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Biopolymeric materials have increased their uses and applications in the past years since more advanced preparations have been implemented to find the best formulation for a particular application. Holocellulose from spent coffee grounds (HOLO‐SCG) is a unique material with scarcely studied peculiarities. A detailed study of the flow behavior, microscopy, thermal, and local mechanical properties needs to be performed on biopolymeric films to open the understanding of polymer responsiveness, which is essential for the final design of the composites when fitting characteristics on macroscopic and microscopic scales are achieved. This manuscript aims to obtain biopolymer blends and films based on chitosan (CS) and polyvinyl alcohol (PVA) and reinforced with micro HOLO‐SCG. It seeks to investigate their compatibility and physicochemical properties in liquid states by rheological measurements and solid states using physicochemical, thermal, and mechanical experiments. The results indicate that the prepared CS : PVA films reinforced with HOLO‐SCG under controlled size provide an excellent biopolymeric structure with enhanced thermal and mechanical properties, which brings a stable product to be used as an alternative plastic due to their noticeable lower wettability. The biopolymeric film could be introduced as a bio‐composite material in food packaging applications in further experiments. [ABSTRACT FROM AUTHOR]

This work focuses on the potential of agar from the seaweed Gracilaria fisheri to modify the properties of starch foam. The effects of different ratios of glycerol and agar on the properties of starch foams were investigated. All formulations used in this study produced easy-to-handle, smooth, single-use foam trays with no visible cracks. The addition of agar slightly affected the off-white color of the foam but red and yellow color values significantly decreased with increments of agar content. As the agar content was increased, the foam became less dense. A foam produced at a glycerol:agar ratio of 3:7 exhibited the highest values of flexural stress at maximum load (3.23 MPa), modulus (194.46 MPa) and hardness (97.50), and the highest temperature at maximum weight loss (T max) (337 °C). Therefore, starch foam modified with agar from Gracilaria fisheri showed suitable physical, mechanical and thermal properties for food packaging, and could possibly be used in the place of expanded polystyrene (EPS) foam. [ABSTRACT FROM AUTHOR]

This work involves preparing zinc manganite nanoparticles (ZnMn 2 O 4 NPs) using the Sol-gel method. Polymer nanocomposites of polyvinyl alcohol (PVA)/Sodium alginate (NaAlg)- ZnMn 2 O 4 NPs were created using the solution casting technique. The polymer nanocomposites films were made with varying weight percentages of ZnMn 2 O 4 nanoparticles. With the addition of nanofiller, the reduced direct and indirect energy band gap values and increased Urbach energy values were discovered in the UV–Vis data. XRD data showed a reduction in crystallinity degree with dopant. ZnMn 2 O 4 NPs had a strong interaction with PVA/NaAlg blend, as confirmed by FTIR. The addition of ZnMn 2 O 4 NPs led to improved thermal stability of the polymer nanocomposites films. Additionally, the nanocomposites films' mechanical characteristics were examined. The loading of ZnMn 2 O 4 nanoparticles has been associated with an increasing trend in the mechanical properties of the nanocomposites, including its toughness, Young's modulus, Tensile strength (Ts), and elongation. The antibacterial activity of the nanocomposites against fungus and bacteria was studied. Additionally, PVA/NaAlg-ZnMn 2 O 4 nanocomposites films had good antibacterial characteristics against environmental microorganisms such as Gram-positive (G+) S. aureus and Gram-negative(G−) E. coli bacteria as well as fungi C. albicans and A. niger. It was observed that the biodegradability of the nanocomposite films was lower compared to the pure PVA/NaAlg film. Compared to pure film, the water solubility was decreased upon the addition of ZnMn 2 O 4 NPs. After ZnMn 2 O 4 was added to the pure blend, the WVTR decreased. The produced polymer nanocomposites films appear to be a promising material for food packing, according to these results. [ABSTRACT FROM AUTHOR]

Although many papers have been published in recent years regarding the effects of electrospinning (ES) on the properties of legume proteins (LPs), there has been no comprehensive review summarizing these findings, which was the main aim of this paper. Thus, the main purpose of this article was to review the properties of LP fiber-forming solutions as well as LP fibers through different characterization methods. Furthermore, the effect of encapsulating/incorporating different components into the ES solution of various LPs was studied. Cross-linking significantly improves the thermal stability, barrier properties, and insolubility of LP nanofibers. Also, Maillard-induced glycation leads to higher surface tension at the interface of oil-water contact, smaller emulsion droplets, and monomodal distributions. The ES quality of LPs varies depending on the viscosity, electrical conductivity, and surface tension of the protein solution; Specifically, too low and too high viscosity are detrimental due to the formation of beads and delay in Taylor cone formation, respectively; too low or too high conductivity will also cause insufficient jet elongation and significantly reduced jet stability, respectively. Insertion of nanoparticles improves the mechanical and thermal stability of LP nanofibers; however, the extent to which the incorporation meets safety regulations for adoption in food destinations remains a major challenge. [Display omitted] • The properties of legume protein fiber-forming solutions were reviewed. • Recent innovations in the electrospinning of legume proteins were introduced. • The role of electrospun legume proteins fibers in food packaging was explained. • The challenges in the electrospinning of legume proteins were described. [ABSTRACT FROM AUTHOR]

