Sustainable Packaging Materials Research Articles

Utilization of Nanocellulose as an Eco-friendly Sustainable Nanomaterial for Potential Pathway to Circular Economy and Sustainability

The development of sustainable packaging materials has been a major challenge in the packaging industry. The recyclability of nanocellulose plays an important role in promoting sustainability and the advancement of a circular economy through the provision of renewable and eco-friendly feedstocks as alternatives to traditional materials. This paper aims to highlight the challenges and opportunities presented by nanocellulose as a sustainable and multifunctional packaging material. In addition, this paper discusses the current state of the art of nano cellulose and nano inorganics as sustainable alternatives to synthetic plastics. The sustainability of packaging materials is an ineluctable challenge for the packaging industry, which should be developed within a circular economy, with minimum environmental impacts. In this context, nanocellulose remains one of the most promising derivatives from renewable resources because it shows excellent recyclability, biodegradability, and multi-functional properties. This review aims to point out different prospects of nanocellulose for being a bio-alternative to conventional packaging materials, hence examining challenges and opportunities regarding its application. The paper also discusses recent advances in the combination of nanocellulose with nano-inorganics as promising alternatives to synthetic plastics, providing an overview of its role in fostering sustainability in the packaging industry.

Photocatalytic rice bran protein/carboxymethyl cellulose/ZrO2 fiber produced by microfluidics: Formation mechanism, bacteriostasis and strawberry preservation

Developing cost-effective and environmentally sustainable active packaging materials remains an important challenge. We have developed rice bran protein (RBP)-based fibers incorporating carboxymethyl cellulose (CMC) and ZrO2 nanoparticles (ZrO2 NPs, 0 %–7 %, m/m) using microfluidic spinning. The integration of RBP, CMC, and ZrO2 NPs formed a robust hydrogen bond network that enhanced the fibers' thermal stability and crystallinity, reduced surface hydrophobicity, and aligned the molecular orientation. Under the catalysis of visible light (300 W, 12 h), ZrO2 NPs in the fiber produced reactive oxygen species, which inhibited the oxidative stress resistance system of Bacillus subtilis and destroyed its biofilm and DNA, thus showing excellent antibacterial effect. Additionally, during storage, this fiber also showed the ability to scavenge ethylene, thereby reducing the rate of loss of luminance, hardness and weight of strawberries. This study offers a new idea for RBP fiber in food preservation, antibacterial, and value-added utilization of rice bran by-products.

Selecting sustainable packaging materials and strategies: A holistic approach considering whole life cycle and customer preferences

With the increasing public awareness of packaging and the environmental impact caused by it, companies are driving their businesses to introduce and promote practices that help ease the negative impact of packaging on the environment. Studies done on consumer behaviour show that decisions nowadays are influenced by sustainability. Yet, companies struggle with changing practices and justifying adopting environmentally friendly packaging materials. The current paper presents a holistic approach, addressing the need for identifying, assessing, and selecting sustainable materials for packaging applications. The Kano model prioritises features that are then used with Ashby plots for identifying alternative materials. Life cycle assessment, as well as life cycle costing, are used for assessing the environmental and financial impact of the use of such materials. Automatically weighted Multi-Criteria Decision-Making Analysis (MCDA) is used to select the most appropriate packaging material. This methodology provides a combinatorial ranking for each criterion set by four pre-defined weight distributions for Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS). The proposed methodology allows for a systematic and holistic design process when deciding on packaging materials for any product. The methodology is validated for the case of packaging weather-sensitive cast stone products and carbonated drinks. In cast stone, three packaging materials are ranked for pallets based on their attributes. Similarly, for carbonated drinks, three packaging materials are recommended at the end of the study.

Processing and Properties of Polyhydroxyalkanoate/ZnO Nanocomposites: A Review of Their Potential as Sustainable Packaging Materials.

