Transparent, UV-blocking, and high barrier cellulose-based bioplastics with naringin as active food packaging materials

A highly transparent cellulose film for shielding ultraviolet and high-energy visible blue light

The ultraviolet (UV) and high-energy visible blue (HEVB) light can cause damage to the eyes and skin. In this study, a cellulose composite film with UV and HEVB light shielding properties was prepared through the incorporation of a shielding agent into a carboxymethyl cellulose (CMC) solution. The shielding agent was synthesized through a Schiff base reaction between vanillin (VA) and 3-aminopropyltriethoxysilane (APS). The composite films exhibited excellent shielding performance against UV and HEVB light and maintained high visible light transmittance. Additionally, the films achieved shielding ratios of 100 % for UV (200 to 400 nm) and 93 % for HEVB (400 to 450 nm), respectively. Even under prolonged UV irradiation, the composite films maintained excellent shielding stability. The composite films exhibited higher performance in blocking UV and HEVB light than commercial shielding films. Moreover, the composite films achieved 100 % antibacterial efficiency against both Staphylococcus aureus and Escherichia coli, even with minimal amounts of the shielding agent. Furthermore, the films exhibited significant improvements in thermal stability, oxidation resistance, and mechanical properties. The multifunctional UV and HEVB shielding films have broad potential applications in food packaging, anti-UV/HEVB radiation display screens, and mobile phone screens.

Unraveling of Poly(lactic acid) (PLA)/Natural Wax/Titanium Dioxide Nanoparticle Composites for Disposable Plastic Applications

The present research is a comprehensive study that developed poly(lactic acid) PLA/natural wax (Wx)/non-functionalized titanium dioxide nanoparticles (TiO2-NF) and PLA/Wx/titanium dioxide nanoparticles functionalized with triethoxysilane (TiO2-F) composites by melt blending. This research systematically investigated their hydrolytic degradation, antibacterial properties, oxygen permeability, and optical transparency. The TiO2-NF or TiO2-F (0.1, 0.5, or 1 wt%) were added to a PLA/Wx (85:15) blend using a Brabender internal mixer at 180 °C. Hydrolytic degradation was carried out in distilled water at 50 °C and an initial pH of 6.2 for 9 months. Changes in weight, morphology, and the rheological behavior of the blends were evaluated at different times during the hydrolytic degradation of the PLA/Wx/TiO2-NF and PLA/Wx/TiO2-F composites. The antibacterial properties of PLA/Wx, PLA/Wx/TiO2-0.1-NF, and PLA/Wx/TiO2-0.1-F were assessed by testing them against both E. coli (Gram-negative) and S. aureus (Gram-positive) bacteria. Their oxygen permeability and optical transparency are comparable to those of LDPE films. These composites, produced by melt blending, show potential for application as disposable plastics, which could significantly impact the fields of materials science and polymer engineering.

Bioactive flavonoids metabolites in citrus species: their potential health benefits and medical potentials

Citrus flavonoids are naturally occurring phytochemicals widely present in the peels and pulps of citrus fruits. They exhibit a wide range of biological activities, including antioxidant, anti-inflammatory, hypoglycemic, lipid-lowering, antimicrobial, and gut-protective effects. These metabolites show great potential in improving metabolic syndromes such as diabetes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular diseases. Additionally, citrus flavonoids have demonstrated significant effects in inhibiting pancreatic lipase activity, regulating lipid metabolism, and enhancing intestinal barrier function. Advances in extraction and purification techniques have further promoted their applications in the fields of food, medicine, and functional materials. This review systematically summarizes the types, bioactivities, and mechanisms of action of citrus flavonoids, providing scientific evidence for their research and development.

Sodium alginate-camellia seed cake protein active packaging film cross-linked by electrostatic interactions for fruit preservation

The evolution of production and lifestyle patterns has led to an increasing demand for multifunctional packaging materials that exceed the capabilities of traditional single-function options, thus driving continuous innovation in the field. In this study, a novel approach is presented, where camellia seed cake protein, derived from camellia seed oil production by-products, is incorporated into sodium alginate to create biobased active packaging films. The antioxidant and UV-shielding properties of the sodium alginate-camellia seed cake protein films are enhanced by the incorporation of camellia seed cake protein. A closely intertwined structure is created between sodium alginate and camellia seed cake protein through electrostatic interactions, resulting in effective water vapor barrier capabilities. Furthermore, the active packaging films exhibit antimicrobial activity against E. coli and S. aureus, providing significant advantages for fruit preservation. This research is essential in delaying fruit spoilage, extending shelf life, and providing new insights into the development of biobased multifunctional food packaging materials.

Comparative Study of Crucial Properties of Packaging Based on Polylactide and Selected Essential Oils

In order to establish the differences in packaging containing various essential oils, polylactide (PLA)-based polymeric films incorporating poly(ethylene glycol) (PEG), clove (C), grapefruit (G), rosemary (R), and tea tree (T) essential oils were obtained and subsequently analyzed. In addition to examining structure and morphology, the polymer films underwent analyses that are particularly important with regard to contact with food. Mechanical and antioxidant properties, water vapor transmission rate (WVTR), and analysis of barrier properties against ultraviolet (UV) radiation, as well as the migration of ingredients into food simulants such as 10% v/v solutions of ethanol, 3% w/v acetic acid solution, and isooctane, were among the critical studies conducted. A comparison of the properties of the obtained materials allowed us to establish that the incorporation of essential oils significantly increases elongation at break and enhances UV barrier properties. In the case of materials containing clove oil and tea tree oil, a reduction in WVTR of about 1 g/m2/h was observed. The migration of the ingredients present in the films filled with clove oil, grapefruit oil, and tea tree oil into the acetic acid solution did not exceed 10 mg/kg, which is an acceptable value according to the European Union restrictions. Taking into account all of the studied properties, it should be stressed that the most promising packaging material is the film filled with clove oil.

