Zein electrospun nanofibers have poor water resistance, which restricts its applications in food preservation. To improve the water resistance of nanofibers, zein/ethyl cellulose (EC) hybrid nanofibers were prepared at different ratios. Besides, we also encapsulated cinnamon essential oil (CEO) into electrospun fibers for Agaricus bisporus preservation. As the weight ratio of EC increased from 0% (ZE-10) to 100% (ZE-01), the viscosity of electrospinning solutions gradually increased from 80.33 ± 19.23 mPa·s to 756.78 ± 22.48 mPa·s, resulting in sufficient chain entanglement for the preparation of uniform fibers. The average diameters of ZE-01, ZE-12, ZE-11, ZE-21, and ZE-10 nanofibers were 326 ± 53 nm, 267 ± 31 nm, 237 ± 51 nm, 292 ± 45 nm, and 362 ± 70 nm, respectively. The hydrogen bonds between the hydroxyl groups of ethyl cellulose and the amino groups of zein decreased the amount of free hydrophilic group, thus improving water resistance of nanofibers. Food packaging potential was evaluated using Agaricus bisporus. The zein/EC nanofibers loaded CEO significantly decreased weight loss and maintained the firmness of the Agaricus bisporus, and improved the quality of the Agaricus bisporus during storage.

Salmonella can survive for extended periods of time in low-moisture environments posing a challenge for modern food production. This dangerous pathogen must be controlled throughout the production chain with a minimal risk of dissemination. Limited information is currently available describing the behavior and characteristics of this important zoonotic foodborne bacterium in low-moisture food production environments and in food. In our study, the phenotypes related to low-moisture survival of 46 Salmonella isolates were examined. Most of the isolates in the collection could form biofilms under defined laboratory conditions, with 57% being positive for curli fimbriae production and 75% of the collection positive for cellulose production, which are both linked with stronger biofilm formation. Biocides in the factory environment to manage hygiene were found to be most effective against planktonic cells but less so when the same bacteria were surface dried or present as a biofilm. Cellulose-producing isolates were better survivors when exposed to a biocide compared with cellulose-negative isolates. Examination of Salmonella growth of these 18 serotypes in NaCl, KCl, and glycerol found that glycerol was the least inhibitory of these three humectants. We identified a significant correlation between the ability to survive in glycerol and the ability to survive in KCl and biofilm formation, which may be important for food safety and the protection of public health.

Natural biopolymers have become key players in the preparation of biodegradable food packaging. However, biopolymers are typically highly hydrophilic, which imposes limitations in terms of barrier properties that are associated with water interactions. Here, we enhance the barrier properties of biobased packaging using multilayer designs, in which each layer displays a complementary barrier function. Oxygen, water vapor, and UV barriers were achieved using a stepwise assembly of cellulose nanofibers, biobased wax, and lignin particles supported by chitin nanofibers. We first engineered several designs containing CNFs and carnauba wax. Among them, we obtained low water vapor permeabilities in an assembly containing three layers, i.e., CNF/wax/CNF, in which wax was present as a continuous layer. We then incorporated a layer of lignin nanoparticles nucleated on chitin nanofibrils (LPChNF) to introduce a complete barrier against UV light, while maintaining film translucency. Our multilayer design which comprised CNF/wax/LPChNF enabled high oxygen (OTR of 3 ± 1 cm³/m²·day) and water vapor (WVTR of 6 ± 1 g/m²·day) barriers at 50% relative humidity. It was also effective against oil penetration. Oxygen permeability was controlled by the presence of tight networks of cellulose and chitin nanofibers, while water vapor diffusion through the assembly was regulated by the continuous wax layer. Lastly, we showcased our fully renewable packaging material for preservation of the texture of a commercial cracker (dry food). Our material showed functionality similar to that of the original packaging, which was composed of synthetic polymers.

Although polyvinyl alcohol (PVA) is a promising biodegradable packaging material, it presents some disadvantages for food packaging such as poor ultraviolet (UV) and water vapor barrier properties, low mechanical strength, poor water resistance, and lack of antimicrobial properties. To overcome these limitations, novel PVA/cellulose nanocrystals (CNC)/titanium dioxide (TiO₂) nanocomposites were developed, characterized, and demonstrated for potential food packaging applications. The mechanical strength, water vapor barrier, and UV barrier properties of PVA/CNC/TiO₂ 5 % film (5 wt% TiO₂ in the PVA/CNC matrix with 5 wt% of CNCs) increased by 55.8 %, 45.2 %, and 70,056.8 %, respectively, compared to those of a PVA film. In the antibacterial simulation test, PVA/CNC/TiO₂ 5 % film could limit the growth of microorganisms for 14 days. In packaging tests with fresh garlic, PVA/CNC/TiO₂ films effectively prevented weight loss and spoilage by external influences, indicating the potential of the PVA/CNC/TiO₂ nanocomposites for food-packaging applications.

Paper based packaging has the potential to replace many plastic-based systems if the required barrier properties can be obtained. Water borne barrier coatings have the potential to generate good barrier layers, but their performance is often less than expected. Recent work has shown improved performance of these coatings when applied on paper that has a cellulose nanofiber layer. Here, papers with a cellulose nanofiber layer were coated with barrier coatings at different coat weights applied as single-layers, as double-layers, and single-layers pressed together in a hot press in order to generate a packaging system that has good barrier properties. The performance of double-layer samples resulted in moisture transmission rates that were 40–70 % of the value of the single-layer systems. Surprisingly, the hot-pressing of two dry layers showed no advantage compared to the single-layer system. A barrier pigment added to one formulation improved the performance further and followed the same trends. Three dimensional models of diffusion through layers that have defects help explain the results. The work shows a potential path to produce paper-based packaging that has both good oxygen and water vapor barrier properties.