The escalating environmental concerns associated with conventional plastic packaging have accelerated the development of sustainable alternatives, making food packaging a focus area for innovation. Bioplastics, particularly polyhydroxyalkanoates (PHAs), have emerged as potential candidates due to their biobased origin, biodegradability, and biocompatibility. PHAs stand out for their good mechanical and medium gas permeability properties, making them promising materials for food packaging applications. In parallel, zinc oxide (ZnO) nanoparticles (NPs) have gained attention for their antimicrobial properties and ability to enhance the mechanical and barrier properties of (bio)polymers. This review aims to provide a comprehensive introduction to the research on PHA/ZnO nanocomposites. It starts with the importance and current challenges of food packaging, followed by a discussion on the opportunities of bioplastics and PHAs. Next, the synthesis, properties, and application areas of ZnO NPs are discussed to introduce their potential use in (bio)plastic food packaging. Early research on PHA/ZnO nanocomposites has focused on solvent-assisted production methods, whereas novel technologies can offer additional possibilities with regard to industrial upscaling, safer or cheaper processing, or more specific incorporation of ZnO NPs in the matrix or on the surface of PHA films or fibers. Here, the use of solvent casting, melt processing, electrospinning, centrifugal fiber spinning, miniemulsion encapsulation, and ultrasonic spray coating to produce PHA/ZnO nanocomposites is explained. Finally, an overview is given of the reported effects of ZnO NP incorporation on thermal, mechanical, gas barrier, UV barrier, and antimicrobial properties in ZnO nanocomposites based on poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate). We conclude that the functionality of PHA materials can be improved by optimizing the ZnO incorporation process and the complex interplay between intrinsic ZnO NP properties, dispersion quality, matrix-filler interactions, and crystallinity. Further research regarding the antimicrobial efficiency and potential migration of ZnO NPs in food (simulants) and the End-of-Life will determine the market potential of PHA/ZnO nanocomposites as active packaging material.

Novel, eco-friendly α-tocopherol/layered double hydroxides/poly(3-hydroxyoctanoate)-based active packaging materials with enhanced antimicrobial, barrier and antioxidant activities

Among various climate actions taken as a response to environmental concerns, important and highly influential are ones related to the packaging industry being still one of the largest plastic sectors responsible for the majority of post-consumer wastes. Therefore, in this manuscript, for the first time assessment of the potential application of biodegradable bacterially derived poly(3-hydroxyoctanoate) (P(3HO)) doped with functional 2D nanoparticles as a more sustainable active packaging material has been investigated. In particular, P(3HO) combined with two types of layered double hydroxide (LDHs) modified with α-tocopherol (type of vitamin E) was applied for the fabrication of polymeric nanocomposite films and a comprehensive investigation of their structure and relevant properties (mechanical, barrier, bactericidal, and antioxidative) was performed. Permeation study revealed that P(3HO)-based films with 4 wt% tocopherol-modified nanoparticles meet the barrier requirements for storing fruits and vegetables, whereas antibacterial assay indicated inhibited growth of Gram-positive bacteria (particularly S. Aureus). Monitoring of polyphenols (PPH) content in strawberries after 6 days of storage at room conditions showed a slightly higher level of PPH with reference to fresh fruits, which indicates the preserved freshness of strawberries kept in P(3HO) containing 4 wt% Zn-based LDHs modified with tocopherol contrary to fruits kept in commercial polypropylene packaging which led to significant drop in PPH content. Thus, the application-focused experiments indicated that investigated P(3HO)-based nanocomposites are promising candidates for more sustainable active packaging that may extend the shelf-life of fruits and protect consumers from food-borne pathogenic bacteria.

