Preparation and Characterization of Chinese Leek Extract Incorporated Cellulose Composite Films

This study aimed to prepare microcrystalline cellulose (MCC) films with good mechanical properties via plasticization using a Chinese leek (CL, Allium tuberosum) extract. The microstructure, crystal structure, mechanical properties, barrier ability, and thermal properties of the films were investigated. The chemical structure analysis of CL extract showed the existence of cellulose, lignin, and low-molecular-weight substances, such as polysaccharides, pectins, and waxes, which could act as plasticizers to enhance the properties of MCC:CL biocomposite films. The results of scanning electron microscopy and atomic force microscopy analyses indicated the good compatibility between MCC and CL extract. When the volume ratio of MCC:CL was 7:3, the MCC:CL biocomposite film exhibited the best comprehensive performance in terms of water vapor permeability (2.11 × 10–10 g/m·s·Pa), elongation at break (13.2 ± 1.8%), and tensile strength (24.7 ± 2.5 MPa). The results of a UV absorption analysis demonstrated that the addition of CL extract improved the UV-shielding performance of the films. Therefore, this work not only proposes a facile method to prepare MCC films with excellent mechanical properties via plasticization using CL extract but also broadens the potential applications of MCC films in the packaging area.

Development of Multifunctional Pullulan/Chitosan-Based Composite Films Reinforced with ZnO Nanoparticles and Propolis for Meat Packaging Applications

Pullulan/chitosan-based multifunctional edible composite films were fabricated by reinforcing mushroom-mediated zinc oxide nanoparticles (ZnONPs) and propolis. The ZnONPs were synthesized using enoki mushroom extract and characterized using physicochemical methods. The mushroom-mediated ZnONPs showed an irregular shape with an average size of 26.7 ± 8.9 nm. The combined incorporation of ZnONPs and propolis pointedly improved the composite film’s UV-blocking property without losing transparency. The reinforcement with ZnONPs and propolis improved the mechanical strength of the pullulan/chitosan-based film by ~25%. Additionally, the water vapor barrier property and hydrophobicity of the film were slightly increased. In addition, the pullulan/chitosan-based biocomposite film exhibited good antioxidant activity due to the propolis and excellent antibacterial activity against foodborne pathogens due to the ZnONPs. The developed edible pullulan/chitosan-based film was used for pork belly packaging, and the peroxide value and total number of aerobic microorganisms were significantly reduced in meat wrapped with the pullulan/chitosan/ZnONPs/propolis film.

Characterization of Polyvinyl Alcohol (PVA) as Antimicrobial Biocomposite Film: A Review

Packaging is a critical process in the food industry because it is used to prevent spoilage, extend shelf-life, and provide an attractive presentation of the food product. Plastic packaging is used all over the world, and its production is increasing year after year. It comes in a variety of colours and designs. However, it has caused serious environmental problems, particularly to the ocean that has become a place for discarded plastic packaging. To address this issue, biodegradable packaging was developed to replace the use of plastic packaging because it helps to reduce environmental impact and waste management costs. Biodegradable packaging is also known as environmentally friendly packaging because it can be degraded into carbon dioxide, water, inorganic compounds, and biomass by microorganisms, algae, fungi, as well as enzyme catalysts. Biodegradable biocomposite film such as starch, cellulose, chitosan, and polyvinyl alcohol (PVA) is required to produce biodegradable packaging. Therefore, this paper aims to characterize PVA as a biocomposite film in biodegradable packaging. PVA has excellent properties to form films, as well as biodegradable, abundant in the environment, and cost-effective. However, it has some limitations in terms of thickness and mechanical properties; thus, the incorporation of PVA with essential oils and fiber is required to improve its mechanical properties, thickness, and provide antimicrobial properties to the packaging.

Electrical and Mechanical Properties of Sugarcane Bagasse Pyrolyzed Biochar Reinforced Polyvinyl Alcohol Biocomposite Films

Biochar obtained from the oxygen-deficient thermochemical processing of organic wastes is considered to be an effective reinforcing agent in biocomposite development. In the present research, biocomposite film was prepared using sugarcane bagasse pyrolyzed biochar and polyvinyl alcohol (PVA), and its electrical and mechanical properties were assessed. The biocomposite films were produced by varying content (5 wt.%, 8 wt.% and 12 wt.%) of the biochar produced at 400 °C, 600 °C, 800 °C and 1000 °C and characterized using X-Ray diffraction, scanning electron microscope, Fourier transform infrared spectroscopy. The experimental findings revealed that biochar produced at a higher pyrolyzing temperature could significantly improve the electrical conductance of the biocomposite film. A maximum electrical conductance of 7.67 × 10−2 S was observed for 12 wt.% addition of biochar produced at 1000 °C. A trend of improvement in the electrical properties of the biocomposite films suggested a threshold wt.% of the biochar needed to make a continuous conductive network across the biocomposite film. Rapid degradation of tensile strength was observed with an increasing level of biochar dosage. The lowest tensile strength 3.12 MPa was recorded for the film with 12 wt.% of biochar produced at 800 °C. Pyrolyzing temperature showed a minor impact on the mechanical strength of the biocomposite. The prepared biocomposites could be used as an electrically conductive layer in electronic devices.

Optimization and Characterization of Bioactive Biocomposite Film Based on Orange Peel Incorporated With Gum Arabic Reinforced by Cr2O3 Nanoparticles

In this paper, the effect of adding gum Arabic at levels of 0-5%, and chromium oxide nanoparticles (Cr2O3 NPs) at levels of 0-3%, are investigated on orange peel-based films. The obtained results reveal a significant increase (p<0.05) in water vapor permeability, weight loss, tensile strength, and Young's modulus of film samples by increasing the percentage of both gum and nanoparticles. Moreover, the addition of gum Arabic and Cr2O3 NPs decreases the thickness, water-solubility, L*, a*, b* indexes while increasing the elongation to the breaking point. Furthermore, the moisture content of the film samples was decreased by the addition of nanoparticles, however, the addition of gum Arabic increased this parameter. The obtained results from the morphology of the samples indicated an increase in both roughness and cracks by increasing the percentage of nanoparticles as well as creating a smooth surface with the addition of gum Arabic. Besides, the results of FTIR revealed no new peak in the prepared samples, as compared to the control sample. The results of XRD indicated that the addition of gum Arabic and nanoparticles simultaneously caused the formation of new crystals and increasing the crystallinity of the films. Based on TGA results, the thermal stability of films containing the nanoparticles increased, as compared to the control sample. In the meantime, the addition of gum and nanoparticles increased the antimicrobial properties of the film samples, as compared to the control. Overall, those films created by the orange peel including gum Arabic and Cr2O3 NPs could enhance the mechanical properties and water vapor permeability of the samples.