Physical and thermal improvement of bioplastics based on potato starch/agar composite functionalized with biogenic ZnO nanoparticles

This study investigated potato starch/agar-based bioplastics' structure, properties, and biodegradability by adding ZnO nanoparticles (NPs) biogenically synthesized using Coriandrum sativum extract. ZnO NPs presented crystalline structure, good optical properties, and a size of 6.75 ± 1.4 nm, which were added at various concentrations (419.66-104.23 ppm) in bioplastics and their presence was confirmed via EDS elemental analysis and X-ray fluorescence. The highest NPs concentration contributed to a smoother surface, while FTIR and Raman analyses suggested interactions between the NPs and functional groups of the biopolymeric matrix. ZnO NPs addition slightly reduced bioplastic transparency but significantly improved UV-A and UV-B blocking capacities. It also increased hydrophobicity, evidenced by a 22 % reduction in water absorption and a 55 % increase in contact angle. Thermogravimetric analysis (TGA) indicated that NPs raised the bioplastic's thermal stability. Mechanical property tests showed that ZnO NPs concentrations had negligible or negative effects probably due to the heterogeneous distribution of NPs, or the non-isotropic characteristic of the bioplastic. Finally, biodegradability assays in seawater and soil revealed over 43.5 % and 66 % degradation after 15 and 28 days, respectively. Therefore, biosynthesized ZnO NPs mainly enhanced the bioplastic's UV-blocking capacity, hydrophobicity, and thermal properties, offering an eco-friendly option for future studies/applications.

Smart conducting polymer innovations for sustainable and safe food packaging technologies

Biofilm formation on food packaging surfaces is a major issue in the industry, as it leads to contamination, reduces shelf life, and poses risks to human health. To mitigate these effects, developing smart coatings that can actively sense and combat microbial growth has become a critical research focus. This study is motivated by the need for intelligent packaging solutions that integrate antimicrobial agents and sensors for real-time contamination detection. It is hypothesized that combining conducting polymers (CPs) with nanomaterials can enhance antimicrobial efficacy while maintaining the mechanical integrity and environmental stability required for food packaging applications. Through the application of numerous technologies like surface modification, CP-nanoparticle integration, and multilayered coating, the antimicrobial performance and sensor capabilities of these materials were analyzed. Case studies showed a 90% inhibition of bacterial growth and a tenfold decrease in viable bacterial counts with AgNPs incorporation, extending strawberries' shelf life by 40% and maintaining fish freshness for an additional 5 days. Moreover, multilayered CP coatings in complex systems have been shown to reduce oxidative spoilage in nuts and dried fruits by up to 85%, while maintaining the quality of leafy greens for up to 3 weeks under suboptimal conditions. Environmental assessments indicated a 30% reduction in carbon footprint when CP coatings were combined with biodegradable polymers, contributing to a more transparent and reliable food supply chain. CP-based films integrated with intelligent sensors exhibit high sensitivity, detecting ammonia concentrations below 500 ppb, and offer significant selectivity for sensing hazardous gases. These findings indicate that CP-based smart coatings markedly enhance food safety and sustainability in packaging applications.

Date seed extract encapsulated-MCM-41 incorporated sodium alginate/starch biocomposite films for food packaging application

In this study, we developed active bio-composite films using a sodium alginate/starch (1:1) matrix incorporating date seed extract encapsulated mesoporous silica (DSE@MCM-41) up to 7.5 wt%. Incorporating DSE@MCM-41 significantly improved the films' properties, enhancing antioxidant efficacy and UV-blocking capabilities. Notably, the films exhibited a 29.5 % increase in tensile strength, a 34.81 % decrease in water absorption, and a reduction in water vapor permeability to 1.76 × 10-8 g m-1.h-1.pa-1 at 5 wt% DSE@MCM-41 concentration. These enhancements, coupled with sustained DSE release, effectively extended the shelf life of black grapes by up to 16 days. These results demonstrate the potential of DSE@MCM-41-incorporated bio-composite films to improve food preservation and extend shelf life, making them suitable candidates for advanced food packaging systems.

Microbial Polysaccharides as Functional Components of Packaging and Drug Delivery Applications

This review examines microbial polysaccharides' properties relevant to their use in packaging and pharmaceutical applications. Microbial polysaccharides are produced by enzymes found in the cell walls of microbes. Xanthan gum, curdlan gum, pullulan, and bacterial cellulose are high-molecular-weight substances consisting of sugar residues linked by glycoside bonds. These polysaccharides have linear or highly branched molecular structures. Packaging based on microbial polysaccharides is readily biodegradable and can be considered as a renewable energy source with the potential to reduce environmental impact. In addition, microbial polysaccharides have antioxidant and prebiotic properties. The physico-chemical properties of microbial polysaccharide-based films, including tensile strength and elongation at break, are also evaluated. These materials' potential as multifunctional packaging solutions in the food industry is demonstrated. In addition, their possible use in medicine as a drug delivery system is also considered.