Hemp cellulose-based aerogels and cryogels: From waste biomass to sustainable absorbent pads for food preservation

This study presents a circular economy approach utilizing hemp stems and rice straw, typically perceived as low-value agricultural waste, to develop a sustainable alternative to traditional plastic absorbent pads for food packaging. The development of an active material was achieved through the utilization of hemp cellulose and a bioactive extract isolated from rice straw. In addition to reducing plastic pollution, this material demonstrates the potential to enhance food preservation. This research provides evidence of the benefits of repurposing agricultural by-products to create valuable and environmentally-friendly products. Hemp cellulose was extracted, characterized, and processed to develop stable aerogels and cryogels through supercritical CO2 drying and freeze-drying. The water stability and internal structure of the materials were guided via TEMPO-mediated oxidation and high-pressure homogenization. Both materials showed versatile physicochemical and mechanical properties. Nevertheless, with higher water sorption (2.20 mL/g), minimal dimensional changes, and lower shrinkage, cryogels were suitable for meat absorbent pad application. To enhance the cryogels functionality, they were impregnated with a rice straw bioactive extract in two different concentrations. The incorporation of the extract did not affect the structure of the cryogels, improved their mechanical properties and the antioxidant activity remained stable after drying (63.89–78.96 %). Finally, the performance of the developed materials was compared to commercial plastic pads and pristine meat preservation challenge test during 9 days at refrigeration conditions. The incorporation of rice straw extract improved meat color preservation. While moderate extract concentrations (75 mg/g) showed a protective effect against lipid oxidation, higher levels (187.5 mg/g) induced pro-oxidant reactions. This research highlights the potential of hemp cellulose-based cryogels as sustainable and functional packaging materials for meat products.

Polysaccharide-Based Bioplastics: Eco-Friendly and Sustainable Solutions for Packaging

Over the past few decades, synthetic petroleum-based packaging materials have increased, and the production of plastics has surpassed all other man-made materials due to their versatility. However, the excessive usage of synthetic packaging materials has led to severe environmental and health-related issues due to their nonbiodegradability and their accumulation in the environment. Therefore, bio-based packages are considered alternatives to substitute synthetic petroleum-based packaging material. Furthermore, the choice of packing material in the food industry is a perplexing process as it depends on various factors, such as the type of food product, its sustainability, and environmental conditions. Interestingly, due to proven mechanical, gas, and water vapor barrier properties and biological activity, polysaccharide-based bioplastics show the potential to expand the trends in food packaging, including edible films or coatings and intelligent and active food packaging. Various chemical modifications, network designs, and processing techniques have transformed polysaccharide materials into valuable final products, particularly for large-scale or high-value applications. Transitioning from petroleum-based resources to abundant bio-based polysaccharides presents an opportunity to create a sustainable circular economy. The economic viability of polysaccharide-based bioplastics is determined by several factors, including raw material costs, production technologies, market demand, and scalability. Despite their potential advantages over traditional plastics, their economic feasibility is affected by continuous technological advancements and evolving market dynamics and regulations. This review discusses the structure, properties, and recent developments in polysaccharide-based bioplastics as green and sustainable food packaging materials.

Recent Trends in the Synthesis of Monomers for Furanoate Polyesters and Their Nanocomposites’ Fabrication as a Sustainable Packaging Material

Furanoate polyesters are an extremely promising new class of materials for packaging applications, particularly furanoate-based nanocomposites, which have gained a high interest level in research and development in both academia and industries. The monomers utilised for the synthesis of furanoate-based polyesters were derived from lignocellulosic biomass, which is essential for both eco-friendliness and sustainability. Also, these polyesters have a lower carbon footprint compared to fossil-based plastics, contributing to greenhouse gas reduction. The furanoate-based nanocomposites exhibit enhanced performance characteristics, such as high thermal stability, excellent mechanical strength, superior barrier resistance, and good bacteriostatic rate, making them suitable for a wide range of industrial applications, especially for food-packaging applications. This paper reviews the recent trends in the synthesis routes of monomers, such as the various catalytic activities involved in the oxidation of 5(hydroxymethyl)furfural (HMF) into 2,5-furandicarboxylic acid (FDCA) and its ester, dimethyl furan-2,5-dicarboxylate (DMFD). In addition, this review explores the fabrication of different furanoate-based nanocomposites prepared by in situ polymerization, by melt mixing or solvent evaporation methods, and by using different types of nanoparticles to enhance the overall material properties of the resulting nanocomposites. Emphasis was given to presenting the effect of these nanoparticles on the furanoate polyester’s properties.

