmental pollution. In this study, the surface structure and microbial community evolution of commercially available plastic wraps [polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), and polylactic acid (PLA)] in constructed wetlands (CWs) were investigated. The results indicated that all plastic wraps gradually decreased in molecular weight, crystallinity, melting, and crystallization temperatures, whereas a gradual increase was observed in the surface roughness, polymer dispersity index (PDI), carbonyl index (CI) and Shannon index of microorganisms colonizing the CWs. The aging rate of the plastic wrap was in the order: PLA > PVC > PE > PVDC, at the same site in the CWs, and it was in the order: soil surface > plant roots > subsoil, for the same plastic wrap. The diversity of microorganisms colonizing the same plastic wrap was in the order: plant roots > subsoil > soil surface. The Shannon indices of microorganisms on plastic wraps were lower than those in the soil, indicating that the diversity of microorganisms colonizing plastic wraps is limited. Additionally, the microbial community structure on the plastic surface was co-differentiated by the plastic type, placement position in the CWs, and aging time. Significantly different microbial community structures were found on the PVC and PVDC wrap surfaces, revealing that the chlorine in plastics limits microbial diversity. Unclassified members of Rhizobiaceae and Pseudomonadaceae were the dominant genera on the surface of the plastic wraps, suggesting that they may be the microorganisms involved in plastic degradation processes. The study provides valuable perspectives to facilitate a comprehensive understanding of the migration, fate, and environmental risks associated with microplastics (MPs) in wetlands.

Valorization of Wine Lees: Assessment of Antioxidant, Antimicrobial and Enzyme Inhibitory Activity of Wine Lees Extract and Incorporation in Chitosan Films

Wine lees, as one of the main by-products of winery wastes, is considered a rich source of bioactive compounds such as polyphenols. Recovery of such bioactive compounds would amplify the valorization of winery by-products, as well as promote their use in cosmetics and health applications. Towards this aim, the objective of this work is the recovery of phenolic compounds from wine lees by ultrasound-assisted extraction. The effect of extraction time, and ethanol content on the extraction yield of total phenolics was investigated, while the phenolic profile of the extract was monitored by GC-MS. Under the optimized conditions, the total phenolic content was calculated at 302.6 mg gallic acid equivalents g− 1 dry extract; the dry extract was investigated for its biological activities, exhibiting excellent antioxidant and antimicrobial activity. Moreover, the extract was found to be a potent inhibitor of tyrosinase, elastase, collagenase, α-glucosidase, and α-amylase with IC50 values of 53.3, 83.5, 82.7, 19.0, and 31.3 µg mL− 1, respectively. Finally, the wine lees dry extract was incorporated into chitosan films, reinforcing the properties of the films, and providing them with excellent antioxidant activity. The results support that wine lees extract exhibits high antioxidant activity and can be used as a highly efficient inhibitor of enzymes with pharmaceutical and health interest. Moreover, the chitosan film enriched with wine lees extract is a promising material with high antioxidant potential and can lead to the development of novel food packaging films in the food industry.Graphical

Occurrence of Stem Rot on Acacia mangium Caused by Amauroderma subresinosum.