Hydrophobic, ultraviolet radiation-shielding, and antioxidant functionalities of TEMPO-oxidized cellulose nanofibril film coated with modified lignin nanoparticles

In this study, lignin nanoparticles (LN) and octadecylamine-modified LN (LN-ODA) were utilized as coating materials to enhance the hydrophobic, antioxidant, and ultraviolet radiation-shielding (UV-shielding) properties of a TEMPO-oxidized nanocellulose film (TOCNF). The water contact angle (WCA) of the TOCNF was approximately 53° and remained stable for 1 min, while the modified LN-ODA-coated TOCNF reached over 130° and maintained approximately 85° for an hour. Pure TOCNF exhibited low antioxidant properties (4.7 %), which were significantly enhanced in TOCNF-LN (81.6 %) and modified LN-ODA (10.3 % to 27.5 %). Modified LN-ODA-coated TOCNF exhibited antioxidant properties two to six times higher than those of pure TOCNF. Modified LN-ODA exhibited thermal degradation max (Tmax) at 421 °C, while pure LN showed the main degradation temperature at approximately Tmax 330 °C. The thermal stability of TOCNF-LN-ODA-coated materials remained consistent with that of pure TOCNF, while the crystallinity index of the sample showed a slight decrease due to the amorphous nature of the lignin structure. The tensile strength of TOCNF was approximately 114.1 MPa and decreased to 80.1, 51.3, and 30.3 MPa for LN-ODA coating at 5, 10, and 15 g/m2, respectively.

Compounding one problem with another? A look at biodegradable microplastics

Environmental concerns about microplastics (MPs) have motivated research of their sources, occurrence, and fate in aquatic and soil ecosystems. To mitigate the environmental impact of MPs, biodegradable plastics are designed to naturally decompose, thus reducing the amount of environmental plastic contamination. However, the environmental fate of biodegradable plastics and the products of their incomplete biodegradation, especially micro-biodegradable plastics (MBPs), remains largely unexplored. This comprehensive review aims to assess the risks of unintended consequences associated with the introduction of biodegradable plastics into the environment, namely, whether the incomplete mineralization of biodegradable plastics could enhance the risk of MBPs formation and thus, exacerbate the problem of their environmental dispersion, representing a potentially additional environmental hazard due to their presumed ecotoxicity. Initial evidence points towards the potential for incomplete mineralization of biodegradable plastics under both controlled and uncontrolled conditions. Rapid degradation of PLA in thermophilic industrial composting contrasts with the degradation below 50 % of other biodegradables, suggesting MBPs released into the environment through compost. Moreover, degradation rates of <60 % in anaerobic digestion for polymers other than PLA and PHAs suggest a heightened risk of MBPs in digestate, risking their spread into soil and water. This could increase MBPs and adsorbed pollutants' mobilization. The exact behavior and impacts of additive leachates from faster-degrading plastics remain largely unknown. Thus, assessing the environmental fate and impacts of MBPs-laden by-products like compost or digestate is crucial. Moreover, the ecotoxicological consequences of shifting from conventional plastics to biodegradable ones are highly uncertain, as there is insufficient evidence to claim that MBPs have a milder effect on ecosystem health. Indeed, literature shows that the impact may be worse depending on the exposed species, polymer type, and the ecosystem complexity.

Effect of plasticizers on the rheological properties of xanthan gum - starch biodegradable films

The effect of plasticizers, namely glycerol, sorbitol, and citric acid, on the structural and mechanical properties of biodegradable films obtained from xanthan gum (XG) and starch was studied. The plasticizing effect of glycerol, sorbitol, and citric acid on XG-starch films is justified by the destruction of intermolecular contacts between starch and XG macromolecules and the redistribution of hydrogen bonds in the system as a result of the hydrotropic action of plasticizer molecules. The use of glycerol proved to be the most effective for regulating the deformation of films, while the use of sorbitol to preserve strength. The dependence of the film roughness on the type and concentration of plasticizers was characterized. The smallest values of protrusions on the surface of XG-starch films were found in the presence of sorbitol. Considering the effect of the concentration of plasticizers on the stickiness of the surface of XG-starch films and their structural and mechanical properties, 1.5 % concentration of glycerol, sorbitol and citric acid was determined as optimal.

Transparent, plasticized cellulose-glycerol bioplastics for food packaging applications

Free-standing films have been obtained by drop-casting cellulose-glycerol mixtures (up to 50 wt% glycerol) dissolved in trifluoroacetic acid and trifluoroacetic anhydride (TFA:TFAA, 2:1, v:v). A comprehensive examination of the optical, structural, mechanical, thermal, hydrodynamic, barrier, migration, greaseproof, and biodegradation characteristics of the films was conducted. The resulting cellulose-glycerol blends exhibited an amorphous molecular structure and a reinforced H-bond network, as evidenced by X-ray diffraction analysis and infrared spectroscopy, respectively. The inclusion of glycerol exerted a plasticizing influence on the mechanical properties of the films, while keeping their transparency. Hydrodynamic and barrier properties were assessed through water uptake and water vapor/oxygen transmission rates, respectively, and obtained values were consistent with those of other cellulose-based materials. Furthermore, overall migration levels were below European regulation limits, as stated by using Tenax® as a dry food simulant. In addition, these bioplastics demonstrated good greaseproof performance, particularly at high glycerol content, and potential as packaging materials for bakery products. Biodegradability assessments were carried out by measuring the biological oxygen demand in seawater and high biodegradation rates induced by glycerol were observed.

