The scale of the problem the review addresses is staggering. Roughly one-third of global plastic production goes into food and beverage packaging, and much of it ends up in landfills. Middle- and low-income countries generate nearly two-thirds of the world’s plastic waste, compounding waste-management challenges in regions with the fewest treatment infrastructure. Despite decades of recycling campaigns, only about 9 percent of plastic waste is ever recycled. Meanwhile, the chemicals embedded in plastic packaging pose direct health concerns. Bisphenol A, a common component of polycarbonate containers, and phthalates used as plasticizers can migrate into food and act as endocrine disruptors, with documented links to reproductive toxicity and altered neurodevelopment. Additives released as packaging degrades also feed the growing burden of microplastics, which humans are estimated to consume at rates of 203 to 332 particles per person, with children facing disproportionate risk.

Natural fibers, drawn from plants, animals, and even minerals, offer an alternative built on renewability and biodegradability. The review classifies them carefully: bast fibers such as flax, jute, hemp, and ramie come from plant stems and deliver high tensile strength thanks to cellulose-rich, well-organized microfibrillar structures. Leaf fibers including pineapple, sisal, and abaca provide stiffness and reinforcement potential. Seed and fruit fibers like cotton, coir, and kapok serve the textile industry, while agricultural residues such as bagasse, rice husk, wheat straw, and banana pseudostems carry the added appeal of waste valorization, converting low-value byproducts into functional materials without dedicated cultivation. Animal-derived fibers and marine polysaccharides round out the palette, and mineral fibers like glass and ceramic are acknowledged mainly to contrast with their non-biodegradable, industrially specialized nature.

The technical heart of the review lies in its comparative assessment of how these fibers actually perform. Cellulose-rich materials can achieve excellent oxygen-barrier properties under dry conditions because their dense hydrogen-bonded networks block molecular transport. But the same hydrophilic chemistry that creates those bonds makes cellulose vulnerable to humidity: water absorption causes swelling, increased molecular mobility, and collapsed barrier performance at elevated relative humidity. Flax and hemp deliver strong mechanical reinforcement for semi-rigid structures but demand compatibilization when moisture exposure is expected. Jute and sisal provide good strength at low cost for molded trays, while agricultural-waste fibers suit sustainable, low-cost films and molded packaging, provided feedstock variability is controlled. The authors are emphatic that no single fiber wins on every criterion; selection must be application-specific, weighing mechanical loading, moisture exposure, barrier needs, processing route, food-contact safety, and end-of-life pathway together.

Modification strategies form the second pillar of the analysis. Alkali treatment removes hemicellulose, lignin, waxes, and surface impurities, increasing roughness and interfacial adhesion, though excessive exposure damages cellulose chains and generates wastewater. Silane coupling, acetylation, esterification, and grafting reduce surface hydrophilicity. Hydrophobic coatings, crosslinking, and multilayer architectures improve moisture resistance, and nanocellulose incorporation delivers striking gains: the review’s quantitative tables show a cellulose nanofibril, lignin, and tea-polyphenol composite film reaching 230.7 megapascals of tensile strength with oxygen permeability as low as 1.69 times ten to the minus sixteen square centimeters per meter per second per pascal. Starch films plasticized with epoxidized soybean oil oligomers, and oil-palm empty-fruit-bunch fibers treated with sodium hydroxide up to an optimum near ten weight percent, illustrate how different chemical routes achieve comparable improvements through fundamentally different mechanisms. Yet every modification carries trade-offs: added chemicals, energy, cost, and potential migration concerns that can erode the sustainability advantage.

Beyond passive materials, the review highlights active and intelligent packaging as a frontier where natural fibers genuinely shine. Electrospun nanofiber membranes can encapsulate essential oils, plant extracts, and antioxidants, enabling controlled release at the food interface. Bioactive jute fibers loaded with grape pomace antioxidants, biodegradable antimicrobial zein fibers, orange-juice-processing waste films reinforced with cellulose nanofibers and nettle essential oil, and anthocyanin-containing films that change color in response to pH shifts all demonstrate how structural fibers and functional additives can act synergistically. The fiber matrix provides mechanical integrity and a diffusion-regulating carrier; the bioactive compound supplies antimicrobial and antioxidant action. Controlled-release design matters enormously, since excessive loading can cause phase separation, off-odors, sensory changes, and uncontrolled migration, while insufficient release fails to protect the food.