Acacia mangium has the characteristics of developed root system, nitrogen fixation and soil improvement, fast growth and high yield, and improvement of soil fertility. It is often used as a windbreak tree species in rubber plantations, a highway shade tree, for coastal and mountain restoration in Hainan . In October 2021, a stem rot disease with an incidence of 3% was found in Baisha city(19°22'18″N,109°16'58″E), Hainan Province, China. In the early stage of the disease, the crown showed chlorotic leaves, followed by defoliation. In later stages, whole tree dieback was observed. The basal tissue of the stem of the diseased tree had white rot, and black-brown basidiocarps were observed about 1 m away from the ground. The basidiocarps surface of fresh was disinfected with 75 % ethanol, the epidermal tissue was removed, and the inner tissue blocks were transferred to PDA medium. After culturing in dark at 28°C for 3 days, a colony with white aerial mycelium was isolated and designated: HNBSMZXS20211011001. The basidiocarp was dark brown, sessile, mostly one-year-old, and the cap is nearly semi-circular, wooden, slightly shiny, with a size of 14.7 to 18.1cm × 9.5 to 10.1 cm. The base is thick (5 to 6.5 cm) and the edge is thin (0.3 to 0.7 cm). The basidiospores are oval, 10.7 to 13.65μm × 6.7 to 9.06μm in size, with a double-layer wall. The outer wall is transparent and the inner wall is light yellow. The basidiospores contain 1~2 oil droplets. The morphological features are consistent with those of Amauroderma subresinosum (Murrill) Corner (Zhang et al., 2000). The basidiocarps and type strain cultures were stored as accessions in the Laboratory of Plant Pathogen Fungus Biology, Hainan University. For pathogenicity tests, sawdust culture medium was used (soft sawdust 82%, wheat bran 15%, glucose 2%, gypsum 1%, mixed with water in proportion, sterilized at 121°C for 40min). The mycelium plug from a fresh culture (d=5mm) was taken from the edge of the colony of type strain, and transferred to the sterilized sawdust medium. When mycelium has colonized the media, it was used to inoculate plants. Media without mycelium was used as a control. Naturally growing seedlings (three year old) of A.mangium were selected from the teaching nurseries of Hainan University (20°6'25''N,110°32'24''E). First, 75 % alcohol was sprayed on the stem of the base of A.mangium for surface disinfection. After the surface was dried, a slight wound (about 4×2cm) was made on the surface with a sterilized scalpel. A inoculated and control sawdust media rods were tightly attached to the wound, moistened with cotton balls soaked in sterile water, and then fixed with plastic wrap, and the outer layer was wrapped with newsprint. Inoculation and controls were replicated three times. Two months after inoculated, the stems of the plants inoculated with the isolated fungus grew white hyphae and showed white rot symptoms, and the leaves became chlorotic and defoliated with complete tree decline in six months, which was consistent with the original symptoms observed. By comparison, white callus had grown on the edge of the stem wounds of the control plants. The same fungus was re-isolated from the inoculated plants and confirmed as A.subresinosum based on the internal transcribed spacer (ITS), the ribosomal large subunit(LSU), and the translation elongation factor 1-α(EF1-α) gene sequence, the fungus was not isolated from control plants thus fulfilling Koch's postulates. The ITS region of r-DNA, the ribosomal large subunit(LSU), the translation elongation factor 1-α gene(EF1-α) were amplified using ITS1/ITS4(White et al. 1990), LR0R/LR5(Hu et al. 2021), EF1-983F/EF1-1567R(Buckley et al. 2005) primers, respectively. The sequences of ITS (OQ674500), LSU (OQ674502) and EF1-α gene (OQ883944) were submitted to GenBank. Through with BLAST, the identities of the ITS, LSU and EF1-α sequences to A.subresinosum (GenBank Accession no. ITS: LC176755; LSU: MK119903 and EF1-α: MK121572) was 99.82%; 99.15% and 99.82%, respectively, the identities were more than 99 %. It was reported that A.subresinosum could infect Casuarina equisetifolia and Areca catechu(Chen et al., 2016; Cheng. 2017; Wu et al., 2019). However, this is the first report of Amauroderma subresinosum causing stem rot of Acacia mangiumin Hainan, China. This report will facilitate field diagnosis and provide scientific reference for further research on the disease.

The Diversity of Plant as Traditional Culinary Food Wrappers on The Bogor’s Society, West Java Province, Indonesia