Cellulose-based biomass composite films for plastic replacement: Synergistic UV shielding, antibacterial and antioxidant properties

With the gradual increase in environmental awareness and the growing demand for food safety, sustainable and environmentally friendly cellulose-based materials have become a promising alternative to petroleum-based plastics. However, in practice, packaging materials prepared from cellulose-based materials still have some unsatisfactory properties, such as monofunctionality, low transparency, and lack of UV shielding, antibacterial or antioxidant properties. Herein, a novel synthetic strategy is proposed in this paper, specifically, tannic acid (TA), a green natural extract with antibacterial and antioxidant properties, is used as a plasticizer and cross-linker, and oxidized cellulose nanocellulose (TOCN) modified with folic acid (FA) grafting is blended with TA, and cellulose-based biomass thin films with ultraviolet (UV) shielding, antibacterial, and antioxidant properties have been successfully prepared by using a simple vacuum-assisted filtration. The experimental results showed that the films could completely block ultraviolet light at wavelengths of 200-400 nm while providing 81.47 % transparency in the visible spectrum, while the introduction of TA conferred excellent antibacterial and antioxidant capabilities with antioxidant activity of up to 95 %, and also resulted in films with excellent mechanical properties. Therefore, this work provides ideas for the design and manufacture of competitive biomass green packaging materials, laying the foundation for future applications in food packaging.

Machine intelligence-accelerated discovery of all-natural plastic substitutes

One possible solution against the accumulation of petrochemical plastics in natural environments is to develop biodegradable plastic substitutes using natural components. However, discovering all-natural alternatives that meet specific properties, such as optical transparency, fire retardancy and mechanical resilience, which have made petrochemical plastics successful, remains challenging. Current approaches still rely on iterative optimization experiments. Here we show an integrated workflow that combines robotics and machine learning to accelerate the discovery of all-natural plastic substitutes with programmable optical, thermal and mechanical properties. First, an automated pipetting robot is commanded to prepare 286 nanocomposite films with various properties to train a support-vector machine classifier. Next, through 14 active learning loops with data augmentation, 135 all-natural nanocomposites are fabricated stagewise, establishing an artificial neural network prediction model. We demonstrate that the prediction model can conduct a two-way design task: (1) predicting the physicochemical properties of an all-natural nanocomposite from its composition and (2) automating the inverse design of biodegradable plastic substitutes that fulfils various user-specific requirements. By harnessing the model's prediction capabilities, we prepare several all-natural substitutes, that could replace non-biodegradable counterparts as exhibiting analogous properties. Our methodology integrates robot-assisted experiments, machine intelligence and simulation tools to accelerate the discovery and design of eco-friendly plastic substitutes starting from building blocks taken from the generally-recognized-as-safe database.

Avocado seed starch utilized in eco-friendly, UV-blocking, and high-barrier polylactic acid (PLA) biocomposites for active food packaging applications

Efficient and effective use of biopolymers, such as starch, has increasingly prompted interest due to the current environmental challenges. However, starch-based composites still show poor ductility along with water and oxygen permeability, which may not meet the requirements for food packaging standards. In this study, modified starch (m-St), isolated from the avocado seed and synthesized with tert-butyl acetoacetate (t-BAA), was embedded into polylactic acid (PLA) to design new eco-friendly composites. The developed biocomposites were found to exhibit high performance with outstanding mechanical properties in conjunction with remarkable light, water vapor, and oxygen blocking features for food packaging applications. PLA/m-St(1:6) 20 wt% composites showed a dramatic increase in elongation at break (EB%) from 3.35 to 27.80 % (about 730 % enhancement) and exhibited remarkable UV-blocking performance from 16.21 to 83.86 % for UVB, relative to pure PLA. Equally importantly, these biocomposites revealed significant improvement in oxygen and water vapor barrier performance by reducing their values from 1331 to 32.9 cc m-2 day-1 (indicating a remarkable reduction of 97.53 %) and 61.9 to 28 g m-2 day-1, respectively. This study can show the great potential of extracting starch from biowaste resources and transforming it into sustainable bio-based composites as a promising solution for food packaging applications.

Sustainable papaya plant waste and green tea residue composite films integrated with starch and gelatin for active food packaging applications

This study explores the sustainable utilization of wastes from a papaya plant (papaya peels (PP), papaya seeds (PS), leaf-stem (PL)) and dried green tea residues (GTR) for the synthesis of bioplastics. The dried GTR were individually blended with each papaya waste extract and then boiled in water to get three composite papaya plant waste-green tea supernatants. Potato starch and gelatin-based functional films were prepared by integrating each with the composite papaya waste-green tea supernatant liquid. This work introduces a dissolved organic matter (DOM) study to the field of bioplastics, with the goal of identifying the organic components and macromolecules inherent in the PW supernatants. When compared with the films prepared solely from papaya waste (PW) supernatants, PW-GTR composite supernatant films prevent UV light transmission with superior antioxidant and mechanical properties. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction spectroscopy (XRD), and atomic force microscopy (AFM) were utilized to characterize the starch and gelatin PW-GTR films. Owing to the exceptional antioxidant, UV barrier, and remarkable biodegradable properties of the starch/PW/GTR and gelatin/PW/GTR composite films, make them ideal for use in food packaging applications.