Hydrophobic materials extracted from citrus wastes, both peel of mandarin fruits and leaf of mandarin trees were used to treat food-grade Kraft paper. The chemical compounds of the extracts were identified by gas chromatography–mass spectroscopy and infrared spectroscopy, and their antioxidant activities were determined using a free radical scavenger agent (2,2-diphenyl-1-picryl-hydrazyl-hydrate, DPPH). Water vapor permeability, air transmission rate, peroxide value, and microstructure of treated and original papers were also determined. The experimental results showed that: (i) most components of the peel or peel/leaf extracts were terpenes; (ii) free volume existed among cellulose macromolecule chains of the original paper, occupied by a part of extract materials, and another part of the extracts was formed a thin layer on the paper surfaces; and (iii) air and water barrier properties and antioxidant activity of the treated papers were improved, indicating that the extracts were efficient materials for food packaging applications.

We designed Air-in-Oil-in-Water (A/O/W) emulsions. First, Air-in-Oil foams were fabricated by whipping anhydrous milk fat. The maximum overrun was obtained at 20 °C. The foams contained 30–35 vol% air and were stabilized solely by fat crystals. To refine the bubble size, foams were further sheared in a Couette’s cell. The average bubble size reached a value as small as 6.5 μm at a shear rate of 5250 s−1. The nonaqueous foams were then dispersed in a viscous aqueous phase containing sodium caseinate to obtain A/O/W emulsions. The shear rate was varied from 1000 to 7500 s−1, allowing to obtain Air-in-Oil globules whose average diameter ranged from 15 to 60 μm. To avoid globule creaming, the aqueous phase was gelled by incorporating hydroxyethyl cellulose. Homogeneous emulsions were obtained with fat globules containing around 22 vol% of residual air. The systems were kinetically stable for at least 3 weeks at 4 °C.

In this study, we investigated the tailoring of food emulsions using interactions between rice bran cellulose nanocrystals (CNCs) and lauric arginate (LAE), which is food-grade cationic surfactant. Complexes of anionic CNCs and cationic LAE (CNCs/LAE) were formed through electrostatic attraction which were characterized using isothermal titration calorimetry (ITC), turbidity, and zeta-potential measurements. The saturation complexes could be formed at ratios of 1:2 (w/w) CNCs-to-LAE. Furthermore, the physical and oxidative stability of oil-in-water emulsions containing lipid droplets coated by CNCs/LAE complexes was determined. Electrostatic complexes formed from 0.02% CNCs and 0.1% LAE produced stable Pickering emulsions that were resistant to droplet coalescence. It was also exhibited that 0.02% CNCs and 0.1% LAE complexes stabilized-emulsions was able to extend the lag phase to 20 days for lipid hydroperoxide and to 14 days for hexanal production. This study shows that food-grade Pickering emulsions with good stability can be produced by CNCs with LAE complexes.

The food-energy-water (FEW) nexus is interconnected and interdependent and provides a physical foundation for mankind. The production of safe food, renewable energy, and clean water through biological means, especially microbial bioconversion, has attracted an enormous attention worldwide. Recently, in vitro synthetic enzymatic biosystems (ivSEBs) comprised of numerous enzymes and coenzymes, as a disruptive biomanufacturing platform, has been proposed and demonstrated to address key challenges at the interface of the FEW nexus. Light, electricity, and hydrogen can provide energy to fix CO2 and produce food and biomass. Lignocellulose-derived cellulose can be converted to starch and biofuels. Starch can be further converted to bioenergy, including electricity, hydrogen and liquid fuels. These high-energy efficient bioprocesses lead to significantly less water usage and also can be used to reduce water pollution. In this review, the conceptual framework and latest advances of ivSEBs in the FEW nexus are summarized. Their limitations and future research directions on the design and improvement of ivSEBs are also discussed.

Nowadays consumers are aware of environmental problems. As an alternative to petrochemical polymers for food packaging, researchers have been focused on biopolymeric materials as raw material. The aim of this study was to evaluate mechanical properties (toughness, burst strength and distance to burst), water adsorption, light-barrier properties and transparency of composite films based on cellulose, glycerol and polyvinyl alcohol. Scanning electron microscopy, spectral analysis (FT-IR and UV–VIS-NIR) and differential scanning calorimetry were performed to explain the morphology, structural and thermal properties of the films. Results showed that polyvinyl alcohol enhances the toughness of films up to 44.30 MJ/m3. However, toughness decreases when glycerol concentration is increased (from 23.41 to 10.55 MJ/m3). Water adsorption increased with increasing polyvinyl alcohol concentration up to 222%. Polyvinyl alcohol increased the film thickness. The films showed higher burst strength (up to 12014 g) than other biodegradable films. The films obtained have optimal values of transparency like those values of synthetic polymers. Glycerol produced a UV protective effect in the films, an important effect for food packaging to prevent lipid oxidative deterioration. Results showed that it is feasible to obtain cellulose-glycerol-polyvinyl alcohol composite films with improved properties.