Eugenol/silk fibroin nanoparticles embedded Lycium barbarum polysaccharide nanofibers for active food packaging

From nature to nanotech: Harnessing the power of electrospun polysaccharide-based nanofibers as sustainable packaging

Today, the applications of natural polysaccharide-based nanofibers are growing in drug delivery and food industries. They also showed their capability as packaging due to biodegradability, mechanical strength, barrier properties, thermal stability, antioxidant, and antimicrobial features. Natural polysaccharides come from different sources, such as plants, microbes, and animals. Natural polysaccharide-based nanofibers can be considered sustainable packaging in contrast to plastic packaging due to their safety and biodegradability. Smart packaging is a new trend in packaging materials, and natural polysaccharides can be applied as smart packaging. They can work as an indicator that confirms food health in food packaging. Electrospinning is one of the most used methods for the fabrication of nanofibers, and it can also be used for the fabrication of natural polysaccharide nanofibers. This method can be scaled up and used to fabricate nanofibers on a large scale. This paper will review recent studies on natural polysaccharide-based nanofiber as packaging materials and their benefits. We also discuss the challenges and limitations of their scale-up and electrospinning process. Furthermore, we will discuss the future perspective of natural polysaccharide-based nanofiber as a new sustainable packaging.

Silk Fibroin Nanoparticles as a Drug Delivery System of 3,3'-Diindolylmethane with Potential Antiobesogenic Activity

Obesity is a global disease characterized by excessive lipid accumulation in the adipose tissue. There is an urgent need to explore alternative compounds to treat obesity. Low-molecular-weight compounds from plants, like 3,3'-diindolylmethane (DIM), are emerging as potential alternatives for obesity treatment. In this work, DIM is encapsulated into silk fibroin nanoparticles (SFNP) to evaluate the antiobesogenic potential. The obtained spherical-like SFNPs have a particle size between 165 and 200 nm, a polydispersity index between 0.11 and 0.15, and a zeta potential from -27 to -37 mV. DIM does not modify the nanoparticle shape but changes the secondary structure of fibroin and generates smaller nanoparticles (145 nm). DIM-loaded SFNP (SFNP-DIM) enhance their antioxidant capacity by 4.4-fold compared to SFNP. SFNP-DIM does not show cytotoxicity on white-like adipocytes, unlike 3T3-L1 preadipocytes, where cell viability decreased in a concentration-dependent manner. The SFNP-DIM treatment (5 μM, 0.03 mg SFNP mL-1) does not modify the morphology of white-like adipocytes. It produces an apparent augmentation in the size and number of intracellular lipid droplets and increases by 2.18 ± 0.4-fold of triglyceride content. These findings demonstrated that SFNPs could be a potential delivery system of DIM, suggesting a potential therapeutic agent for treating obesity.

Fabrication of guar gum/chitosan edible films reinforced with orange essential oil nanoemulsion for cheese preservation

Inner Mongolian cheese is easily spoiled during storage due to hydrolysis and microbial contamination. Herein, the guar gum (GG)/chitosan (CS) edible films reinforced with orange essential oil nanoemulsion (OEON) were fabricated for cheese preservation. Results showed 4 % OEON with the optimal droplet size (380 ± 44.07 nm) and uniform distribution exhibited commendable compatibility with the GG/CS edible films, leading to an improvement in the oxygen and water vapor barrier properties, concomitantly mitigating their hydrophilic nature, with decreasing moisture content (from 96.86 % to 34.69 %) and water solubility (from 72.27 % to 69.76 %), while an increasing water contact angle (from 59.9° to 113.8°). The addition of 4 % OEON into the GG/CS edible films yielded a slight decrease in the tensile strength, but the elongation at break significantly increased to 135.12 %, indicating the improvement of mechanical properties. Moreover, the GG/CS-OEON edible films demonstrated outstanding biodegradability, thermal stability, and antimicrobial properties. Particularly, GG/CS-OEON 3:1 edible films packaging could maintain the stability of the weight loss, pH, color, and textural changes, retard the bacterial growth and delay the lipid oxidation of the cheese samples, thereby ensuring the cheese quality and safety. Findings here demonstrated the promising potential application of GG/CS-OEON 3:1 edible films in Inner Mongolian cheese preservation.

