Search Results (1,219)

Starch and lignin are promising biopolymers for the production of biodegradable biocomposite materials. The possibility of processing starch into thermoplastic materials qualifies it as a starting material for the preparation of thermoplastic packaging films, and the combination with lignin can even out some inherent weak points of starch, such as moisture and water sensitivity, and can add additional features like antioxidant activity. Lignins from herbaceous biomass carry building blocks that are not found in wood lignins and are known for their bioactivity, such as p-coumaric acid or ferulic acid. In this work, a protocol was developed to initially prepare hybrids of wheat starch granules and lignin nanoparticles, which were then plasticized using glycerol in an extrusion process to produce thin films. The lignin-containing thermoplastic starch films showed higher Young’s moduli and less elongation at break compared to neat thermoplastic starch films, while tensile strength remained at the level of the neat films. Thermal stability was slightly increased by lignin addition, and oxygen transmission rates were low for lignin contents as low as 1 wt%. The hydrophobicity of the lignin-containing films increased strongly, and they showed an elevated antioxidant activity over several hours, which was also maintained after 24 h. The preparation of hybrid wheat starch lignin particles was successfully tested for the extrusion of thermoplastic starch films with improved thermomechanical properties, decreased water sensitivity, and prolonged antioxidant activity. Full article

pH-sensitive intelligent films offer a novel strategy for real-time monitoring of food freshness via visible color changes. This study valorizes onion peel powder (OPP), a polyphenol-rich agro-industrial by-product, by incorporating it into cassava starch-based films at three concentrations (1O, 2O, 3O). Increasing OPP content led to significantly higher total phenolic and flavonoid levels, enhancing the films’ antioxidant properties (p < 0.0001). While the films exhibited selective antibacterial effects, pronounced inhibition zones were observed against Pseudomonas aeruginosa and Escherichia coli, two relevant meat spoilage and pathogenic bacteria. The films displayed clear and gradual color shifts from light to dark brown across a wide pH range (1–13), confirming their suitability as pH indicators. When applied as labels in minced beef packaging stored at 4 °C, the films successfully tracked freshness over 13 days. Film color changes were strongly correlated with microbial load and pH variations, accurately flagging spoilage onset. These findings support the potential of cassava starch/OPP films as biodegradable, cost-effective intelligent packaging tools, contributing to food safety, waste reduction, and circular bioeconomy principles. The system provides a practical, non-invasive solution for meat freshness monitoring without requiring instrumentation. Full article

Due to the prevalence of plastic-packaged foods, as well as the need for real-time food monitoring by consumers, reducing plastic pollution is essential for a healthier environment and nutrition. For these reasons, in this work, biodegradable pH-responsive chitosan films enriched with wine lees-derived anthocyanins were produced, and their pH sensitivity was thoroughly evaluated. Optimization of ultrasound-assisted extraction using ethanol/water mixtures as conventional solvents was conducted and the optimal conditions (regarding total anthocyanin content, total phenolic content, and antioxidant activity) were used to perform a screening of extraction with 16 different Natural Deep Eutectic Solvents. Among them, choline chloride: butylene glycol (1:4), at a concentration of 50% v/v in water, demonstrated the highest anthocyanin recovery and was selected for the preparation of the films. The resulting films exhibited an excellent colorimetric response to pH changes, with a color difference (ΔE) exceeding 6.8 at all tested pH values, improved mechanical properties, nearly zero UV permeability, and their antioxidant activity increased by up to 6.1-fold compared to pure chitosan film. Finally, the film was applied in detecting the freshness of pork meat, exhibiting a ΔE of 15.3. The results demonstrate that the developed film is a promising alternative for intelligent, bioactive, and biodegradable food packaging for food applications. Full article

Electrospun alginate nanofibers are emerging as versatile materials for biomedical, environmental, and packaging applications due to their biocompatibility, biodegradability, and functional tunability. However, the direct electrospinning of alginate remains a significant challenge, mainly due to its polyelectrolytic nature, rigid chain structure, and limited chain entanglement. This review provides a comprehensive analysis of recent strategies developed to overcome these limitations, including polymer blending, chemical modification, the addition of surfactants, multi-fluid techniques, and process optimization. We systematically discuss the integration of nanofibers with functional agents such as microorganisms, bioactive compounds, plant extracts, and nanoparticles, highlighting their potential in wound healing, active packaging, bioremediation, and controlled release systems. This review also examines the scalability of alginate electrospinning, summarizing recent patents, industrial solutions, and challenges related to the standardization of the process. Key knowledge gaps are identified, including the need for long-term stability studies, structure–function correlations, green processing approaches, and expansion into novel application domains beyond healthcare. Addressing these research directions will be crucial to unlocking the full potential of alginate nanofibers as sustainable, high-performance materials for industrial use. Full article