AbstractTraditional culinary is a food that has a distinctive taste, commonly consumed by a particular society. Generally, traditional culinary using the diversity of plants to wrap food. The function of plant leaves for food wrapping in consider of natural and safe material. The use of natural materials is very valuable traditional knowledge and includes cultural wealth. The research was conducted to reveal the diversity of plants that are still used as traditional culinary wrapping in Bogor city. This research method used the ethnobotany approach, through observation and direct interview to a key informant up to 20 respondents on the three traditional market’s in Bogor city. The data collection results were produced of 23 types of cuisines in the traditional culinary markets, namely Anyar/Kembang, Sukasari, and Surya Kencana. These traditional culinary are utilized five plant species to wrap food, mostly using banana leaves (Musa spp.) for food packaging of 23 types of the tradisional culinary delights. The advantage of utilizing plants as traditional culinary wrapping infused with flavor to enhance the taste and art. Utilization plants as food wrapping need to preserved, developed, and socialized to public due to its local wisdom environmental sustainability and to reduce the use of non-natural resources that have severe environmental impacts and public health.AbstrakKuliner tradisional merupakan suatu makanan yang mempunyai cita rasa yang khas, biasa dikonsumsi oleh masyarakat tertentu. Umumnya kuliner tradisional memanfaatkan keanekaragaman tumbuhan sebagai pembungkusnya. Penggunaan daun sebagai pembungkus karena bahan alami dan aman untuk membungkus makanan. Penggunaan bahan dari alam adalah pengetahuan tradisional sangat berharga dan termasuk kekayaan budaya. Penelitian tersebut dilakukan untuk mengungkap keanekaragaman tumbuhan yang masih digunakan sebagai pembungkus kuliner tradisional di Kota Bogor. Metode penelitian menggunakan pendekatan etnobotani, melalui observasi dan wawancara langsung kepada informan kunci sebanyak 20 responden di tiga pasar tradisional kota Bogor. Hasil pendataan menunjukkan terdapat 23 jenis kuliner tradisional di pasar Anyar/Kembang, Sukasari, dan Surya Kencana. Kuliner tradisional ini memanfaatkan 5 jenis tumbuhan sebagai pembungkusnya yang sebagian besar adalah daun pisang (Musa spp.) yang digunakan sebagai pembungkus 23 kuliner tradisional. Keuntungan memanfaatkan tumbuhan sebagai pembungkus kuliner tradisional antara lain untuk menambah cita rasa dan seni. Pemanfaatan tumbuhan sebagai pembungkus makanan perlu dilestarikan, dikembangkan, dan disosialisasikan kepada masyarakat umum agar budaya lokal ini senantiasa lestari dan dapat mengurangi pemanfaatan sumber daya non alam yang berdampak buruk terhadap lingkungan dan kesehatan masyarakat.

The Effect of Gestational PFOS Exposure on Metabolism in the F344 Rat

Perfluorooctanesulfonate (or PFOS) is a type of PFOA known as (per-and poly-fluorinated alkylated substance) which is a manufactured compound chemical made of a strong carbon-fluorine and sulfonic acid. Due to its hydrophobic and lipophobic properties, industries use it in food wrappers, fire-fighting foam, sweat-proof clothing, and household cleaning products. PFOS exposure is an endocrine disruptor that may induce Metabolic Syndrome (MetS), an association of disorders that increases the risk of significant health issues like heart disease, diabetes, and stroke. Gestational and lactational exposure to Perfluorooctanesulfonate (PFOS) in F344/Stm rats was hypothesized to induce metabolic dysfunction in both female and male offspring. Pregnant F344 rats were given a control diet or diet containing 15mg/kg or 30mg/kg of PFOS; measures of body weight and body composition through nuclear magnetic resonance (NMR) were performed, and tissue was measured at the euthanasia of the dams. Both female and male offspring exposed during pregnancy and lactation were subject to the same protocol with tissue collection at three ages. On both low and high doses of PFOS, the pregnant females showed a decreased body weight gain compared to the control group; males and females also showed decreased body weight at three weeks of age when weaned from the exposed female. At 16 weeks of age, the same patterns were not revealed. The results from NMR suggested a 21% decrease in fat percentage and a 23% decrease in fat for the high exposure in the dams. The offspring at three weeks old showed a reduction in fat mass, fat mass %, and fat-free % in both high and low-dose groups compared to the control group; on the other hand, at 16 weeks old, this trend is not shown. The results suggest that PFOS had a short-term metabolic effect on the offspring at the younger; however, at the adult age, they seem to recover their initial phenotypes. For future studies, it suggested the focus on underlying mechanisms responsible for the rodent's recovery. ASPIRE Program (R25HL168782) Medical College of Wisconsin. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Sustainable chitosan/polyvinyl alcohol composite film integrated with sulfur-modified montmorillonite for active food packaging applications

