Food packaging is one of the most commonly used materials today due to its affordability and convenience. However, this type of packaging is challenging to handle after use, leading to significant environmental waste since it is often made from petrochemical polymers that take a long time to decompose. Polyvinyl alcohol (PVA) is a low-cost, safe, and biodegradable polymer with high potential for food packaging, offering a solution to waste issues in the polymer industry. However, its limited hydrophilicity, bactericidal properties, and poor performance in humid conditions hinder its practicality. Enhancing the mechanical properties and water resistance of PVA-based composite films can significantly improve their applicability, particularly in food packaging. In this study, nanocomposite films based on PVA were reinforced with nanocellulose fiber (CNF) and Ag nanoparticles (AgNPs), and cross-linked using citric acid (CA) through the film casting method. The incorporation of CNF and AgNPs improved the structural integrity and thermal stability of the film, while CA crosslinking significantly enhanced water resistance and mechanical properties. The (PVA/CNF/Ag)-CA film exhibited the highest tensile strength (89.44 MPa), Young's modulus (3.29 GPa), and water contact angle (similar to 90 degrees), alongside the lowest water absorption (78.6 %) and a reduced water vapor transmission rate of 6.62 g x h(-1) x m(-2). Compared to pure PVA film, the resulting crosslinked nanocomposite films showed a 32.3 % increase in modulus and a 22.64 % increase in tensile strength. Additionally, the (PVA/CNF/Ag)-CA film exhibited higher thermal stability with 13 % more residue content than uncrosslinked counterparts, reduced moisture absorption, minimal swelling, and water insolubility. However, the CA crosslinking process promoted AgNP aggregation, reducing the antibacterial activity of the (PVA/CNF/Ag)-CA film against Staphylococcus aureus and Escherichia coli, and slowed down its biodegradation in soil. Nevertheless, after seven days of storage under both aerobic and anaerobic conditions, the nanocomposite coatings effectively minimized mass loss and microbial growth on fresh chili peppers. These results highlight the synergistic contribution of CNF/Ag reinforcement and CA crosslinking in enhancing the mechanical strength, thermal stability, and water resistance of PVA-based films for potential food packaging applications.

Development of bio-based active packaging systems for lipid stabilization presents critical importance in preserving lipid integrity and ensuring food safety. Zein/citric acid (Z/CA) composite films containing grape seed ethanol extract (GSEE) (0-8% w/w) were prepared by the solvent casting method. The structural, functional, and environmental properties of the films, including physical and chemical properties, mechanical properties, antioxidant capacity, antibacterial activity, oxidation inhibition effect, and biodegradability, were comprehensively characterized and evaluated. Progressive GSEE enrichment significantly enhanced film thickness (p < 0.05), hydrophobicity, and total phenolic content, while increasing water vapor permeability by 61.29%. Antioxidant capacity demonstrated radical scavenging enhancements of 83.75% (DPPH) and 89.33% (ABTS) at maximal GSEE loading compared to control films. Mechanical parameters exhibited inverse proportionality to GSEE concentration, with tensile strength and elongation at break decreasing by 28.13% and 59.43%, respectively. SEM microstructural analysis revealed concentration-dependent increases in surface asperity and cross-sectional phase heterogeneity. Antimicrobial assays demonstrated selective bacteriostatic effects against Gram-negative pathogens. Notably, the composite film containing 6 wt% GSEE had a remarkable restraining effect on the oxidation of lard. The soil degradation experiment has confirmed that the Z/CA/GSEE composite film can achieve obvious degradation within 28 days. The above results indicate that the Z/CA/GSEE composite material emerges as a promising candidate for sustainable active food packaging applications.

The growing demand for sustainable and environment-friendly materials has driven extensive research on biopolymers for applications in agriculture, food science, and environmental remediation. Among these, nanocellulose-hydrogel hybrids (NC-HHs) have gained significant attention as an innovative class of bio-based materials that uniquely combine the remarkable physicochemical properties of nanocellulose with the functional versatility of hydrogels. These hybrids are characterised by exceptional water retention, mechanical strength and biodegradability, enabling advances in precision agriculture, smart food preservation and contaminant remediation. This review provides a comprehensive understanding of the synthesis, properties, and multifunctional applications of NC-HHs, emphasising their innovative role in sustainability. In agriculture, NCHHs enhance soil moisture retention, support plant growth, and serve as carriers for controlled-release fertilizers, optimizing water and nutrient use efficiency. In the food industry, they enable intelligent packaging solutions that extend shelf life, monitor food freshness, and inhibit microbial growth. Additionally, NC-HHs present groundbreaking strategies for environmental remediation by effectively immobilizing pollutants in water and soil. Beyond summarizing recent advances, this review presents an in-depth mechanistic perspective on the interactions between NC and HH, critically evaluating their structure-property relationships, functional adaptability and application-specific performance. By integrating recent advances in nanocellulose functionalisation, polymer chemistry and the development of responsive hydrogels, this review critically examines the key technological innovations and future prospects of NC-HHs, underscoring their transformative potential in addressing global challenges related to food security, environmental sustainability, and sustainable agricultural practices.