Nano/micro flexible fiber and paper-based advanced functional packaging materials

Recently, fiber-based and functional paper food packaging has garnered significant attention for its versatility, excellent performance, and potential to provide sustainable solutions to the food packaging industry. Fiber-based food packaging is characterized by its large surface area, adjustable porosity and customizability, while functional paper-based food packaging typically exhibits good mechanical strength and barrier properties. This review summarizes the latest research progress on food packaging based on fibers and functional paper. Firstly, the raw materials used for preparing fiber and functional paper, along with their physical and chemical properties and roles in food packaging, were discussed. Subsequently, the latest advancements in the application of fiber and paper materials in food packaging were introduced. This paper also discusses future research directions and potential areas for improvement in fiber and functional paper food packaging to further enhance their effectiveness in ensuring food safety, quality, and sustainability.

Efficient Inhibition of Ice Recrystallization During Frozen Storage: Based on the Diffusional Suppression Effect of Silk Fibroin

Effectively controlling ice recrystallization (IR) during the frozen storage of food remains highly challenging. Inspired by the structural characteristics of antifreeze proteins in nature, silk fibroin (SF) derived from silk fibers has been developed. Through dual validation using the "splat" assay and "sucrose sandwich" assay, the IR inhibition activity of SF at various concentrations was confirmed, revealing that its regular alternating hydrophilic/hydrophobic domains endow SF with the potential to inhibit the axial growth of single ice crystal and significantly reduce the average maximum crystal size by approximately 67%. Additionally, the quality stability of frozen muscle foods treated with SF was comprehensively evaluated. In stark contrast to traditional commercial antifreeze agents (4% sucrose and 4% sorbitol), prepared steaks with the addition of 2% SF maintained rich juiciness and excellent color acceptability over a three-month frozen storage period. Thus, SF holds promise as a potential protective agent for frozen muscle foods, enhancing their quality during storage.

Food-packaging applications and mechanism of polysaccharides and polyphenols in multicomponent protein complex system: A review

With the increasingly mature research on protein-based multi-component systems at home and abroad, the current research on protein-based functional systems has also become a hot spot and focus in recent years. In the functional system, the types of functional factors and their interactions with other components are usually considered to be the subjective factors of the functional strength of the system. Because this process is accompanied by the transfer of protons and electrons in the system, it has antioxidant, antibacterial and anti-inflammatory properties. Polyphenols and polysaccharides have the advantages of wide source, excellent functionality and good compatibility with proteins, and have become excellent and representative functional factors. However, polyphenols and polysaccharides are usually accompanied by poor stability, poor solubility and low bioavailability when used as functional factors. Therefore, the effect of separate release and delivery will inevitably lead to non-significant or direct degradation. After forming a multi-component composite system with the protein, the functional factor will form a stable system driven by hydrogen bonds, hydrophobic forces and electrostatic forces between the functional factor and the protein. When used as a delivery system, it will protect the functional factor, and when released, through the specific recognition of the cell membrane receptor signal, the effect of fixed-point delivery is achieved. In addition, this multi-component composite system can also form a functional composite film by other means, which has a long-term significance for prolonging the shelf life of food and carrying out specific antibacterial.

Effect of soy protein isolate nanoparticles loaded with litsea cubeba essential oil on performance of lentinan edible films

Environmental issues caused by plastic packaging materials have gotten increasingly severe, and substantial research has been conducted on environmentally friendly active packaging materials. In this study, the Litsea cubeba essential oil loaded soy protein isolate nanoparticles (LSNPs) with appropriate particle size, high storage stability and salt solution stability were fabricated. The LSNPs with the highest encapsulation efficiency of 81.76 % were added into the lentinan edible film. The microstructures of the films were observed by scanning electron microscopy. The physical properties of the films were measured. The results show that the lentinan film with LSNPs in the volume ratio of 4:1 (LF-4) had the highest elongation at break of 196 %, the lowest oxygen permeability of 12 meq/kg, and good tensile strength, water vapor barrier property, antibacterial property, oxidation resistance and thermal stability. The study suggested that LF-4 film could inhibit the growth of bacteria and delay the oxidation of lipid and protein on beef surface for 7 d.