Plastic pollution, largely driven by packaging waste, calls for sustainable alternatives. This study investigates biodegradable thermoplastic biocomposites based on PLA, PBS, and PBAT, incorporating 10 wt.% of agro-industrial filler-brewers’ spent grain (BSG) and orange peel (OP) without compatibilization. The biocomposites were produced by melt extrusion followed by thermo-compression. A full factorial design was implemented to assess matrix–filler interactions and compare biocomposites to pure polymer fragments. OP particles, smaller and rougher than BSG, exhibited a higher specific surface area, influencing composite morphology and behavior. The OP slightly plasticized PLA, possibly due to volatile release during processing, whereas BSG increased stiffness in PBS and PBAT. Both fillers reduced mechanical strength, especially in PLA, due to limited interfacial adhesion, and significantly decreased PLA’s thermal stability. The addition of fillers also increased water sorption and modified the sorption kinetics of the three main modes (Langmuir-type, Henry’s law sorption, and water molecule clustering), as well as the values of the half-sorption diffusion coefficients (D₁ and D₂), with notable differences between the OP and BSG linked to their structure and composition. These findings provide a better understanding of structure–property relationships in biodegradable composites and highlight their potential for sustainable packaging and other industrial applications. Full article

Recently, plastic and agricultural waste have gained attention as sustainable alternatives. Despite efforts to recycle these materials, much still ends up in landfills, raising environmental concerns. To optimize their potential, these wastes ought to be transformed into value-added products for diverse industrial applications. This work focused on producing thin composite material films using olive oil solid waste called JEFT and recycled plastic bottles. JEFT was cleaned, dried, and processed mechanically via ball milling to produce nano- and micron-sized particles. Composite films were produced via melt compounding and compression molding with a rapid cooling process for controlled crystallinity and enhanced flexibility. Their density, water absorption, tensile strength, thermal stability, water permeability, functional groups, and biodegradation were comprehensively analyzed. Results indicated that 50% JEFT in recycled plastic accelerated thermal deterioration (42.7%) and biodegradation (13.4% over 60 days), highlighting JEFT’s role in decomposition. Peak tensile strength (≈32 MPa) occurred at 5% JEFT, decreasing at higher concentrations due to agglomeration. Water absorption and permeability slightly increased with JEFT content, with only a 1% rise in water permeability for 50% JEFT composites after 60 days. JEFT maintained the recycled plastic’s surface chemistry, ensuring stability. The findings of this study suggest that JEFT/r-HDPE films show potential as greenhouse coverings, enhancing crop production and water efficiency while improving plastic biodegradation, offering a sustainable waste management solution. Full article

Food is fundamental to human survival, health, culture, and well-being. In response to the increasing demand for sustainable food preservation, chitosan (CS)-based electrospun nanofibers have emerged as promising materials due to their biodegradability, biocompatibility, and inherent antimicrobial properties. When combined with other biopolymers or bioactive compounds, CS-based nanofibers offer enhanced functionality for applications in food packaging, preservation, and additives. This review summarizes recent advances in the fabrication and performance of CS-polymer and CS-inorganic composite nanofibers, with a focus on their mechanical strength, thermal stability, barrier properties, and antimicrobial efficacy. The use of these nanofibers across a range of food categories—including vegetables, fruits, fresh-cut produce, dairy products, meat, seafood, and nuts—is examined. Beyond experimental approaches, the review also explores the growing role of computational simulations in predicting the mechanical strength, barrier performance, antimicrobial activity, and biodegradability of CS-based nanofibers. Key modeling techniques and simulation tools are summarized. Finally, current challenges and future research directions are discussed, underscoring the potential of CS-based electrospun nanofibers as sustainable and multifunctional solutions for modern food packaging. By integrating experimental advancements with computational insights, this review provides a comprehensive and forward-looking perspective on CS-based electrospun nanofibers for food packaging. Full article

This study introduces an innovative strategy for active, biodegradable food packaging through the incorporation of gamma-decalactone (GDL), a natural aromatic compound with antimicrobial properties, into apple-pectin-based edible films. The addition of GDL significantly modified the film structure, resulting in enhanced light barrier properties (the opacity increased from 1.10 to 8.64 a.u./mm), a more porous microstructure (confirmed by SEM), and reduced tensile strength (from 13.84 to 5.68 MPa). The films also exhibited lower water vapour sorption (from 1.45 to 0.80 g/g dry matter (d.m.) and increased gas permeability. FTIR analysis confirmed interactions between GDL and the polymer matrix. The films with GDL added exhibited antimicrobial properties against various microbial species, such as bacteria, yeasts, and moulds. A 5% addition of GDL to the coating completely inhibited the growth of Bacillus subtilis bacteria and Yarrowia lipolytica, reducing the number of yeast cells by 3 log units (after 48 h of culture, from 7.11 ± 0.09 to 4.09 ± 0.27 log CFU/mL) and limiting Monilinia fructicola mycelium growth by 70%. These results highlight GDL’s dual function as a natural aromatic and antimicrobial agent, supporting its potential application in sustainable packaging for perishable foods. Full article