Carboxymethyl starch (CST) was introduced to improve gelatin films and its practical application as edible high-performance films for food packaging and cooking was also investigated. The gelatin films modified by carboxymethyl starch exhibited the transparent appearance, tensile strength, barrier properties (oxygen, water vapor and UV light), and thermal performance (TGA, thermal shrinkage and heat-sealing strength). Resulting from the effect of electrostatic interaction modes on the properties of films, electrostatic repulsion could surpass electrostatic attraction in improving the tensile strength, oxygen barrier property and thermal stability of the films probably due to extensive physical entanglement without aggregation. Analysis of FTIR, zeta potential, interfacial dilatational rheology, shear rheological properties, XRD, Raman, SEM and AFM suggested that hydrogen bonding and electrostatic repulsion contributed to the excellent performance. The packaged food could also be cooked with the prepared film for porridge; and the film slightly influenced the shear rheological properties of porridge and imposed little effect on the odors (Electronic-Nose) of porridge. Hence, the gelatin films modified by carboxymethyl starch could potentially work as the edible inner packaging or the edible quantitative packaging for food, offer convenience for consumers, reduce the packaging waste and avoid an extra burden on environment. • CST improved mechanical and barrier properties (O 2 , moisture and UV light) of films. • CST enhanced the thermal stability, thermal shrinkage and sealing strength of films. • Hydrogen bonds and electrostatic repulsion improved compact matrix and performance. • Excessive CST granules caused the weak interactions and the property deterioration. • The packaged food could cook porridge and slightly affect the rheology and odors. [ABSTRACT FROM AUTHOR]

• Poly(ethylene furanoate) (PEF) nanocomposites have been successfully synthesized. • Thermal stability and decomposition kinetics of PEF were investigated. • Thermogravimetric analysis proved that nanocomposites exhibited good thermal stability. • Degradation occurred via heterolytic β-hydrogen scission and α-homolytic scission. Poly(ethylene 2,5-furan dicarboxylate) (PEF) based nanocomposites containing different nanoparticles like Ag, TiO 2 , ZnO, ZrO 2 Ce-Bioglass, have been synthesized via in-situ polymerization techniques targeting food packaging applications. Zeta potential measurements showed an increase in the negative zeta potential value due to an increase in the surface charge density of the nanocomposites. Thermogravimetric analysis results proved that, except PEF-ZnO nanocomposite, all the other nanocomposites exhibited good resistance to thermal degradation without serious mass loss until 330 °C. Thermal decomposition kinetic analysis and the dependence of activation energy on the degree of conversion (α), indicated that the presence of ZnO nanoparticles influences, the degradation mechanism of PEF. In contrast, the presence of Ce-Bioglass nanoparticles leads to a slower degradation process, contributing to the enhanced resistance to thermal degradation of the PEF-Bioglass nanocomposite. The thermal degradation mechanism of PEF nanocomposites analyzed by pyrolysis‒gas chromatography/mass spectrometry (Py-GC/MS) indicated that the primary thermal degradation mechanism for the studied nanocomposites was β-hydrogen bond scission, while to a lesser extent, α-hydrogen bond scission products were noted in PEF-TiO 2 and PEF-ZrO 2 nanocomposites. [ABSTRACT FROM AUTHOR]

To overcome the limitations of chitosan (CS) and konjac glucomannan (KGM), the bilayer films of CS and KGM were prepared by layer-by-layer (LBL) casting method, and the effects of different mass ratios (i.e., C5: K0, C4:K1, C3:K2, C1:K1, C2:K3, C1:K4, and C0:K5) on the microstructures and physicochemical properties of bilayer films were examined to evaluate their applicability in food packaging. The results revealed that the bilayer films had uniform microstructures. When compared with pure films, the bilayer films displayed lower swelling degrees and water vapor permeability. However, the tensile tests revealed a reduction in the mechanical properties of the bilayer films, which was nonetheless superior to that of the pure KGM film. In addition, the intermolecular interactions between the CS and KGM layers were observed through FTIR and XRD analyses. Finally, TGA and DSC analyses demonstrated a decrease in the thermal stability of the bilayer films. Our cumulative results verified that CS-KGM bilayer films may be a promising material for use in food packaging and further properties of the bilayer films can be supplemented in the future through layer-by-layer modification and the addition of active ingredients. • There was good material compatibility between CS and KGM, which formed a uniform and dense bilayer structure. • Compared with pure films, the bilayer films displayed lower swelling degrees and water vapor permeability. • Complexed with CS significantly improves the mechanical properties and reduces the water solubility of pure KGM film. • The optimum mass ratio of CS and KGM in the bilayer films is suggested to be 1:1. [ABSTRACT FROM AUTHOR]