Development of fish gelatin/carrageenan/zein bio-nanocomposite active-films incorporated with turmeric essential oil and their application in chicken meat preservation

Gelatin/carrageenan (Ge/Car) active packaging films incorporated with turmeric essential oil (TEO) encapsulated in zein nanoparticles (ZNP) were developed. The efficacy of these active packaging films and their antimicrobial properties were also investigated to ensure their practical application. Three different types of nanocomposite films (Ge/Car, Ge/Car/TEO, and Ge/Car/ZNP) were prepared. The characterization of the films was elucidated using Fourier transform infrared (FTIR), X-ray diffraction analyses (XRD), and scanning electron microscope (SEM). Physicochemical and mechanical properties of the films were enhanced, owing to the application of TEO-containing nanocomposites. Supercritical-CO₂ extracted TEO showed excellent biological activities, alongside GC-MS analysis identified that TEO contained 33 bioactive compounds where the major constituent was Zingiberene. ZNP proved an excellent carrier of TEO. The nanocomposite film sustainably released TEO, improving the shelf life of the chicken meat by reducing bacterial colonies from 3.08 log CFU/g to 2.81 log CFU/g after 14 days incubation against Salmonella enterica compared with 6.66 log CFU/g observed in the control film. The overall results of this study suggest that the nanocomposite active film is an excellent candidate for food packaging to ensure a better world.

Insights into electrospun pullulan-carboxymethyl chitosan/PEO core-shell nanofibers loaded with nanogels for food antibacterial packaging

Nisin, a natural substance from Lactococcus lactis, displays a promising antibacterial ability against the gram-positive bacteria. However, it is susceptible to the external environment, i.e. temperature, pH, and food composition. In this study, a dual stabilization method, coaxial electrospinning, was applied to protect nisin in food packaging materials and the effect of nisin concentration on the properties of the nanofibers was investigated. The core-shell nanofibers with pullulan as a core layer and carboxymethyl chitosan (CMCS)/polyethylene oxide (PEO) as shell layer were prepared, and then the prepared CMCS-nisin nanogels (CNNGs) using a self-assembly method were loaded into the core layer of the nanofibers as antibacterial agents. The result revealed that the smooth surface can be observed on the nanofibers by microstructure characterization. The CNNGs-loaded nanofibers exhibited enhanced thermal stability and mechanical strength, as well as excellent antibacterial activity. Importantly, the as-formed nanofibers were applied to preserve bass fish and found that the shelf life of bass fish packed by CNNGSs with nisin at a concentration of 8 mg/mL was effectively extended from 9 days to 15 days. Taken together, the CNNGs can be well stabilized with the core-shell nanofibers, thus exerting significantly improved antimicrobial stability and bioactivity. This special structure exerts a great potential for application as food packaging materials to preserve aquatic products.

Superhydrophobic and highly moisture-resistant PVA@EC composite membrane for air purification

Electrospun fiber membranes have great potential in the field of air filtration because of their high porosity and small pore size. Conventional air filtration membranes are hydrophilic, leading to weak moisture-barrier properties, which hinders their application in high-humidity environments. In this study, eugenol was added to polyvinyl alcohol and ethyl cellulose (EC) for electrospinning and electrospraying, respectively, of superhydrophobic bilayer composite fiber membranes to efficiently filter particulate matter (PM) in air. Owing to its surface microstructure, electrosprayed EC increased the water contact angle of the PVA membrane from 142.8 to 151.1°. More importantly, the composite air-filter membrane showed a low filtration pressure drop (168.1 Pa) and exhibited high filtration efficiencies of 99.74 and 99.77% for PM1.0 and PM2.5, respectively, and their respective quality factors were 0.0351 and 0.0358 Pa-1. At the same time, the filtration performance of the air filtration membrane remained above 99% at high air humidity. This work reports composite membranes that can effectively capture PM of various sizes and thus may provide a reference for the manufacturing of green air filters for high-humidity environments.