Wheat Bran and Saccharomyces Cerevisiae Biomass’ Effect on Aerobic and Anaerobic Degradation Efficiency of Paper Composite

This study is a continuation of research on sustainable food packaging materials made from locally available feedstock and industrial by-products within the Baltic Sea region. Its main focus is the impact of wheat bran filler and Saccharomyces cerevisiae additive, which was used to develop a novel bio-coating for paper composite packaging, on the biodegradation efficiency of paper composites under aerobic and anaerobic conditions. In this study, we analyzed the effect of 15% and 40% concentrations of wheat bran filler and Saccharomyces cerevisiae biomass on the biodegradation efficiency of paper composites. This research was conducted under controlled environmental conditions, with aerobic biodegradation tested at 46 °C in a compost-based mesophilic–thermophilic environment and anaerobic biodegradation tested at 55 °C in an active inoculum thermophilic environment. The results show that the presence of wheat bran filler significantly improves biodegradation efficiency compared to microcrystalline cellulose reference material. Under aerobic conditions, the biodegradation efficiency for the 40% wheat bran and yeast sample was 6.34%, compared to only 0.71% for the cellulose reference material. In anaerobic conditions, the 15% wheat bran and yeast sample showed a biodegradation efficiency of 96.62%, compared to 82.32% for the cellulose reference material.

Fabrication of collagen-sodium alginate based antibacterial and edible packaging material: Performance evaluation using Entropy-Combined Compromise Solution (CoCoSo)

In this research, we developed two alternative packaging materials: collagen-sodium alginate-pomegranate peel powder (CSP) and collagen-sodium alginate-chitosan (CSC), leveraging solid waste from both the leather and food industries. A comparative analysis was done between CSP and CSC film to evaluate their efficacy and potentiality as sustainable packaging material. CSC film showed reduced water solubility (39.4 %), water vapor transmission rate (27.3 gh-1m-2), and opacity (0.6 A600/mm) along with improved contact angle (69.7°) compared to CSP film. However, CSP film exhibited improved mechanical strength (10.9 MPa) and biodegradability (72.1 %) along with reduced oxygen permeability (0.6 meq/kg) compared to CSC film. Furthermore, CSP and CSC films showed significant inhibitory effect against two commonly available pathogen strains. A hybrid Entropy-Combined Compromise Solution (CoCoSo) analysis results demonstrated the superior performance of CSC films (γi=3.049) as packaging material. The edibility of the film was confirmed through pathogen test, in vitro cytotoxicity and stimulated digestibility assays. Additionally, from the thermal analysis it is apparent that the optimum degradation temperature for CSC film was 584 °C which is higher than any other green packaging material reported in the literature. Therefore, this study can pave the way for the fabrication of thermally stable edible packaging material from waste sources.

Fabrication of bamboo nanocellulose fibril-based food packaging with dual-antimicrobial property

The development of cellulose-based packaging films with excellent antimicrobial properties and biocompatibility has garnered significant attention. In this work, nanocellulose fibrils (NCFs) derived from from bamboo parenchyma cells were utilized to fabricate nanocomposite film with antimicrobial properties. This system exhibited distinct release behaviors for two antimicrobial agents, with the slow release of Ag nanoparticle (AgNP) in the initial stage contributed to delaying food spoilage, while the subsequent pH change in the microenvironment facilitated the release of essential oil of sour orange blossoms (SEO) for secondary antimicrobial activity. Additionally, the composite film demonstrated improved thermal stability and UV blocking capacity. Moreover, AgNP has been proven to enhance the mechanical properties, with the tensile strength of the novel composite film increasing by 34.85 % compared to control group. The water vapor permeability and oxygen permeability of the novel composite film were reduced, which could potentially reduce weight loss and slow down the rate of after-ripening. Following the acidification treatment, the films containing EO@MPN (essential oil encapsulated with metal-polyphenol network) component performed different antimicrobial patterns, indicating their pH-responsive antimicrobial capabilities, and they are effective against both Gram-positive and Gram-negative bacteria. After a 24-h exposure to a food simulant, the release amount of Ag was measured at 67.6 μg/dm2, within the acceptable limit, and the release profile of Ag was characterized. Cytotoxicity and Live/Dead staining tests confirmed that the novel composite film film had no significant toxicity, thus making it safe for application in food preservation. Furthermore, in a 15-day preservation experiment with mangoes, the novel composite film demonstrated the best performance, underscoring its potential as a sustainable antimicrobial packaging material.