Packaging demand currently exceeds 144 Mt per year, of which >90% is conventional plastic, generating over 100 Mt of waste and 1.8 Gt CO₂-eq emissions annually. In this review, we systematically survey three classes of lignocellulosic feedstocks, agricultural residues, fruit and vegetable by-products, and forestry wastes, with respect to their physicochemical composition (cellulose crystallinity, hemicellulose ratio, and lignin content) and key processing pathways. We then examine fabrication routes (solvent casting, extrusion, and compression molding) and quantify how compositional variables translate into film performance: tensile strength, elongation at break (4–10%), water vapor transmission rate, thermal stability, and biodegradation kinetics. Highlighted case studies include the reinforcement of poly(vinyl alcohol) (PVA) with 7 wt% oxidized nanocellulose, yielding a >90% increase in tensile strength and a 50% reduction in water vapor transmission rate (WVTR), as well as pilot-scale extrusion of rice straw/polylactic acid (PLA) blends. We also assess techno-economic metrics and life-cycle impacts. Finally, we identify four priority research directions: harmonizing pretreatment protocols to reduce batch variability, scaling up nanocellulose extraction and film casting, improving marine-environment biodegradation, and integrating circular economy supply chains through regional collaboration and policy frameworks. Full article

In recent years, food waste management has become one of the key challenges faced by modern society. The significant ecological footprint left by this type of waste can be mitigated through proper valorization. Directing food waste towards the production of biopolymers has attracted considerable attention from researchers. Plant- and animal-based by-products from the food industry are the valuable materials which can be utilized for the production of biopolymer-based films. Although the use of food waste in biopolymer film production holds great potential, various factors such as the type of source and extraction methods significantly affect the physicochemical properties of the films. With the addition of various compounds that enhance their antioxidant and antimicrobial effects, these films can prolong the freshness and safety of packaged products, making them comparable to plastic derived from fossil fuels. This review highlights the potential of biopolymers from food waste for the production of biopolymer-based films and the possibilities of their modification in order to improve their properties for use in the food packaging industry. Full article

Improving the end-of-life performance of polylactic acid (PLA) for food packaging requires strategies that enhance biodegradability, solubility, and dispersibility without compromising essential material properties. PLA-based films were produced by melt extrusion using polyvinylpyrrolidone (PVP) as a hydrophilic modifier, aiming to enhance the water uptake and affinity of PLA, which may potentially lead to faster environmental degradation. Two PVPs with distinct molar masses at varying concentrations were used to investigate their effects on the structural, thermal, mechanical, optical, and barrier behavior of the films. Thermal analysis revealed a slight depression in glass transition temperature, more evident in blends with low-molecular-weight PVP10, indicating increased chain mobility and partial miscibility. A two-step degradation process with extended thermal decomposition profiles was observed upon the inclusion of PVP. SEM and ATR-FTIR analyses confirmed enhanced dispersion and non-covalent interactions in PVP10-based blends, in contrast to the pronounced phase separation and micro-voids observed in PVP40-based systems. Mechanically, films containing 5 and 10 wt.% of PVP10 retained tensile strength and stiffness, whereas PVP40 led to embrittlement. Optical properties were modified by increasing the PVP content, resulting in greater opacity and color differences, which potentially offer benefits for light-sensitive packaging. Altogether, PLA films containing 5 and 10 wt.% of PVP10 demonstrated the most favorable balance between water affinity-oriented design and packaging-relevant performance. Full article

The outlook for biobased plastics in packaging applications is increasingly promising, driven by a combination of environmental advantages, technological innovation, and shifting market dynamics. Derived from renewable biological resources, these materials offer compelling benefits over conventional fossil-based plastics. They can substantially reduce greenhouse gas emissions, are often recyclable or biodegradable, and, in some cases, require less energy to produce. These characteristics position biobased plastics as a key solution to urgent environmental challenges, particularly those related to climate change and resource scarcity. Biobased plastics also demonstrate remarkable versatility. Their applications range from high-performance barrier layers in multilayer packaging to thermoformed containers, textile fibers, and lightweight plastic bags. Notably, all major fossil-based packaging applications can be substituted with biobased alternatives. This adaptability enhances their commercial viability across diverse sectors, including food and beverage, pharmaceutical, cosmetics, agriculture, textiles, and consumer goods. Several factors are accelerating growth in this sector. These include the increasing urgency of climate action, the innovation potential of biobased materials, and expanding government support through funding and regulatory initiatives. At the same time, consumer demand is shifting toward sustainable products, and companies are aligning their strategies with environmental, social, and governance (ESG) goals—further boosting market momentum. However, significant challenges remain. High production costs, limited economies of scale, and the capital-intensive nature of scaling biobased processes present economic hurdles. The absence of harmonized policies and standards across regions, along with underdeveloped end-of-life infrastructure, impedes effective waste management and recycling. Additionally, consumer confusion around the disposal of biobased plastics—particularly those labeled as biodegradable or compostable—can lead to contamination in recycling streams. Overcoming these barriers will require a coordinated, multifaceted approach. Key actions include investing in infrastructure, advancing technological innovation, supporting research and development, and establishing clear, consistent regulatory frameworks. Public procurement policies, eco-labeling schemes, and incentives for low-carbon products can also play a pivotal role in accelerating adoption. With the right support mechanisms in place, biobased plastics have the potential to become a cornerstone of a sustainable, circular economy. Full article