Sulfur-functionalized montmorillonite (S-MMT), which has strong antioxidant and antibacterial activities, was prepared by forming a sulfur-amine complex using ethylenediamine (EDA). S-MMT was added to the chitosan/polyvinyl alcohol (Chi/PVA) blend polymer to develop an active food packaging film. The composite film, especially 4 wt% S-MMT-added Chi/PVA film (Chi/PVA/S-MMT4%), showed significant increases in tensile strength (∼25.1 %), elongation at the break (∼94.1 %), and UV-blocking ability (98.2 % UV-A and 100 % UV-B) compared to the neat Chi/PVA film. The Chi/PVA/S-MMT4% film also exhibited remarkable antioxidant properties (100 % ABTS and 65.4 % DPPH scavenging activity) and potent antibacterial activity (stopped the growth of L. monocytogenes and E. coli). Chicken packaged in the composite film showed a significant reduction in quality changes, including appearance, pH, thiobarbituric acid reactive substances (TBARS), and total viable colonies (TVC) over 20 days of storage. Multifunctional Chi/PVA/S-MMT films have high potential in active food packaging applications.

Effect of Soybean Oil on the Improvement of the Functionality of Edible Membrane-Type Food Packaging Films Based on Caseinate-Carboxymethyl Chitosan Compositions.

Edible film biopolymers are gaining attention to tackle problems of plastic waste and food safety to alleviate environmental problems associated with plastic products in food packaging. In this study, caseinate-carboxymethyl chitosan (CA-CMCH) composite films were made with the incorporation of soybean oil (SO) using a casting technique. The influence of different soybean oil concentrations at 0, 0.5, and 1% (w/w) on physical, mechanical, barrier, and surface characteristics of films composed of caseinate-carboxymethyl chitosan (CA-CMCH) was evaluated. The brightest film (L* value of 95.95 ± 0.30) was obtained with the edible film made from the control group of samples with sodium caseinate (NaCA-100; 100% NaCA). The results also indicated that samples with 1% SO in NaCA-75 and CaCA-75 had lower water vapor permeability (WVP), while those with NaCA-50 and CaCA-50 showed higher values of WVP. For mechanical properties, this study found that incorporating soybean oil into the caseinate-carboxymethyl (CA-CMCH) composite films led to an enhancement of both tensile strength and elongation at break. The morphological structures, determined using SEM, of control and composite films showed compact and homogenous surfaces. Overall, the addition of soybean oil contributed to the improvement of the functional properties of the edible films, offering potential solutions to the environmental issues associated with plastic packaging and enhancing the safety and performance of food packaging.

Evaluation of Polymeric Films Based on Starch and Antimicrobial Compounds as an Alternative to Replace Food Wrap

One of the macromolecules most used as a replacement alternative for some conventional packaging materials is starch. This is due not only to its high bioavailability and economy, but also to its positive environmental impact. However, this material presents important physical-mechanical limitations, such as: high permeability to water vapor, rigidity, fragility, hygroscopicity and tendency to retrograde. Additionally, the incorporation of antimicrobial compounds in the polymer matrix enhances the use of these films, and the addition of plasticizers and reinforcing materials improves their mechanical properties so that they can increasingly compete with synthetic polymers.

Alginate Films Enriched in Raspberry and/or Black Currant Seed Oils as Active Food Packaging.

Alginate films plasticized with glycerol and enriched in raspberry and/or black currant seed oils were prepared via casting solution techniques. The intention was to create active films for food packaging where antioxidants in a film would deactivate oxidants in a packed product or its surroundings, improving conditions inside packaging and extending the shelf life of such a product. The prepared materials were characterized by physicochemical, spectroscopic, mechanical, water vapor transmission (WVTR), and antioxidant activity analysis. Infrared spectra of the alginate films with oils were similar to those without the additive; the band with a maximum at about 1740 cm-1 stood out. The prepared materials with oils were thicker, contained less water, were more yellow, and were less permeable to water vapor. Moreover, the presence of the oil in the films resulted in a slightly lower Young's modulus and lower stress at break values but higher strain at break. The antioxidant capacity of raspberry seed oil itself was about five times higher than that of black currant seed oil, and a similar trend was noticed for films modified with these oils. The results indicated that both oils could be used as active substances with antioxidant properties in food packaging.

UV Radiation and Protein Hydrolysates in Bio-Based Films: Impacts on Properties and Italian Salami Preservation.