Recycled Low Density Polyethylene Reinforced with Deverra tortuosa Vegetable Fibers

In this work, natural fibers extracted from the medicinal aromatic plant Deverra tortuosa, with different sizes (S1 = 2 mm and S2 = 500 μm), were incorporated into recycled low density polyethylene (rLDPE) to produce sustainable biocomposites. Compounding was performed with different fiber concentrations (0 to 30% wt.) via twin-screw extrusion followed by injection molding. Based on the samples obtained, a comprehensive series of characterization was conducted, encompassing morphological and mechanical (flexural, tensile, hardness, and impact) properties. Additionally, thermal properties were assessed via differential scanning calorimetry (DSC), while Fourier transform infrared spectroscopy (FTIR) was used to elucidate potential chemical interactions and changes with processing. Across the range of conditions investigated, substantial improvements were observed in the rLDPE properties, in particular for the tensile modulus (23% for S1 and 104% for S2), flexural modulus (47% for S1 and 61% for S2), and flexural strength (31% for S1 and 65% for S2). Nevertheless, the tensile strength decreased (15% for S1 and 46% for S2) due to poor fiber–matrix interfacial adhesion. These preliminary results can be used for further development in sustainable packaging materials.

Biopolymers as Sustainable and Active Packaging Materials: Fundamentals and Mechanisms of Antifungal Activities.

Developing bio-based and biodegradable materials has become important to meet current market demands, government regulations, and environmental concerns. The packaging industry, particularly for food and beverages, is known to be the world's largest consumer of plastics. Therefore, the demand for sustainable alternatives in this area is needed to meet the industry's requirements. This review presents the most commonly used bio-based and biodegradable packaging materials, bio-polyesters, and polysaccharide-based polymers. At the same time, a major problem in food packaging is presented: fungal growth and, consequently, food spoilage. Different types of antifungal compounds, both natural and synthetic, are explained in terms of structure and mechanism of action. The main uses of these antifungal compounds and their degree of effectiveness are detailed. State-of-the-art studies have shown a clear trend of increasing studies on incorporating antifungals in biodegradable materials since 2000. The bibliometric networks showed studies on active packaging, biodegradable polymers, films, antimicrobial and antifungal activities, essential oils, starch and polysaccharides, nanocomposites, and nanoparticles. The combination of the development of bio-based and biodegradable materials with the ability to control fungal growth promotes both sustainability and the innovative enhancement of the packaging sector.

Dual cross-linked network of the active starch film by incorporating palmitic acid and geraniol: A comprehensive evaluation of the hydrophobic mechanism and antimicrobial activity

In this study, (3-Aminopropyl) triethoxysilane (APTES) was employed as a bridging agent to enhance the compatibility between the hydrophilic starch/pectin film and the hydrophobic palmitic acid (PA) coating through hydrogen bonding and chemical reactions. To address the insufficient antibacterial activity of starch films, geraniol was also incorporated. The intermolecular interactions among APTES, PA, and starch were confirmed using x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and hydrogen nuclear magnetic resonance spectroscopy (1H NMR). Notably, the inclusion of APTES and PA significantly increased the film's hydrophobicity, resulting in a water contact angle (WCA) of 95.12°, a water vapor permeability (WVP) of 2.08 × 10−10 g/(mm·s·Pa), and an oxygen permeability (OP) of 2.61 × 10−9 g·mm·mm−2·s−1. Molecular dynamics (MD) simulations revealed strong non-covalent interactions and exceptional compatibility between starch and PA. Furthermore, the integration of pectin and geraniol improved the mechanical strength and antimicrobial properties of the modified films compared to unmodified starch films. These environmentally friendly and biodegradable starch-based films present a promising option for sustainable packaging materials in food preservation.