UV- shielding and antioxidant properties of chitosan film impregnated with Acacia catechu modified with calcium carbonate for food packaging

Acacia catechu contains polyphenolic compounds such as catechin and tannins, which exhibit antioxidant and antimicrobial properties that have the potential to be used in food packaging applications. In this study, chitosan-based (CH) antioxidant films were developed with the incorporation of calcium carbonate (CC) and Acacia catechu (CT). The films were fabricated by the solvent-casting method, and the effects of the different concentrations of Acacia catechu were analyzed. The physicomechanical, antioxidant, and UV shielding properties of the films were determined. The addition of Acacia catechu and calcium carbonate has significantly increased the tensile from 2.30 MPa to 4.95 MPa, respectively, for neat CH and CH/CC/CT-4 film. At the same time, there is a reduction in the elongation at break from 26.75 % in neat CH film to 12.11 % in CH/CC/CT-4 film. The CH/CC/CT-4 film has shown the highest ferric-reducing antioxidant power (FRAP) of 0.440 mg Trolox/g dried weight of the film and 2,2 diphenyl picrylhydrazyl (DPPH) radical scavenging activity of 93.05 %. The UV transmittance of CH/CC/CT-4 film was 0.46 %, the lowest compared to the rest of the fabricated films. These active properties depict that CH/CC/CT-4 film has the potential to be utilized for the packaging of light and oxygen-sensitive food products.

Recent Highlights in Sustainable Bio-Based Edible Films and Coatings for Fruit and Vegetable Applications

The present review paper focuses on recent developments in edible films and coatings made of base compounds from biological sources, namely plants, animals, algae, and microorganisms. These sources include by-products, residues, and wastes from agro-food industries and sea products that contribute to sustainability concerns. Chitosan, derived from animal biological sources, such as crustacean exoskeletons, has been the most studied base compound over the past three years. Polysaccharides typically constitute no more than 3-5% of the film/coating base solution, with some exceptions, like Arabic gum. Proteins and lipids may be present in higher concentrations, such as zein and beeswax. This review also discusses the enrichment of these bio-based films and coatings with various functional and/or bioactive compounds to confer or enhance their functionalities, such as antimicrobial, antioxidant, and anti-enzymatic properties, as well as physical properties. Whenever possible, a comparative analysis among different formulations was performed. The results of the applications of these edible films and coatings to fruit and vegetable products are also described, including shelf life extension, inhibition of microbial growth, and prevention of oxidation. This review also explores novel types of packaging, such as active and intelligent packaging. The potential health benefits of edible films and coatings, as well as the biodegradability of films, are also discussed. Finally, this review addresses recent innovations in the edible films and coatings industry, including the use of nanotechnologies, aerogels, and probiotics, and provides future perspectives and the challenges that the sector is facing.

A novel, robust mechanical strength, and naturally degradable double crosslinking starch-based bioplastics for practical applications

The increasing number of petroleum-based plastics has caused severe environmental pollution, which has attracted great research interest in the development of low-cost, renewable, and degradable starch-based bioplastics. However, developing starch-based bioplastics with robust mechanical strength, excellent water resistance, and thermal resistance remains a great challenge. In this study, we presented a simple and efficient method for preparing high-performance novel starch-based bioplastics with chemical and physical double crosslinking network structures filled with 2,2,6,6-tetramethylpiperidine 1-oxy-oxidized cellulose nanofibers and zinc oxide nanoparticles. Compared with pure starch-based bioplastics, the tensile strength of the novel robust strength starch-based bioplastics increased by 431.2 %. The novel starch-based bioplastics exhibited excellent mechanical properties (tensile strength up to 24.54 MPa), water resistance, thermal resistance, and biodegradability. In addition, the novel starch-based bioplastics could be reused, crushed, dissolved, and re-poured after use. After recycling, the novel starch-based bioplastics could be discarded in the soil to achieve complete degradation within six weeks. Owing to these characteristics, the novel starch-based bioplastics are good alternatives used to replace traditional petroleum-based plastics and have great development prospects.

Effects of antimicrobial nanocomposite films packaging on the postharvest quality and spoilage bacterial communities of mushrooms (Chanterelles)

Poly (lactic acid) (PLA) composite films with the addition of mesoporous silica nanoparticles MSN (0, 2, 4 and 6 wt%) loaded with 10 wt% citral (CIT) were prepared for application in Chanterelles packaging. Composite films with added MSN/CIT showed good mechanical properties, especially 4MSN/CIT/PLA. Changes in physicochemical properties and bacterial flora of Chanterelles during packaging and storage were tested. Compared with CIT/PLA, Chanterelles packed with 4MSN/CIT/PLA showed about 1.62-times lower browning value, 1.53-times lower electrolyte permeability, and 1.83- and 1.78-times lower PPO and POD, respectively, at 12 day. Better physicochemical properties of Chanterelles can be maintained. For bacterial flora changes, Chanterelles packaged with 4MSN/CIT/PLA had more stable flora (p < 0.05) and lower species diversity during storage (p < 0.05), effectively controlling the growth and reproduction of their dominant spoilage bacteria (Enterobacteriaceae spp). In conclusion, the composite membranes obtained by the addition of MSN/CIT to PLA have great potential in the storage of Chanterelles.