Food-contact safety receives perhaps the most rigorous treatment. The authors stress that biodegradability proves nothing about safety. Natural fibers may carry agricultural contaminants, processing residues, and modification byproducts. Recycled cellulose streams can harbor inks, adhesives, mineral oils, and biocides from previous service lives, and bacterial growth and survival studies have found microbial loads reaching 10.8 log ten colony-forming units per milliliter in recycled-fiber secondary packaging. Per- and polyfluoroalkyl substances, historically used for grease resistance, have been detected in packaging from both virgin and recycled feedstocks, prompting regulatory phase-outs that make PFAS-free barrier strategies essential. Nanomaterial migration, residual solvents from electrospinning, and antimicrobial-agent release all demand standardized testing under realistic time-temperature conditions, with the European Union’s Regulation 1935/2004 and good manufacturing practice rules under Regulation 2023/2006, alongside U.S. Food and Drug Administration provisions, framing the compliance landscape.

The review’s distinctive contribution is its insistence that materials science alone cannot deliver sustainable packaging. Consumer data show 66 percent of the global population expressing environmental awareness, 71 percent shifting toward sustainable practices, and 58 percent actively reducing food and packaging waste, yet a gap persists between perception and purchase in the food category, suggesting trust or market-options deficits. Eco-labelling, green branding, and standardized traffic-light labels can guide choices. Corporate sustainability reporting built on triple-bottom-line principles increasingly drives adoption. Life-cycle assessment, meanwhile, reveals that environmental superiority is never automatic: cultivation, irrigation, fertilizer use, fiber extraction, chemical treatment, drying, and transport all add burdens, and packaging that fails to protect food may simply shift environmental cost from packaging waste to food waste. The carbon advantage of natural fibers over glass or carbon alternatives, demonstrated in polypropylene composites reinforced with cotton, jute, and kenaf, depends on low-energy processing, renewable energy, and locally sourced residues.

Looking forward, the authors lay out a coordinated roadmap: standardize fiber composition and testing, scale processing from laboratory to continuous production, integrate comprehensive migration and toxicological safety evaluation, validate regulatory compliance for complete packaging systems, design for specific end-of-life pathways, and conduct comparative life-cycle and techno-economic assessments using consistent functional units. They envision expansion beyond food into pharmaceutical packaging, electronics casings, automotive interiors, and construction insulation, with nanotechnology and biocomposite engineering pushing durability, adaptability, and barrier performance toward genuine parity with synthetics. The transition, they conclude, requires collaboration among material scientists, food technologists, manufacturers, recyclers, regulators, and producers, and it demands abandoning single-property optimization in favor of balanced, multifunctional design. Natural fibers will not replace every plastic, but in application-specific systems where renewable feedstocks meet targeted chemistry and verified safety, they are positioned to reshape one of the world’s most polluting industries.

Subject of Research: Natural fiber-based materials for sustainable food packaging as replacements for petroleum-based plastics

Article Title: Recent perspectives on natural Fiber-based materials for sustainable packaging- review

Article References: Gopalan, V., Pitchumani, S. V., Harish Kumar, N., Muralinathan, M., & Rajesh Jesudoss Hynes, N. (2026). Recent perspectives on natural Fiber-based materials for sustainable packaging- review. Results in Chemistry, 30, Article 103869. https://doi.org/10.1016/j.rechem.2026.103869

Image Credits: AI Generated

DOI: 10.1016/j.rechem.2026.103869

Keywords: natural fibers, sustainable packaging, biodegradable materials, cellulose, nanocellulose, food packaging, microplastics, endocrine disruptors, life cycle assessment, active packaging, food-contact safety, plastic pollution

Mycelium-based composites are grown rather than manufactured in the conventional sense. Living fungal hyphae are inoculated onto lignocellulosic substrates, where they colonize the particles and weave them into a coherent, self-binding matrix. After the growth phase, the material is dried and heat-treated, killing the fungus and stabilizing the structure. The result is a foam-like solid that is predominantly organic, compostable, and produced at ambient temperatures, in contrast to the energy-intensive polymerization and molding processes behind expanded polystyrene. Despite a decade of enthusiasm, the field has lacked careful, statistically controlled comparisons of how substrate formulation controls performance—precisely the gap the new study set out to close.

The team, led by Diana S. Ocegueda-Vega, Nelly Flores-Ramirez, and Salomon R. Vasquez-Garcia of the Universidad Michoacana de San Nicolás de Hidalgo, together with colleagues at the Tecnológico Nacional de México in Aguascalientes, produced five P. ostreatus composites labeled S1 through S5. Formulations S1 through S4 varied the proportions and particle sizes of oak wood chips, sawdust, and corn cob, while S5 served as a 100 wt% corn-cob reference. Particle architecture proved to be a decisive variable: scanning electron microscopy showed that the geometry of the underlying particles shaped how the fungal hyphae organized, branched, and consolidated the matrix. Coarse wood chips yielded an open, loosely knit structure, whereas finer particles enabled denser hyphal packing and better mechanical integration.