Influence of Plasticizers Concentration on Thermal, Mechanical, and Physicochemical Properties on Starch Films

The increasing demand for sustainable packaging materials has driven the exploration of biodegradable alternatives to synthetic plastics. This study investigates the thermal and mechanical properties of starch-based films plasticized with varying concentrations of glycerol and sorbitol. Cornstarch films were prepared with glycerol and sorbitol plasticizers in different ratios, and their physical characteristics, including swelling index, water solubility, and thermal stability, were assessed using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and tensile testing. The results indicate that the incorporation of plasticizers significantly influenced the films’ properties. Films with higher glycerol content exhibited greater flexibility and solubility, while sorbitol-plasticized films showed enhanced thermal stability. The combination of both plasticizers yielded films with balanced properties suitable for food packaging applications. This study demonstrates the potential of glycerol and sorbitol as effective plasticizers in developing biodegradable starch-based films, offering a promising alternative to conventional plastic packaging.

Metal-phenolic networks spontaneously reinforced carrageenan-based packaging films with antibacterial and antioxidant properties

The burdens of microbial food safety and environmental contamination make it necessary to search sustainable, safe, antibacterial and antioxidant active food packaging materials. This contribution proposed the use of copper-ferulic acid networks (CuFA NWs) as antibacterial substances. By immobilizing CuFA NWs into carrageenan matrix, a CuFA network-reinforced carrageenan-based packaging film (Carr/CuFA) was obtained via spontaneously hydrogen bond and electrostatic interaction indicated by ATR-IR and XPS. Interestingly, the addition of CuFA NWs increased the mechanical strength, surface hydrophobicity, and water vapor barrier properties of the carrageenan-based film, and imparted the film with UV-shielding capacity. Importantly, the Carr/CuFAx film exhibited effective antioxidant activity, and antibacterial performance against four foodborne bacteria. As a result, after confirming the safety of Carr/CuFA3 films by releasing, hemolysis and cell viability experiments, the Carr/CuFA3 film exhibited great potential in the safety control and preservation of fresh fruit by using blueberry and cherry as model fruit. In summary, this work provides a feasible candidate for the preservation and contamination control of fresh fruit.

Cordia dichotoma fruit mucilage and flaxseed oil nanoemulsion loaded bioactive film: Synergistic approach to enhance antimicrobial properties and bread shelf-life

Recently, non-conventional sources of mucilage have gained significant attention due to their exceptional techno-functional properties and easy availability. This study aimed to utilize Cordia dichotoma fruit mucilage (CDM) for fabricating bioactive films to evaluate the shelf-life of bread. For the development of nanoemulsion, different concentrations of flaxseed oil (1–5% w/w) were employed. Selection was carried out based on droplet size, encapsulation efficiency, and antimicrobial activity. The selected nanoemulsion (CDM-FO1) was subsequently used to develop CDM-based films with the incorporation of carboxymethyl cellulose (CMC) and sodium alginate (SA). Results revealed that the droplet size of the nanoemulsions was significantly increased from 101.25 ± 4.68 nm to 205.15 ± 7.14 nm with increasing flaxseed oil concentration. However, the addition of CMC and SA improved the tensile strength (13.97 ± 0.34 MPa) of the CDM-F11 film compared to control films CDM (6.98 ± 0.68 MPa) and CDM-FC (7.76 ± 1.65 MPa). The CDM-F11 film exhibited excellent barrier properties compared to the control film. The control film showed higher yeast and mold growth, starting at 0.84 ± 0.57 Log CFU/g on the 3rd day and increased to 3.12 ± 0.39 Log CFU/g by the 9th day. In contrast, the CDM-FC film demonstrated better antimicrobial properties, with microbial growth at 0.52 ± 0.39 Log CFU/g on the 3rd day and 2.84 ± 0.38 Log CFU/g on the 9th day. Overall, CDM film loaded with flaxseed oil nanoemulsion can be effectively used as a sustainable food packaging material with enhanced antimicrobial efficiency for bread preservation.