Incorporation of bioactive compounds from avocado by-products to ethyl cellulose-reinforced paper for food packaging applications

Reinforced films were fabricated by impregnating paper in ethyl cellulose solutions. After solvent evaporation, the infused ethyl cellulose acted as binder of the paper microfibres and occupied the pores and cavities, thus improving the mechanical and barrier properties. To prepare active films, avocado by-products from guacamole industrial production were extracted in ethyl acetate. Then, the extract (optimized to be rich in phenolic compounds and flavonoids and mainly composed by lipids) was incorporated to the paper reinforced with the highest content of ethyl cellulose. In general, the addition of the avocado by-products extract decreased the water uptake and permeability, improved the wettability, and increased the biodegradability in seawater and the antioxidant capacity. In addition, these films acted as barriers and retainers for Escherichia coli and Bacillus cereus. The potentiality of these materials for food packaging was demonstrated by low overall migrations and a similar food preservation to common low-density polyethylene.

Recent Advances in Functional Cellulose-based Films with Antimicrobial and Antioxidant Properties for Food Packaging

The packaging of food plays a crucial role in food preservation worldwide. However, traditional packaging systems are passive layers with weak efficiency in protecting the food quality. Therefore, packaged foods are gradually spoiled due to the oxidation and growth of microorganisms. Additionally, most of the commercial packaging films are made of petroleum-based materials which raise environmental concerns. Accordingly, the development of eco-friendly natural-derived active packaging systems has increased the attention of scientists. Cellulose as the most abundant polysaccharide on earth with high biocompatibility, no toxicity, and high biodegradability has extensively been applied for the fabrication of packaging films. However, neat cellulose-based films lack antioxidant and antimicrobial activities. Therefore, neat cellulose-based films are passive films with weak food preservation performance. Active films have been developed by incorporating antioxidants and antimicrobial agents into the films. In this review, we have explored the latest research on the fabrication of antimicrobial/antioxidant cellulose-based active packaging films by incorporating natural extracts, natural polyphenols, nanoparticles, and microparticles into the cellulose-based film formulations. We categorized these types of packaging films into two main groups: (i) blend films which are obtained by mixing solutions of cellulose with other soluble antimicrobial/antioxidant agents such as natural extracts and polyphenols; and (ii) composite films which are fabricated by dispersing antimicrobial/antioxidant nano- or microfillers into the cellulose solution. The effect of these additives on the antioxidant and antimicrobial properties of the films has been explained. Additionally, the changes in the other properties of the films such as hydrophilicity, water evaporation rate, and mechanical properties have also been briefly addressed.

Biocompatible green technology principles for the fabrication of food packaging material with noteworthy mechanical and antimicrobial properties A sustainable developmental goal towards the effective, safe food preservation strategy

Biocompatible, eco-friendly, highly economical packaging methods should be needed as conventional packaging is known to cause undesirable effects. As food packaging is the major determining factor of food safety, the selection or methods of packaging materials plays a pioneering role. With this scope, modern food technology seeks unique sustainable approaches for the fabrication of package materials with notable desired properties. The principles, features, and fabrication methodology of modern food packaging are briefly covered in this review. We extensively revealed improved packaging (nanocoating, nanolaminates, and nano clay), active packaging (antimicrobial, oxygen scavenging, and UV barrier packaging), and intelligent/smart packaging (O2 indicator, CO2 indicator, Time Temperature Indicator, freshness indicator, and pH indicator). In particular, we described the role of nanomaterials in the fabrication of packaging material. Methods for the evaluation of mechanical, barrier properties, and anti-microbial assays have been featured. The present studies suggest the possible utilization of materials in the fabrication of food packaging for the production, utilization, and distribution of safe foods without affecting nutritional values.

Recent progress of bioplastics in their properties, standards, certifications and regulations: A review

The environmental impact associated with fossil fuel-based polymers has paved the way to explore biopolymer-based plastics, their properties, and their applications. Bioplastics are polymeric materials that are greatly interesting due to their eco-friendlier and non-toxic nature. In recent years, exploring the different sources of bioplastics and their applications has become one of the active research areas. Biopolymer-based plastics have applications in food packaging, pharmaceuticals, electronics, agricultural, automotive and cosmetic sectors. Bioplastics are considered safe, but there are several economic and legal challenges to implementing them. Hence, this review aims to i) outline the terminology associated with bioplastics, its global market, major sources, types and properties of bioplastics, ii) discuss the major bioplastic waste management and recovery options, iii) provide the major standards and certifications regarding bioplastics, iv) explore the various country-wise regulations and restrictions associated with bioplastics, and v) enumerate the various challenges and limitations associated with bioplastics and future directions. Therefore, providing adequate knowledge about various bioplastics, their properties and regulatory aspects can be of great importance in the industrialization, commercialization and globalization of bioplastics to replace petroleum-based products.