That microstructural difference translated directly into bulk properties. The sawdust-based formulation, S3, achieved the highest apparent density at 178.0 kilograms per cubic meter and the highest compressive strength at 0.63 megapascals. In contrast, the coarse wood-chip formulation S1, with its more open skeleton, delivered the weakest mechanical performance. For context, these densities sit in the same low range as commercial foam packaging materials, but the strength values remain modest—confirming that current mycelium composites are best suited to low-load protective applications such as cushioning inserts, rather than structural load-bearing roles.

Moisture behavior, a long-standing Achilles heel of fungal materials, received detailed treatment. Static water contact angle measurements on the dried surfaces ranged from 107.7 to 110.7 degrees across all five formulations—values comfortably above 90 degrees that indicate hydrophobic character, likely aided by fungal hydrophobin proteins that coat aerial hyphae. Notably, these contact angles did not differ significantly between formulations, suggesting that surface wettability is largely dictated by the mycelium itself rather than the substrate. However, bulk water absorption after 24 hours told a different story: values spread from 30.6 to 46.6 percent, with statistically significant differences. Dunnett-adjusted comparisons against the corn-cob reference showed that S1 absorbed significantly less water while S3 absorbed significantly more, a finding the authors attribute to differences in pore connectivity and particle porosity.

Surface hardness, measured with a Shore D durometer, spanned 27.6 to 37.7 across the formulations. S1 and S2 fell significantly below the corn-cob reference, whereas S3 and S4 were statistically indistinguishable from it. This gradient again tracks the density trend: harder, more consolidated surfaces come from tighter particle packing and more thorough hyphal colonization. The result gives manufacturers a practical dial—adjusting particle size distribution can shift surface robustness without changing the organism or the growth protocol.

Flexural testing exposed one of the field’s persistent limitations. Three-point bending strengths ranged only from 0.07 to 0.10 megapascals, and Tukey’s all-pairwise comparison detected no statistically significant differences among the formulations. In other words, no substrate recipe in this study meaningfully improved bending resistance, which remains the weakest mechanical attribute of mycelium composites. Interestingly, S4 and S5 did post the highest mean compressive and flexural moduli, indicating that stiffness and strength respond differently to formulation—stiffness can be tuned through substrate choice even when ultimate bending strength cannot, at least not within the ranges explored here.

The statistical framework of the study deserves attention because it strengthens the practical value of the findings. Beyond one-way analysis of variance and Tukey’s honestly significant difference test for all pairwise comparisons, the authors applied Dunnett-adjusted comparisons to test each experimental formulation S1 through S4 specifically against the corn-cob reference S5. This design mirrors what an industrial formulator would actually ask: not which recipe wins overall, but whether a given blend of local residues performs as well as, or better than, a baseline single-substrate material. The answers were property-dependent—no single formulation dominated every metric, underscoring that composite design must be matched to the end-use requirements of the packaging component.

The broader significance lies in waste valorization. Quercus castanea wood residues and corn cobs are abundant, inexpensive, and locally available in many agricultural regions, including central Mexico where the research was conducted. Growing packaging from these streams couples two sustainability gains at once: it diverts lignocellulosic waste from open burning or landfilling, and it displaces petroleum-derived foams that persist for centuries and fragment into microplastics. Because mycelium composites are produced at ambient temperature and pressure and are fully biodegradable, their lifecycle emissions profile contrasts sharply with conventional expanded polystyrene, even before accounting for end-of-life benefits.

Realistic caveats remain, and the authors state them plainly. The composites are appropriate for low-load protective packaging only when shielded from direct or prolonged moisture exposure, since bulk water uptake above 30 percent would degrade cushioning performance over time in wet conditions. Mitigation strategies reported elsewhere in the literature—such as beeswax or natural oil coatings—could extend service envelopes, but were outside the scope of this study. Scaling from laboratory samples to mass production will also demand consistent control of colonization time, humidity, and sterilization. Nonetheless, by quantifying exactly how substrate composition and particle architecture govern density, moisture response, hardness, and mechanical performance, the Mexican team has converted a promising but diffuse concept into an engineerable material platform, bringing grown packaging one measurable step closer to the shipping box.

Subject of Research: Physicomechanical properties of Pleurotus ostreatus mycelium biocomposites made from agroforestry residues for sustainable packaging

Article Title: Physicomechanical properties of Pleurotus ostreatus mycelium biocomposites from agroforestry residues for sustainable packaging

Article References: Physicomechanical properties of Pleurotus ostreatus mycelium biocomposites from agroforestry residues for sustainable packaging. (n.d.). https://doi.org/10.1007/s00289-026-06683-0

Image Credits: AI Generated

DOI: 10.1007/s00289-026-06683-0

Keywords: mycelium composites, Pleurotus ostreatus, sustainable packaging, agroforestry residues, biodegradable materials, lignocellulosic waste, water absorption, mechanical properties, biocomposites, waste valorization, circular economy, Polymer Bulletin