Active packaging: Development and characterization of polyvinyl alcohol (PVA) and nitrite film for pork preservation

Dual-functional Zn@melanin nanoparticles for enhanced antibacterial activity and prolonged fruit preservation

Mitigating food spoilage from microbial infections remains a critical challenge in food preservation. Although Zn2+ ions are used as chemical bactericides, their use alone often requires high doses. A novel nanomaterial, Zn@MNPs, combining photothermal properties with the controlled release of Zn2+, was synthesized through a coordination of Zn2+ with melanin nanoparticles (MNPs) derived from cuttlefish ink. Zn@MNPs were capable of attaching onto the bacterial surfaces, enabling high-efficiency release of Zn2+ under mildly acidic conditions typically associated with bacterial infections. This leads to sustained antibacterial activity, causing bacterial membrane rupture and leakage of intracellular components. Incorporating Zn@MNPs into polyvinyl alcohol (PVA)-based films improved their ability to block UV light and reduce oxygen and water vapor permeability. These films effectively reduced dehydration, preserved nutritional content, and extended fruit shelf life. This study highlights the potential of Zn@MNPs-based PVA films as biodegradable, bioactive packaging materials for enhancing food preservation and safety.

Characterization of γ-CD-MOF-stabilized thymol Pickering emulsion films with enhanced preservation properties for Basa (Pangasius) fish

Maintaining the freshness of perishable foods, especially seafood, is a major challenge due to rapid spoilage. This study developed active packaging films by incorporating thymol-loaded Pickering emulsions stabilized by γ-cyclodextrin metal-organic framework (γ-CD-MOF) into polyvinyl alcohol (PVA). The films were characterized for their physical, mechanical, and barrier properties. FTIR, XRD, and thermal analysis confirmed successful incorporation and good stability. The films exhibited antimicrobial activity against foodborne bacteria. When applied to Basa fish fillets at 4 °C, the films reduced bacterial counts from 9.87 to 6.1 log CFU/g over 18 days and extended shelf life by 6 days. Chemical stability improvements were observed through changes in pH, TBARS, and TVB-N levels. This research offers a promising approach to addressing food spoilage challenges and provides a potential solution for extending the shelf life of highly perishable seafood products through advanced active packaging technology.

Effect of eucalyptus nanofibril as reinforcement in biodegradable thermoplastic films based on rice starch (Oryza sativa): Evaluation as primary packaging for crackers

This study investigated the incorporation of eucalyptus nanocellulose (CNF) into rice starch-based thermoplastic (TPS) films, evaluating the effects of four CNF concentrations (0 %, 2 %, 4 %, and 6 %, w/w) on the physicochemical properties of the films. The analyses included scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), solubility, mechanical properties, optical properties, biodegradability, and application for cookie preservation. Atomic force microscopy (AFM) confirmed good CNF dispersion at 4 %, while higher concentrations caused agglomeration. FTIR analysis revealed effective interactions between CNF and the starch matrix. The TPS + 4 % CNF film showed reductions in water solubility (44 %), solubility in acidic (34 %) and basic (32 %) conditions, water vapor permeability (51 %), and water retention capacity (27 %) compared to pure TPS. Tensile strength increased from 3 MPa (pure TPS) to 6.5 MPa (TPS with 4 % CNF), while elongation at break ranged from 38 % (pure TPS) to 65 % (TPS with 2 % CNF). At 6 % CNF, elongation decreased to 45 %, with increased rigidity. The TPS + 4 % CNF film demonstrated good performance in mechanical strength and water vapor barrier properties, while higher CNF concentrations resulted in stiffer, less flexible films due to restricted polymer chain mobility. Higher CNF concentrations also increased the film's opacity. With 90 % biodegradability after 15 days, the reinforced film showed environmental potential. In cookie preservation, TPS + 4 % CNF demonstrated promising performance, with moisture barrier and texture preservation capabilities comparable to oriented polypropylene (BOPP). The combination of biodegradable primary packaging with non-biodegradable secondary packaging offers an innovative solution for food protection with reduced environmental impact.