This study focuses on the development of polyvinyl alcohol-chitosan-tragacanth gum composite films enriched with rosehip extract and seed oil for the packaging of active foods. The films were tested for their antioxidant activity, transparency, biodegradability, water vapor permeability and effectiveness in preserving sweet cherries under seasonal high temperature conditions. The addition of tragacanth, rosehip extract and rosehip seed oil significantly influenced the mechanical properties by increasing elongation at break and tensile strength. Films enriched with rosehip seed oil effectively reduced weight loss and preserved the sensory properties of the cherries, while films based on rosehip extract exhibited superior antioxidant properties with increased free radical scavenging activity. Biodegradability tests showed that all films degraded under soil conditions, with the rate of degradation depending on the concentration of tragacanth gum. The water vapor permeability results showed that the addition of rosehip extract and seed oil significantly reduced the water vapor permeability and improved the barrier properties of the films. Preservation tests showed that these films minimized titratable acidity, oxidative stress and moisture loss, effectively extending the shelf life of sweet cherries under highly stressful conditions. These results highlight the potential of rosehip-enriched biopolymer films as a sustainable and environmentally friendly packaging alternative to extend the shelf life of perishable fruits.

This work focused on the development of a hydrophobic biocomposite film reinforced with natural jute fiber. The biocomposite was made using a blend of chitosan and guar gum and reinforced with varying concentration of jute fiber followed by casting and air drying in petri dishes. Microscopic analysis of the cross-sectional structure of the films revealed a dense, compact morphology and FTIR result shows evidence of chemical interaction of the composite components. The inclusion of Jute fiber was found to increase the water repellant capacity of the films. The film water vapor permeability (WVP) was reduced from 4.1 x 10(-10) (g/m(2)center dot day center dot kPa) to 1.2 x 10(-10) (g/m(2)center dot day center dot kPa) with addition of jute fiber. Although the presence of Jute affects color properties of the films, it significantly improved their ability to block UV-Vis light. The tensile strength and elongation at break of CS/GG 0 % JT film, CS/GG/1 % JT, CS/GG/1.25 %JT and, CS/GG/1.5 % JT film was turned out to be (38.4 MPa, 45.3 MPa, 51.6 MPa and 60 MPa), (15.33 %, 17.66 %, 21.33 % and, 14 %) respectively. Notably, an increased in the DPPH radical scavenging assay was also observed from similar to 87 % in CS/GG composite to 99.4 % (1 % JT film), 99.66 % (1.25 %JT film) and 99.83 % for 1.5 % JT reinforced films respectively. Furthermore, all films showed excellent antimicrobial activity against the foodborne pathogen Escherichia coli and Fusarium oxysporum fungi highlighting their potential as active food packaging material. Signs of biodegradation were observed following four month of soil burial test, confirming the environmental sustainability of the produced biocomposite film.

Poly(butylene adipate-co-terephthalate) (PBAT) and graphene oxide (GO) nanocomposite films were prepared by extrusion to evaluate their potential as films for food packaging. The films were prepared with contents of 0.05, 0.1, and 0.25% in mass of GO by solid-solid deposition methodology. It was verified that GO did not modify the hydrophobicity and crystallinity degree of PBAT. The reduction of molecular weight due to GO incorporation was verified, and it could be the main reason for the observed decrease in tensile strength and increase in elongation. The nanofiller permitted ultraviolet blocking, thermal stability, and oxygen barrier improvements without compromising film visibility. Compared to the neat PBAT film, the oxygen permeability coefficient was reduced by 13.6% for PBAT/GO0.25. The elongation and tenacity were also improved by 90% and 33%, respectively, for the highest concentration of GO (0.25%). Besides, GO at 0.25% accelerated the mineralization rate of PBAT in soil, probably due to the lower molecular weight of nanocomposites in relation to the neat polymer. The preliminary information obtained in this work indicates that the level of PBAT hydrolytic degradation during the extrusion process was not high enough to avoid its application in food packaging because the obtained thermal, mechanical, and ultraviolet (UV) barriers still indicate an exciting balance of properties for this purpose, which can even be improved with future research.