Ocean Plastics: Extraction, Characterization and Utilization of Macroalgae Biopolymers for Packaging Applications

This review details the extraction, characterization and utilization of seaweed-derived biopolymers for future packaging applications. The review is contextualized within the broader scope of the challenge of plastic pollution and the current urgent need for more sustainable packaging materials. Macroalgae (or seaweed) has been highlighted as a promising source of biopolymers, most commonly sodium alginate, agar and carrageenan, for reasons such as a rapid growth rate and decreased environmental impact when compared with terrestrial plant life. Extraction methods detailed include traditional solvent-based extraction and more sustainable developments such as ultrasound-assisted extraction, microwave-assisted extraction and bead milling. This review additionally presents the characterization techniques most pertinent in determining the applicability of these biopolymers in packaging applications. Properties of key importance to the development of sustainable packaging materials such as thermal properties, mechanical strength, barrier properties and biodegradability are highlighted in comparison to conventional petroleum-based plastics. This review concludes by realistically identifying the challenges faced by implementing seaweed-based biopolymers into packaging structures, such as cost-effectiveness, scalability and performance while suggesting future directions to mitigate these issues and improve the commercial viability of these materials for the packaging industry.

Enhancement of mechanical, barrier, and functional properties of chitosan film reinforced with glycerol, COS, and gallic acid for active food packaging

The demand for eco-friendly and natural food packaging materials has sparked considerable interest in the research and development of sustainable active packaging materials. In this study, a chitosan-based film was developed using glycerol as a plasticiser, chitooligosaccharide (COS) as an additive, and gallic acid as a cross-linking agent. The physical, barrier, mechanical, morphological, thermal, and functional properties of fabricated films were measured. The bio-composite film showed significantly lower moisture content (from 24.28 to 17.01%), water solubility (from 41.56% to 31.03%), water vapour permeability (14.63 to 9.79 × 10−9 gm−1s−1Pa−1), and light transmittance (from 63.67% to 21.71%) compared to neat chitosan film. Furthermore, the bio-composite film exhibited higher tensile strength (57.66 MPa) and elongation at break (88.76%), smooth microstructure, strong DPPH and ABTS radicals scavenging capacity, and good antimicrobial activity towards E. coli, L. innocua, and S. cerevisiae, and non-toxic to HaCaT cells indicating promising potential for use in sustainable active food packaging.

High-barrier, flexible, hydrophobic, and biodegradable cellulose-based films prepared by ascorbic acid regeneration and low temperature plasma technologies

Regenerated cellulose (RC) films are considered a sustainable packaging material that can replace non-degradable petroleum-based plastics. However, their susceptibility to water vapor and oxygen can limit their effectiveness in protecting products. This study introduces a novel approach for enhancing RC films to create durable, flexible, hydrophobic, high-barrier, and biodegradable packaging materials. By exploring the impact of ascorbic acid coagulation bath treatment and plasma-enhanced chemical vapor deposition (PECVD) on the properties of RC films, we found that the coagulation bath treatment facilitated the organized reconfiguration of cellulose chains, while PECVD applied a dense SiOx coating on the film surface. The results demonstrated a significant enhancement in water vapor and oxygen barrier properties of the composite film, almost reaching the level of commercial barrier films. Moreover, the composite film displayed exceptional biodegradability, fully degrading in soil within 35 days. Additionally, it showcased impressive mechanical strength, hydrophobic characteristics, and freshness preservation, positioning it as a valuable option for bio-based high-barrier packaging applications.