Preparation and characterization of polyvinyl alcohol and chitosan composite film with cassia oil encapsulated in β-cyclodextrin and its application in fresh banana

In this study, composite films were developed by encapsulating cassia oil (CO) with β-cyclodextrin through a microencapsulation technique and incorporating it into a chitosan (CS), polyvinyl alcohol (PVA) and glycerol matrix. The primary objective of the film was to inhibit bacterial growth on the surface of fresh bananas and extend their shelf life. Characterization methods were employed to evaluate the physical properties and functionality of the composite films. FTIR, XRD, and SEM analyses demonstrated that cassia oil microcapsules (COM) were uniformly dispersed throughout the film and exhibited excellent compatibility with the matrix. The inclusion of 30 % COM improved the film's UV-blocking properties from 86.15 % to 91.03 %. Additionally, due to its hydrophobic nature, CO significantly reduced the water content to 9.02 % and 10.67 %. Furthermore, the COM enhanced the film's tensile strength from 21.18 MPa to 43.21 MPa, and increased its antioxidant capacity to 36.87 %. The results also indicated that 30 % COM significantly enhanced the film's antimicrobial activity against Escherichia coli and Staphylococcus aureus with inhibition zone diameters of 12.5 mm and 11.5 mm, while maintaining biosafety, as evidenced by unaltered cell survival rates in BEAS-2B and L02 cells. The film containing 30 % COM exhibited excellent preservation capacity for bananas, effectively extending their shelf life. These findings suggest that films containing COM have the potential to replace traditional plastic packaging in practical applications.

Sustainable and biodegradable polymer packaging: Perspectives, challenges, and opportunities

The escalating environmental impact of non-biodegradable plastic waste has intensified global efforts to seek sustainable alternatives, with biodegradable polymers from renewable sources emerging as a promising solution. This manuscript provides the current perspectives, challenges, and opportunities within the field of sustainable and biodegradable packaging. Despite a significant market presence of conventional non-biodegradable petrochemical-based plastics, there is a growing trend towards the adoption of bio-based polymers from renewable resources driven by environmental sustainability and regulatory measures. However, the transition to biodegradable packaging is fraught with challenges, including scalability, cost-effectiveness, technological limitations, comprehensive waste management systems, and infrastructural needs. The manuscript highlights the intrinsic technological challenges and the need for advancements in material science to enhance the performance and adoption of biodegradable packaging. This paper also supply insights into the development and implementation of biodegradable packaging, offering a comprehensive overview of its role in achieving global sustainability goals.

Toward "clean label" processed meat using starter culture and beetroot powder: A case-study in restructured cooked ham

This study evaluated the effects of the combination of beet powder, starter culture, and sodium erythorbate as a curing agent on the chemical and microbiological characteristics of restructured cooked ham during cold storage. Five treatments were developed: the positive control group (COP) with the addition of nitrite and sodium erythorbate, negative control treatment (CON) with the addition of sodium erythorbate; ham added with beet powder (AP), ham added with beet powder and starter culture (APC), ham added with beet powder, starter culture, and sodium erythorbate (APCE). The ham's curing properties and oxidative stability were analyzed for 30 days under refrigeration. The APCE treatment showed better conversion of nitrate to nitrite at time 0 (46.6 mg/kg). The COP sample showed higher residual nitrite content at time 0 (73.1 mg/kg) and nitrosohemochrome pigment (35.67 ppm). Combining beet powder with the commercial starter culture and sodium erythorbate in the formulation of restructured cooked hams positively affected the control of lipid and protein oxidation, making it an alternative to commercial sodium nitrite. PRACTICAL APPLICATION: Beetroot and arugula powders are added to the restructured cooked ham to prepare a clean-label meat product without sodium nitrite. The effects of starter culture and sodium erythorbate are also evaluated. .

Green and renewable thermoplastic polyvinyl alcohol/starch blend film fabricated by melt processing

In this study, the PVA/starch blend films were prepared by dry melting method. The microstructure showed that the starch existed in the continuous PVA matrix in granular structure. When the amount of starch was 30 wt%, the tensile strength increased from 12.8 to 14.7 MPa, and the elastic modulus increased from 15.4 to 20.5 MPa, and the water absorption increased by about 2 %. The addition of starch increased the Tmax by 8.1-29.64 °C compared to pure PVA. Considering the mechanical, hydrophilic and optical properties of the blend films, PVA/starch at 7:3 was the most promising packaging material. Notably, the blend films exhibit great reusability and renewability. Overall, these findings highlight the potential of PVA/starch blend films as environmentally friendly materials with enhanced properties.