UV radiation was combined with the incorporation of fish protein hydrolysates to improve the performance of active bio-based films for food packaging. UV radiation was not used previously to enhance the packaging performance of blend films of starch/protein, and fish protein hydrolysates were not incorporated in bio-based polymer surfaces previously. Rice starch and fish proteins (from Whitemouth croaker muscle) were utilized to prepare films by the casting technique, which were UV-radiated under different exposure times (1, 5, and 10 min). The packaging performance of the films was determined according to the mechanical and barrier performance, solubility, and color. Fish protein hydrolysates (from Argentine croaker muscle) were then incorporated into the films (bulk structure or surface). The results showed that UV radiation for 1 min increased the tensile strength and modified the optical properties of films. It also altered the structure of the polymeric matrix, as demonstrated by the microstructure and thermal analysis, in agreement with the data obtained in packaging properties. The evaluation of antioxidant capacity through 2,2-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and reducing power indicated that incorporating fish protein hydrolysates either in the films' bulk structure or film surface promoted antioxidant properties; control films (produced with rice starch/fish proteins without hydrolysates) also presented antioxidant potential. According to the peroxide value and thiobarbituric acid reactive substance (TBARS) assays, control films and the films containing hydrolysates in their bulk structure or on the surface could prevent the lipid oxidation of Italian salami. Thus, combining UV radiation to shape the characteristics of bio-based materials with fish protein hydrolysates to reduce lipid oxidation contributes to the performance of active bio-based films for food packaging.

Enhanced antibacterial and antioxidant activities of chlorogenic acid loaded sweet whey/starch active films for edible food packaging

Starch and whey protein are potential biomaterials for the development of biodegradable and edible food packaging. In this study, chlorogenic acid (CGA), an eco-friendly natural extract, was firstly added to sweet whey/starch matrix as a bioactive compound to develop biodegradable active packaging materials. The results showed that when the ratio between starch and sweet whey was 10:1, water resistance and toughness of sweet whey/starch blend films were improved significantly. After the addition of CGA, the active films showed excellent UV barrier, antibacterial and antioxidant properties. When the addition of CGA reached 3%, UV barrier (at 315 nm), antibacterial (against Escherichia coli) and antioxidant (ABTS method) properties of the active films were increased by 54.6%, 47.5% and 74.5% compared with sweet whey/starch matrix. The presence of CGA could form new hydrogen bonds in the matrix and affect the interactions between sweet whey and starch, which increased swelling rate and toughness of the active films. Preservation experiments of fresh bananas could indicate that the presence of CGA can effectively exert antioxidant effects and inhibit the browning of bananas. As an edible inner coating or film, CGA loaded sweet whey/starch active material has good application potential in the field of food packaging.

Sourcing chitin from exoskeleton of Tenebrio molitor fed with polystyrene or plastic kitchen wrap

In this work we have characterized and compared chitin sourced from exoskeleton of Tenebrio molitor larvae fed with polystyrene or plastic kitchen wrap combined with bran in the ratio 1: 1 with chitin sourced from larvae exoskeleton fed only with bran. Analysis of the frass by ATR-FTIR showed very similar spectra and confirmed degradation of the plastic feed components, while ATR-FTIR analysis of the exoskeleton verified the absence of any plastic residue. Deproteinization followed by demineralization produced 6.78–5.29 % chitin, showing that plastic (polystyrene or plastic kitchen wrap) in the larvae diet resulted in heavier insect exoskeleton, but yielded slightly less chitin, with the lowest value obtained for plastic kitchen wrap in the insect diet. The deacetylation degree of 98.17–98.61 % was determined from measured ATR-FTIR spectra. XRD analysis confirmed the presence of α-chitin with a crystallinity index of 66.5–62 % and crystallite size 4–5 nm. Thermogravimetric analysis showed similar degradation curves for all chitin samples, with two degradation steps. These results show that chitin sourced from exoskeleton of T. molitor larvae fed with plastic (polystyrene or plastic kitchen wrap) and contributing to significant biodegradation of major polluting materials can be a feasible and alternative source of chitin, further promoting a bio-circular economy.