This study investigated the development of biocomposites for use as packaging and film in everyday applications. The utilization of rice flour (RF) as a cheap natural filler in the production of polybutylene succinate (PBS) biocomposites has been shown to reduce environmental issues caused by non-biodegradable plastic waste. The effect of rice flour content on the morphology and properties of PBS and RF biocomposites was comprehensively evaluated. Different amounts of rice flour were considered (0, 10, 20, 30, 40, and 50 phr), and a silane coupling agent and epoxidized natural rubber (ENR-50: 1 phr) were used as interfacial agents to improve compatibility between the matrix (PBS) and filler (RF). The PBS/RF biocomposites were prepared using a two-roll mill and shaped into test specimens and films using a compression molding machine. Batches of the composites containing different amounts of RF were prepared in accordance with the standards, and their morphology and properties, including mechanical properties, density, water absorption, and soil burial degradation, were evaluated. The results revealed that the incorporation of silane-treated RF filler and ENR-50 compatibilizer led to notable improvements in mechanical properties, particularly in tensile modulus, flexural strength, flexural modulus, and hardness. A significant improvement in mechanical performance was observed as the RF content increased, with the highest value recorded at the 50 phr loading. The enhancements observed in the composite properties are due to the inherent rigidity of the RF filler and its improved compatibility with the PBS matrix, which together contribute to a stronger and more efficient material. Additionally, the percentage of water absorption in the PBS/RF biocomposites increased with higher RF content. The results from the soil burial test demonstrated that increasing the RF content positively influenced the biodegradability of the PBS/RF biocomposite materials. Full article

In this study, a bio-nanocomposite integrating calcium caseinate, modified starch, and bentonite nanoclay was formulated and synthesized into film form via solution casting. Glycerol was incorporated for plasticization, and polyvinyl alcohol (PVA) was used to enhance the structural and chemical attributes of the material. The addition of PVA and bentonite notably improved the mechanical strength of the casein-based matrix, showing up to a 30% increase in tensile strength compared to similar biopolymer formulations. Water vapor permeability was significantly reduced when compared to previously reported casein–starch formulations, evidencing the barrier-positive effects of bentonite nanostructures. The microbial analysis confirmed that the quantity of bacterial colonies remained within permissible levels for non-antimicrobial biodegradable films; however, further antibacterial evaluations are advised. Biodegradability testing showed a consistent degradation trend, with full disintegration extrapolated to occur around 13 weeks under natural soil conditions. This study offers exploratory insight into the development of functional and biodegradable films using biopolymer blends and nanoclay suspensions, highlighting their potential in sustainable food packaging applications. Full article

Biodegradable poly(lactic acid) (PLA)/poly(ε-caprolactone) (PCL) composite films were prepared with a compatibilizer (tributyl citrate, TBC) using a solvent casting method. Incorporation of 5% TBC (w/v, of PCL weight) improved tensile strength and elongation at break (21.93 ± 2.33 MPa and 21.02 ± 1.54%, respectively) and reduced water vapor permeability (from 0.12 ± 0.01 to 0.098 ± 0.01 g·mm·m²·h·kPa), indicating improved compatibility between PLA and PCL. Staphylococcus aureus phage PBSA08 demonstrated rapid and persistent bacteriolytic activity for up to 24 h, suggesting its potential as a promising antibacterial biological agent. To impart antibacterial properties to the developed PLA/PCL/TBC film, PBSA08 was loaded into sodium alginate (SA) and coated on the film surface. The optimal composition was 3% (w/v) SA and 3% (w/v) glycerol, which exhibited suitable dynamic behavior as a coating solution and excellent adhesion to the film surface. The phage-coated antibacterial films demonstrated progressive and significant inhibition against S. aureus starting from 10 to 24 h, with controlled phage-release properties. Overall, the developed active film might exert sustained and remarkable antibacterial effects through controlled release of biological agents (phage) under realistic packaging conditions. Full article