Recent advances in plant protein-based sustainable edible film and coatings for applications in the food-pharma industry - Opportunities and challenges: A review

Plant protein-based edible film and coatings have emerged as eco-friendly alternatives to synthetic packaging, offering biodegradable, non-toxic solutions. Their biocompatibility and film-forming properties make them suitable for direct application on food products, reducing reliance on non-degradable plastics and lowering environmental pollution. Despite their promising advantages, challenges remain in optimizing mechanical properties, production scalability, and consumer acceptance. This review explores various plant protein sources, latest developments in film-forming techniques, and approaches to address current challenges in developing protein-based film and coatings, highlighting their potential applications in food-pharma industries. Plant-based protein films and coatings have good gas barriers and mechanical qualities. Using plasticizers and post treatments improved physical and mechanical properties of protein-based film and coatings. Moreover, plant protein-based films (PBFs) with active components can slow microbial growth and lipid oxidation. Overall, plant protein-based edible films and coatings hold promise for improving food quality and safety by incorporating bioactive compounds and enhancing barrier properties. However, gaps remain in optimizing their physio-mechanical characteristics, scaling up production, and exploring novel protein sources for diverse applications in food and pharmaceuticals.

Study of the synergistic properties of copaiba oil co-electrospun with poly(L-co-D,L lactic acid) and natural rubber latex for application in bioactive wound dressings

Wound healing is a complex process involving a sequence of factors that can be disrupted, negatively impacting the quality of life for patients and overburdening healthcare systems. Advanced dressings obtained by electrospinning are highlighted by the optimization of this process, allowing air exchange and protection against microorganisms. Aiming to develop bioactive dressings, this study investigated the physicochemical, mechanical, microbiological, and in vitro biological properties of membranes containing 25 %, 50 %, 75 %, and 90 % copaiba oil (CO) co-electrospun with poly(L-co-D,L-lactic acid) (PLDLA) and natural rubber latex (NR). CO, with antimicrobial and anti-inflammatory properties, was co-electrospun with the system, which integrates the bioactivity and elasticity of NR with the mechanical strength of PLDLA. FTIR analysis indicated a physical interaction between CO and PLDLA/NR, promoting its efficient and sustained release. Scanning electron microscopy (SEM) revealed a fibrous and porous morphological structure. The mechanical tensile test revealed the plasticizing effect of CO. The low Young's modulus (26.6 MPa) for 25 % CO indicated its elastic capacity under low stress. In vitro tests have demonstrated efficacy in preventing bacterial infections against Staphylococcus aureus, due to its bacteriostatic effect and air-filtering capacity, allowing gas exchange while preventing the entry of microorganisms. The system composed of PLDLA/NR/25 % CO also exhibited cell viability of 93 % and 80 % after 24 and 72 h, respectively. The scratch assay using PLDLA/NR/25 % CO demonstrated efficacy in promoting cell migration. These results suggest that co-electrospun membranes hold promise as advanced wound dressings, with the potential to accelerate the wound healing process.

Bacterial nanocellulose-based nanopaper activated by β-cyclodextrin/ Salvia officinalis essential oil complexes for shelf life extension of shrimp

Active bacterial nanocellulose (BNC) nanopapers containing Salvia officinalis essential oil (SEO) in free form and encapsulated with β-cyclodextrin (βCD) were prepared, and their effect on the shelf life extension of shrimp was investigated. The GC-MS analysis of the SEO indicated the presence of various active compounds such as Thujone (21.53 %), Ledol (12.51 %) and Eucalyptol (11.28 %) in the essential oil composition. The cytotoxicity of the SEO and SEO-βCD complexes in the L929 cell line was quite low. FTIR analysis revealed new interactions in the nanopapers containing SEO-βCD complexes. Microscopic images showed that SEO-βCD complexation improved the surface morphology of the BNC nanopapers, whereas free SEO had a negative effect. X-ray diffraction patterns of the nanopapers showed higher crystallinity of the SEO-βCD containing nanopapers than that of the SEO-incorporated nanopapers. Moreover, the addition of the SEO-βCD complex improved the thermal properties of the BNC nanopaper. Water contact angle analysis showed higher hydrophobicity of the samples containing free SEO than that of the other samples. Both SEO-βCD and free SEO increased the elongation at break and decreased the tensile strength of the nanopaper. The prepared active films showed a greater antimicrobial effect on L. monocytogenes than on E. coli. The results showed a higher antioxidant capacity of the free SEO-containing nanopapers (58-78 %). The desirable effects of the active nanopapers on shrimp preservation were demonstrated by the results obtained for the microbial load, pH, and volatile nitrogen content of the product. The results demonstrate the potential of the prepared BNC active nanopapers for use in active antioxidant/antimicrobial food packaging.

Protein-Based Packaging Films in Food: Developments, Applications, and Challenges

With the emphasis placed by society on environmental resources, current petroleum-based packaging in the food industry can no longer meet people's needs. However, new active packaging technologies have emerged, such as proteins, polysaccharides, and lipids, in which proteins are widely used for their outstanding gel film-forming properties. Most of the current literature focuses on research applications of single protein-based films. In this paper, we review the novel protein-based packaging technologies that have been used in recent years to categorize different proteins, including plant proteins (soybean protein isolate, zein, gluten protein) and animal proteins (whey protein isolate, casein, collagen, gelatin). The advances that have recently been made in protein-based active packaging technology can be understood by describing protein sources, gel properties, molding principles, and applied research. This paper presents the current problems and prospects of active packaging technology, provides new ideas for the development of new types of packaging and the expansion of gel applications in the future, and promotes the development and innovation of environmentally friendly food packaging.

Beyond brewing: β-acid rich hop extract in the development of a multifunctional polylactic acid-based food packaging

Hops' (Humulus lupulus L.) phytochemicals are well known for their bioactivity. In the present study, the functional properties of hop extract rich in β-acids, as potassium-salts structures (KBA), were investigated to develop a sustainable active food packaging. Polylactic acid (PLA)-based sheets were incorporated with increasing concentrations of hop extract (0.1-5 % w/w in terms of KBA) and characterized through performance and bioactive properties. KBA-added sheets presented decreased crystallinity and affected mechanical and thermal properties, especially with higher KBA amounts. The sheets' surface hydrophobicity gradually decreased by KBA-extract addition, while the water vapor permeability was not affected. A Fickian diffuse behavior and a better fit to application in fatty foods were observed during release tests. UV-blocking and antioxidant properties were improved by KBA incorporation. Furthermore, results from antibacterial assays revealed great susceptibility of Staphylococcus aureus and Listeria monocytogenes towards sheets added with 5 % of KBA. Moreover, the atomic force microscopy (AFM) observations revealed that KBA led to strong effects on the cell membranes of both bacteria, including disruption of membrane integrity and cell death. Therefore, this study is a sign of great prospects of hop β-acids use, as KBA compound, in the production of sustainable active packaging for safe food shelf-life extension.