Swan-feathers inspired smart-responsive sustainable carboxymethyl cellulose/polyvinyl alcohol based food packaging film for robustly integrated Intelligent and Active Packaging

The integration of advanced packaging technology with innovative multifunctional bio-based materials emerges as a promising next-generation strategy to tackle two enduring challenges in food storage technology: food spoilage and counterfeiting. Inspired by the superhydrophobic properties of swan feathers, this study developed a smart-responsive, sustainable food packaging film called C-CPQ using carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA). The as-prepared C-CPQ film exhibited remarkable hydrophobicity and water-vapor barrier properties owing to its novel design featuring an asymmetric bionic feather-like barbed texture, representing significant advancements in CMC/PVA-based packaging materials. Additionally, C-CPQ exhibited satisfactory mechanical strength, biodegradability, and film-forming capabilities. Notably, incorporating quercetin（QR） endowed C-CPQ with exceptional pH-sensing, fluorescence, antioxidant, UV-shielding, and antibacterial properties, enabling intelligent and active food packaging. Consequently, C-CPQ exhibited UV-stimulated photochromic characteristics and fatigue-resistant food anti-counterfeiting capabilities while extending food shelf life to 5 days, surpassing conventional PE packaging by 2 days. Moreover, the integration of smartphones enabled highly sensitive, rapid, and real-time visual monitoring of food degradation under natural light. The findings of this study present promising outcomes under real-world conditions, serving as a framework for the development of sustainable, high-performance modern food packaging with comprehensive real-time visual freshness monitoring, anti-counterfeiting, and preservation functionalities.

Electrospun superhydrophobic polyvinyl chloride /polydimethylsiloxane-nanodiamond nanocomposite with enhanced antifouling and mechanical properties for fresh produce packaging

Food package films serve the important functions of preserving food quality, extending shelf life, and protecting against external contaminants while also providing a barrier to moisture and oxygen. In consideration of the increasing frequency of foodborne outbreaks, there is a growing demand for food packaging films with additional functionality to prevent cross-contamination and the attachment of pathogens, thereby enhancing bacterial safety. Herein, we report a one-step fabrication approach relying on electrospinning of a blend of polyvinyl chloride (PVC) and polydimethylsiloxane (PDMS) together with nanodiamond (ND) on a rotating drum collector for the formation of bacterially antifouling food package films. In this approach, by adjusting the concentrations of PVC, PDMS, and ND and the drum angular velocity, the nanofiber diameter could be tuned in the range of 0.4 μm to 2.0 μm. Furthermore, these process parameters could also be used to modulate the water contact angle on the resultant films, with a minimum contact angle of 136.2 ± 5.6° and a maximum of 159.5 ± 3.8°. The lowest water contact angles were observed for films with bare PVC fibers while the highest contact angles were seen for films with nanocomposite fibers containing ND and PVC/PDMS. Compared with the films with bare PVC, nanocomposite films with ND-PVC/PDMS achieved up to 99.8 % and 99.6 % reduction in bacterial adhesion against S. typhimurium LT2 and Listeria innocua, respectively. The tensile strength of nanofibrous PVC film can be increased from 1.2 ± 0.4 MPa to 4.4 ± 0.3 MPa by the inclusion of PDMS (1:1 wt.%) and further increased to 8.9 ± 0.3 MPa with the additional inclusion of ND (PVC/PDMS/ND 1:1:0.1 wt.%). Considering the notable antifouling properties against bacteria and the improved mechanical characteristics, these nanocomposite films represent a noteworthy step in the development of sustainable and active food packaging solutions for a safer and healthier food supply chain.

Pickering nanoemulsion loaded with eugenol contributed to the improvement of konjac glucomannan film performance