Co-encapsulation of probiotic Lactiplantibacillus plantarum and polyphenol within novel polyvinyl alcohol/fucoidan electrospun nanofibers with improved viability and antioxidation

Polyvinyl alcohol (PVA)/fucoidan (FUC) blend nanofibers were systematically fabricated to co-encapsulate probiotic Lactiplantibacillus plantarum 69-2 (LP69-2) and four kinds of polyphenols by electrospinning for the first time. Scanning electron microscopy showed that some areas of PVA/FUC nanofibers encapsulated with LP69-2 were locally broadened. Attenuated total reflectance-Fourier transform infrared spectroscopy and X-ray diffraction suggested that LP69-2 and polyphenol were successfully encapsulated in PVA/FUC electrospun nanofibers. Thermogravimetric analysis revealed that the addition of LP69-2 and polyphenol enhanced the thermal stability of nanofibers. Moreover, the incorporation of FUC and polyphenol significantly increased the ABTS+ and DPPH radical scavenging ability of PVA nanofibers (P < 0.05). Notably, PVA/FUC/LP69-2/DMY nanofibers displayed the highest DPPH radical scavenging ability. After 21 d, these nanofibers loaded with polyphenols could maintain viability of LP69-2 over 7 lg CFU/g at 4 °C and the viability of LP69-2 in PVA/FUC/DMY nanofibers was the highest. Overall, the co-encapsulation of probiotic and polyphenol within PVA/FUC electrospun nanofibers increased the viability of probiotics and enhanced antioxidant activity of nanofibers. This study provided unique insights for protecting probiotics and developing novel functional foods with higher probiotics.

Intelligent Biopolymer-Based Films: Promising New Solutions for Food Packaging Applications

The development of biopolymer-based films represents a promising direction in the packaging industry that responds to stringent needs for sustainability, reducing the ecological impact. Traditional fossil-derived polymers present major concerns because of their long decomposition time and their significant contribution to the pollution of the environment. On the contrary, biopolymers such as chitosan, PVA, and PLA offer viable alternatives. This study aimed to obtain an innovative pH indicator for smart packaging using a synthetic non-toxic anthocyanin analogue dye incorporated in bio-based films to indicate meat freshness and quality. The pH-responsive color-changing properties of the dye make it suitable for developing intelligent films to monitor food freshness. The obtained polymeric films were characterized by FT-IR and UV-VIS spectroscopy, and their thermal properties were assessed using thermogravimetric methods. Moisture content, swelling capacity, and water solubility of the polymeric films were also evaluated. The sensitivity of the biopolymer-flavylium composite films to pH variations was studied in the pH range of 2 to 12 and noticeable color variations were observed, allowing the monitoring of the meat's quality damage through pH changes. The pH-responsive films were applied directly on the surface or in the proximity of pork and chicken meat samples, to evaluate their colorimetric response to fresh and spoilt meat. This study can be the starting point for creating more durable packaging solutions leading to a circular economy.

Polyvinyl alcohol/kappa-carrageenan-based package film with simultaneous incorporation of ferric ion and polyphenols from Capsicum annuum leaves for fruit shelf-life extension

Bio-based food packaging materials have elicited growing interests due to their great degradability, high safety and active biofunctions. In this work, by simultaneously introducing the polyphenolic extracts from Capsicum annuum leaves and ferric ion (Fe3+) into the Polyvinyl alcohol/kappa-carrageenan (PVA/κ-carrageenan)-based film-forming matrix, an active package film was developed, with the purpose to improve the food shelf life. The experimental results indicated that the existence of Fe3+ can not only improve the mechanical properties owing to the multiple dynamic coordinated interactions, but also endow the composite films with excellent fire-retardancy. Moreover, the composite films could display excellent UV resistant performance, water vapor/oxygen gas barrier properties and antioxidant activities with the corporation of polyphenols. In particular, the highest DPPH and ABTS radical scavenging capacities for composite film (PC-PLP7 sample) were evaluated to be 82.5 % and 91.1 %, respectively. Higher polyphenol concentration is favorable to the bio-functions of the materials. Benefitting from these features, this novel kind of films with a dense and steady micro-structure could be further applicated in fruit preservations, where the ripening bananas were ensured with the high storage quality. This integration as a prospective food packaging material provides an economic and eco-friendly approach to excavate the high added-values of biomass.