Acylated pectin/gelatin-based films incorporated with alkylated starch crystals: Characterization, antioxidant and antibacterial activities, and coating preservation effects on golden pomfret

Pectin and starch crystals were modified by ethyl gallate and octadecyl-trimethoxysilane, respectively, followed by using acylated pectin (AP) and alkylated starch crystals (ASCs) as bioactive reagents and hydrophobic enhancers to improve the physiochemical properties of gelatin-based films and evaluate their coating preservation effects on golden pomfret. The properties of AP and ASC were investigated by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), proton-nuclear magnetic resonance (¹H NMR) and X-ray diffraction (XRD). The ethyl-gallate-modified pectin/gelatin (AP/G) containing 3 % ASC (AP/G/ASC-3 %) was shown to have the maximum tensile strength and Young's modulus of all the tested composite films. The AP/G containing 10 % ASC exhibited a water contact angle higher than 94°, coupled with a significant improvement in UV-shielding efficiency. FTIR and SEM analysis of the AP/G/ASC-3 % film indicated that the molecular interactions in the composite film components were noncovalent linkages, including hydrogen bonds, hydrophobic interactions, and electrostatic interactions, contributing to homogeneous and smooth microstructures. Additionally, the solutions of AP/G and AP/G/ASC composite films presented obvious antioxidant and antibacterial activities against Escherichia coli and Staphylococcus aureus. Furthermore, the AP/G and AP/G/ASC active coatings could effectively inhibit lipid oxidation and improve the textural acceptability of golden pomfret (Trachinotus blochii) fillets during 4 °C storage.

Hydrophobic, Sustainable, High-Barrier Regenerated Cellulose Film via a Simple One-Step Silylation Reaction

With the increasing importance of environmental protection, high-performance biopolymer films have received considerable attention as effective alternatives to petroleum-based polymer films. In this study, we developed hydrophobic regenerated cellulose (RC) films with good barrier properties through a simple gas-solid reaction via the chemical vapor deposition of alkyltrichlorosilane. RC films were employed to construct a biodegradable, free-standing substrate matrix, and methyltrichlorosilane (MTS) was used as a hydrophobic coating material to control the wettability and improve the barrier properties of the final films. MTS readily coupled with hydroxyl groups on the RC surface through a condensation reaction. We demonstrated that the MTS-modified RC (MTS/RC) films were optically transparent, mechanically strong, and hydrophobic. In particular, the obtained MTS/RC films exhibited a low oxygen transmission rate of 3 cm³/m² per day and a low water vapor transmission rate of 41 g/m² per day, which are superior to those of other hydrophobic biopolymer films.

Cellulose/Grape-Seed-Extract Composite Films with High Transparency and Ultraviolet Shielding Performance Fabricated from Old Cotton Textiles

Plastics displaying many merits have been indispensable in daily life and they still maintain the strong momentum of development. Nevertheless, petroleum-based plastics possess a stable polymer structure and most of them are incinerated or accumulated in the environment, leading to devastating impacts on our ecology system. Thus, exploiting renewable and biodegradable materials to substitute or replace these traditional petroleum-derived plastics is an urgent and important task. In this work, renewable and biodegradable all-biomass cellulose/grape-seed-extract (GSEs) composite films with high transparency and anti-ultraviolet performance were fabricated successfully from pretreated old cotton textiles (P-OCTs) using a relatively simple, green, yet cost-effective, approach. It is proved that the obtained cellulose/GSEs composite films exhibit good ultraviolet shielding performance without sacrificing their transparency, and their UV-A and UV-B blocking values can reach as high as nearly 100%, indicating the good UV-blocking performance of GSEs. Meanwhile, the cellulose/GSEs film show higher thermal stability and water vapor transmission rate (WVTR) than most common plastics. Moreover, the mechanical property of the cellulose/GSEs film can be adjusted by the addition of a plasticizer. Briefly, the transparent all-biomass cellulose/grape-seed-extracts composite films with high anti-ultraviolet capacity were manufactured successfully and they can be used as potential materials in the packaging field.

Sustainable and Bio-Based Food Packaging: A Review on Past and Current Design Innovations

Food loss and waste occur for many reasons, from crop processing to household leftovers. Even though some waste generation is unavoidable, a considerable amount is due to supply chain inefficiencies and damage during transport and handling. Packaging design and materials innovations represent real opportunities to reduce food waste within the supply chain. Besides, changes in people's lifestyles have increased the demand for high-quality, fresh, minimally processed, and ready-to-eat food products with extended shelf-life, that need to meet strict and constantly renewed food safety regulations. In this regard, accurate monitoring of food quality and spoilage is necessary to diminish both health hazards and food waste. Thus, this work provides an overview of the most recent advances in the investigation and development of food packaging materials and design with the aim to improve food chain sustainability. Enhanced barrier and surface properties as well as active materials for food conservation are reviewed. Likewise, the function, importance, current availability, and future trends of intelligent and smart packaging systems are presented, especially considering biobased sensor development by 3D printing technology. In addition, driving factors affecting fully biobased packaging design and materials development and production are discussed, considering byproducts and waste minimization and revalorization, recyclability, biodegradability, and other possible ends-of-life and their impact on product/package system sustainability.