Konjac glucomannan (KGM) is becoming a very potential food packaging material due to its good film-forming properties and stability. However, KGM film has several shortcomings such as low mechanical strength, strong water absorption, and poor self-antibacterial performance, which limits its application. Therefore, in order to enhance the mechanical and functional properties of KGM film, this study prepared Pickering nanoemulsion loaded with eugenol and added it to the KGM matrix to explore the improvement effect of Pickering nanoemulsion on KGM film properties. Compared to pure KGM film and eugenol directly added film, the mechanical strength of Pickering-KGM film was significantly improved due to the establishment of ample hydrogen bonding interactions between the β-cyclodextrin inclusion complex system and KGM. Pickering-KGM film had significant antioxidant capacity than pure KGM film and eugenol directly added KGM film (eugenol-KGM film) (~3.21 times better than KGM film, ~0.51 times better than eugenol-KGM film). In terms of antibacterial activity, Pickering-KGM film had good inhibitory effect on Escherichia coli, Staphylococcus aureus, and Candida albicans, and raspberry preservation experiment showed that the shelf life of the Pickering-KGM film could be extended to about 6 days. To sum up, this study developed a novel means to improve the film performance and provide a new insight for the development and application of food packaging film.

Preparation, Characterization and Application of Active Food Packaging Films Based on Sodium Alginate and Twelve Varieties of Mandarin Peel Powder.

The industrial processing of mandarin fruits yields a large amount of peel waste, resulting in economic losses and environmental pollution. The peels of mandarin fruits are a good source of biomass and active substances that can be used to produce food packaging systems. In this study, active food packaging films were prepared based on sodium alginate and twelve varieties of mandarin peel powder. The structures, properties, and corn oil packaging performance of the films were compared. Results showed that the twelve varieties of mandarin peel powder differed in pectin, lipid, protein, crude fiber, and total phenol contents. The prepared films all exhibited a yellow color, 117.73-152.45 μm thickness, 16.39-23.62% moisture content, 26.03-90.75° water contact angle, 5.38-8.31 × 10-11 g m-1 s-1 Pa-1 water vapor permeability, 5.26-12.91 × 10-20 m2 s-1 Pa-1 oxygen permeability, 4.87-7.90 MPa tensile strength, and 13.37-24.62% elongation at break. Notably, the films containing mandarin peel powder with high pectin and lipid contents showed high moisture/oxygen barrier ability and mechanical properties. The films containing mandarin peel powder with high total phenol content exhibited high antioxidant- and antimicrobial-releasing abilities and good performance in delaying corn oil oxidation. Overall, the results suggested that the films have good application potential in active food packaging.

Cassia Seed Gum Films Incorporated with Partridge Tea Extract as an Edible Antioxidant Food Packaging Film for Preservation of Chicken Jerky.

The use of edible packaging films to delay food spoilage has attracted widespread attention. In this study, partridge tea extract (PTE) was added to cassia gum (CG) to prepare CG/PTE films. The microstructure, optical, mechanical, barrier, and antioxidant properties of CG/PTE films were investigated, and the effect of PTE on CG films was shown. The films had high transparency and smooth surface structure. Additionally, PTE significantly improved the elongation at break and antioxidant activity of films. At 2.5% of PTE, the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging rate of the film was 46.88% after diluting 50 times, indicating excellent antioxidant property, which could be applied to food preservation. After 9 days of storage, the thiobarbituric acid reactive substances values (TBARS) of chicken jerk packaged with films containing 0% and 2.5% PTE increased from 0.12% to 1.04% and 0.11% to 0.40%, respectively. This study suggests that CG/PTE films can be used to preserve cooked meat.

Analysis of Mechanical and Thermal Properties of Polymer Materials Derived from Recycled Overprinted Metallized PP Films.

Polymer materials and their composites are one of the most frequently used materials in the packaging and food industries. This applies to both disposable and reusable packaging, layered films with barrier properties, as well as densely overprinted polymer films and metallized food wrap films. According to statistical data from Plastics Europe, approximately 40% of processed thermoplastics are used to produce packaging, including single- and multi-layer film packaging. Growing requirements and new EU directives require the use of recycled materials in new products, which is not easy because the properties of recyclates may differ significantly from those of the primary materials with which the former are mixed. This work attempts to analyze the properties of the primary material used to produce a film using the casting method in comparison with the industrial recyclate obtained by the processing of film made of the primary material and then overprinted and metallized. The process of obtaining re-granulates and preparing test samples was presented, and the mechanical, structural, and thermal properties of the tested materials were compared. The conducted research and the obtained results demonstrated the advisability of conducting advanced mechanical recycling, which leads to obtaining re-granulates with repeatable processing properties and thermal and mechanical properties comparable to the original material despite the impurities they contain.