Agricultural biomass is a sustainable source for developing biodegradable film to address mounting plastic perils. This study aims to investigate the influence of CaCl2 concentration on the properties of lignocellulose-based biodegradable film produced from oat straw biomass. Lignocellulose is extracted from oat biomass, and a green technique is employed to solubilize it in ZnCl2 solution and crosslinked with varying CaCl2 concentrations (200 mM-800 mM) to make films. The films containing 800 mM CaCl2 concentration demonstrated the lowest moisture content (12.81 f 0.81 %), water solubility (43.91 f 0.42), water vapor permeability (4.96 f 0.14 x 10-11 gm- 1s-1Pa- 1), visible light transmittance (53.27 f 0.69 %), and moisture absorption (42.42 f 1.32 %). The tensile strength has increased remarkably from 4.24 f 0.76 to 17.24 f 3.68 MPa due to increased CaCl2 concentration from 200 mM to 800 mM. They degraded up to 83 % in soil with 20 % moisture after 28 days. Overall, films made of lignocellulose from oat straw biomass films demonstrate high strength and moisture barrier capabilities, rendering them suitable for use as food packaging materials.

Bio-active packaging films from cellulose acetate incorporated with cypress essential oil (Cyp) have been developed. Thus, cellulose acetate (CA), which is a biodegradable and renewable polymer has been used as an alternative to petroleum-based polymers. Cellulose acetate films were prepared via a solvent casting method incorporating 0, 10, 30, and 60% (w/w) of Cyp. The purpose was to evaluate the possible changes caused by the Cyp on the properties of the packaging films. Different methods and technics have been used to characterize these films. The antibacterial and antioxidant properties of the films were also analyzed. FTIR and XRD analysis indicated that Cyp was homogenously distributed in the films. Meanwhile, TGA analysis demonstrated that the addition of Cyp had an impact on thermal-oxidative properties of the films. The CA/Cyp films showed excellent biodegradability in soil after 60 days, with a percentage loss of 87.07% by mass, and improved mechanical properties with tensile strength and elongation-at-break of 8.1 +/- 0.2 MPa and 16.6 +/- 0.2%, respectively. Water absorption and water solubility values for CA/Cyp films ranged from 76.62 +/- 0.91% to 21.95 +/- 0.57% and from 1.29 +/- 0.35 to undetectable levels, respectively. The results displayed that antibacterial activity against Escherichia coli and Staphylococcus aureus increased as the percentage of Cyp increased in the cellulose acetate films. Moreover, the free radical scavenging activity of cellulose acetate films was improved by increasing the Cyp concentration. These results indicate that cellulose acetate films containing a low-cost essential oil like Cyp have potential for use as active packaging for foods.

The pervasive use of petroleum-based food packaging has caused significant ecological damage due to their unsustainability and non-biodegradability. Polysaccharide-based biodegradable materials are promising alternatives, but low hydrophobicity and functional properties limit their practical applications which can be overcome by incorporation of phytochemical(s). Therefore, by leveraging the strong antioxidant and antibacterial potential of pterostilbene (PTB), we have developed PTB nanoemulsion (NE) incorporated chitosan/sodium alginate (CS/SA) film for food packaging applications. The PTBNE was prepared by high pressure homogenization and characterized for particle size distribution and morphology via DLS, TEM and AFM. The PTBNE CS/SA film was developed by solvent casting method and demonstrated improved mechanical, optical, water resistance and oxygen barrier properties as compared to native CS/SA film. The films were characterized via SEM, 3D optical profilometry, FTIR, XRD and TGA analysis to assess morphological and structural variations. Notably, incorporation of PTBNE in CS/SA matrix significantly enhanced the antioxidant and antibacterial potential of film along with biocompatibility in fibroblast cells. The developed PTBNE CS/SA film demonstrated comparable results with polythene in post harvested shiitake mushroom preservation up to 10 days with rapid soil degradation. Overall, the findings suggested that PTBNE CS/SA film can be a promising alternative to conventional petroleum-based packaging materials.

The increasing issue of plastic waste necessitates improved solutions, and biodegradable food packaging is a promising alternative to traditional plastic. In this study, we prepared packaging films using cassava starch (CV), chitosan (CT) and carboxymethyl cellulose (CMC), with glycerol as a plasticizer. However, these films require modifications to enhance their mechanical properties. Therefore, we modified the films by adding vanillin as the crosslinking agent and gingerol extract stabilized silver nanoparticles. The films were fabricated using the filmcasting method and characterized by FTIR, XRD, SEM, TGA, mechanical property test, biodegradability test, antibacterial test and food packaging evaluation test. Among these films, CT/CV/V/CMC/Gin-AgNPs1 exhibited superior mechanical properties and demonstrated excellent anti-bacterial property both for gram-positive (S. aureus) and gram-negative (E. coli) bacteria and biodegradability, losing over 50% of its weight after 21 days of burial in soil and effectively preserved grapes at 4 degrees C for 21 days.