Poly(lactic acid) based Pearl Layer Moistureproof Membrane for Flexible Laminated Packaging

The development of bio-based polymer materials, such as polylactic acid (PLA) -based polymers, is an effective strategy to reduce dependence on petrochemical-based polymers. However, the preparation of bio-based polymers with high barrier properties is a major challenge. To overcome this challenge, a nacreous layer structure with a ' brick and mud ' pattern is mimicked to improve the overall performance of the material. In this paper, Poly (_L -lactic acid) (PLLA) and Polypropylene Glycol (PPG) was combined to prepare bio-based polyurethane (PU-PLLA), which is used as the slurry structure of nacreous layer. The bio-based biomimetic composite membrane (PU-PLLA/BN) is then obtained by adding boron nitride (BN, brick structure of pearl layer) to it. The water vapor permeability test results show that the permeability of PU-PLLA material can be reduced by more than 50% by 5 wt.% BN, which is because the addition of BN can increase the length and tortuosity of the gas molecular diffusion path in the composite. Therefore, this pearl-inspired PU-PLLA/BN film has excellent moisture resistance, which opens up a broad road for the practical application of PLLA in flexible laminated packaging.

Development and characterization of natural sourced bioplastic for food packaging applications

Climate change and increased pollution caused by traditional petrochemical plastics made the biodegradable environment-friendly plastic (bioplastic) research more popular. Bioplastics can be manufactured from natural renewable ingredients and used as food packaging material without harming the environment. This research work focuses on developing bioplastic films from natural ingredients such as starch of tamarind seeds, and berry seeds, with licorice root. Attention has been paid to characterizing the material by biodegradability, mechanical testing, Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), antimicrobial analysis tests. Phenolic compounds present in the berry seeds starch increased the soil biodegradability as well as the mechanical and thermal properties of the bioplastic films. The FTIR spectra confirmed the presence of various bio-molecules. Improved antimicrobial performance is also obtained. The results of this research confirm that the prepared bioplastic samples can be used in packaging applications.

Mechanically strong and biodegradable holocellulose films prepared from Camellia oleifera shells

Bioplastic derived from renewable lignocellulosic biomass is an attractive alternative to petroleum-based plastics. Herein, Callmellia oleifera shells (COS), a unique byproduct from tea oil industry, were delignified and converted into high-performance bio-based films via a green citric acid treatment (15 %, 100 °C and 24 h), taking advantage of their high hemicellulose content. The structure-property relations of COS holocellulose (COSH) films were systematically analyzed considering different treatment conditions. The surface reactivity of COSH was improved via a partial hydrolysis route and strong hydrogen bonding formed between the holocellulose micro/nanofibrils. COSH films exhibited high mechanical strength, high optical transmittance, improved thermal stability, and biodegradability. A mechanical blending pretreatment of COSH, which disintegrated the COSH fibers before the citric acid reaction, further enhanced the tensile strength and Young's modulus of the films up to 123.48 and 5265.41 MPa, respectively. The films decomposed completely in soil, demonstrating an excellent balance between degradability and durability.

Facile Preparation of Cellulose Bioplastic from Cladophora sp. Algae via Hydrogel Method

Bioplastic has been widely studied in the past decades as a replacement for non-biodegradable and non-environmentally friendly plastic. One of the promising materials to produce bioplastic is cellulose. However, it is rarely used as the main component for bioplastic production. This study reports a facile process to prepare bioplastic using the pure cellulose content of Cladophora sp. algae via the hydrogel method. The effect of epichlorohydrin (ECH) concentrations as the cross-linking agent was investigated toward the biodegradability, thermal, and mechanical properties of the cellulose bioplastic obtained. The results showed that ECH concentrations affected the properties of the cellulose bioplastic produced due to the number of cross-links formed during the process. The cellulose bioplastic possessed relatively high thermal and mechanical properties. The cellulose bioplastic performed excellent biodegradability, as it was degraded by more than 40% within five days. Thus, the cellulose of Cladophora sp. algae has the potential to be developed as the main component for bioplastic application.

Preparation and Characterization of Degradable Cellulose−Based Paper with Superhydrophobic, Antibacterial, and Barrier Properties for Food Packaging

A great paradigm for foremost food packaging is to use renewable and biodegradable lignocellulose−based materials instead of plastic. Novel packages were successfully prepared from the cellulose paper by coating a mixture of polylactic acid (PLA) with cinnamaldehyde (CIN) as a barrier screen and nano silica−modified stearic acid (SA/SiO2) as a superhydrophobic layer. As comprehensively investigated by various tests, results showed that the as−prepared packages possessed excellent thermal stability attributed to inorganic SiO2 incorporation. The excellent film−forming characteristics of PLA improved the tensile strength of the manufactured papers (104.3 MPa) as compared to the original cellulose papers (70.50 MPa), enhanced by 47.94%. Benefiting from the rough nanostructure which was surface−modified by low surface energy SA, the contact angle of the composite papers attained 156.3°, owning superhydrophobic performance for various liquids. Moreover, the composite papers showed excellent gas, moisture, and oil bacteria barrier property as a result of the reinforcement by the functional coatings. The Cobb300s and WVP of the composite papers were reduced by 100% and 88.56%, respectively, and their antibacterial efficiency was about 100%. As the novel composite papers have remarkable thermal stability, tensile strength, and barrier property, they can be exploited as a potential candidate for eco−friendly, renewable, and biodegradable cellulose paper−based composites for the substitute of petroleum−derived packages.