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It is a formidable challenge in thermoplastic/lignin composites to simultaneously boost tensile strength and elongation performance due to the rigidity of lignin. To address this issue, sodium-alginate-doped lignin nanoparticles (SLNPs) were prepared by combining solvent exchange and a coprecipitation method and used as an eco-friendly filler for poly(butylene adipate-co-terephthalate) (PBAT). The results indicated that the 1% polyanionic sodium alginate solution contributed to the formation of SLNP in lignin/THF solution. SLNP with a mean hydrodynamic diameter of ~500 nm and a Zeta potential value of −19.2 mV was obtained, indicating more hydrophobic lignin nanoparticles and a smaller number of agglomerates in SLNP suspension. Only 0.5 wt% SLNP addition improved the yield strength, tensile strength, and elongation at break by 32.4%, 31.8%, and 35.1% of the PBAT/SLNP composite films, respectively. The reinforcing effect resulted from the rigid aromatic structure of SLNP, whereas the enhanced elongation was attributed to the nanostructural feature of SLNP, which may promote boundary cracking. Additionally, the PBAT/SLNP composite films displayed excellent ultraviolet (UV) resistance with a UV shielding percentage near 100% for UVB and more than 75% for UVA, respectively. The addition of SLNP hindered water vapor, enhancing the moisture barrier properties. Overall, this study provides an effective strategy to eliminate the decrement in elongation performance for PBAT/lignin composites and suggest they are good candidates to be extensively utilized. [ABSTRACT FROM AUTHOR]

BACKGROUND: Encapsulation is commonly used to protect probiotics against harsh stresses. Thus, the fabrication of microcapsules with special structure is critical. In this work, microcapsules with the structure of S/O/W (solid-in-oil-in-water) emulsion were prepared for probiotics, with butterfat containing probiotics as the inner core and with whey protein isolate fibrils (WPIF) and antioxidants (epigallocatechin gallate, EGCG; glutathione, GSH) as the outer shell. RESULTS: Based on the high viscosity and good emulsifying ability of WPIF, dry well-dispersed microcapsules were successfully prepared via the stabilization of the butterfat emulsion during freeze-drying with 30-50 g L-1 WPIF. WPIF, WPIF + EGCG, and WPIF + GSH microcapsules with 50 g L-1 WPIF protected probiotics very well against different stresses and exhibited similar inactivation results, indicating that EGCG and GSH exerted neither harm or protection on probiotics. This significantly reduced the harmful effects of antioxidants on probiotics. Almost all the probiotics survived after pasteurization, which was critical for the use of probiotics in other foods. The inactivation values of probiotics in microcapsules were around 1 log in simulated gastric juice (SGJ), about 0.5 log in simulated intestinal juice (SIJ), and around 1 log after 40 days of ambient storage. CONCLUSION: Dry S/O/W microcapsule, with butterfat containing probiotics as the inner core and WPIF as the outer shell, significantly increased the resistance of probiotics to harsh environments. This work proposed a preparation method of dry S/O/W microcapsule with core/shell structure, which could be used in the encapsulation of probiotics and other bioactive ingredients. [ABSTRACT FROM AUTHOR]

In this study, two multi-layer fabric systems intended for firefighters have been tested in order to determine the basic parameters of thermal comfort. The thermal comfort is evaluated effectively by measuring the thermal properties of clothing on the sweating-guarded hotplate (skin model). The first assembly is composed of an external layer, a middle layer (thermal insulation), and an inner layer [moisture barrier - hydrophilic polyurethane (PU) membrane coated on knitted fabric]. The second one contains an external layer, a middle layer (thermal insulation), and an inner layer (liner). Both assemblies contain the same external layer and middle layer. These layers are tested as monolayers and in multi-layer clothing systems. The influence of the membrane on the thermal and water-vapour resistance of the multi-layer fabric system has been studied. When the combinations of different materials are used for a multi-layer fabric system, the thermal comfort is dependent not only on the properties of each monolayer but also on the manner in which they act together. The results show that the monolayer acting as a moisture barrier has a considerable influence on the overall watervapour transport abilities. The position of the moisture barrier in the assembly is also important in the overall value of watervapour resistance of the multi-layer system. [ABSTRACT FROM AUTHOR]

It is a formidable challenge in thermoplastic/lignin composites to simultaneously boost tensile strength and elongation performance due to the rigidity of lignin. To address this issue, sodium-alginate-doped lignin nanoparticles (SLNPs) were prepared by combining solvent exchange and a coprecipitation method and used as an eco-friendly filler for poly(butylene adipate-co-terephthalate) (PBAT). The results indicated that the 1% polyanionic sodium alginate solution contributed to the formation of SLNP in lignin/THF solution. SLNP with a mean hydrodynamic diameter of ~500 nm and a Zeta potential value of −19.2 mV was obtained, indicating more hydrophobic lignin nanoparticles and a smaller number of agglomerates in SLNP suspension. Only 0.5 wt% SLNP addition improved the yield strength, tensile strength, and elongation at break by 32.4%, 31.8%, and 35.1% of the PBAT/SLNP composite films, respectively. The reinforcing effect resulted from the rigid aromatic structure of SLNP, whereas the enhanced elongation was attributed to the nanostructural feature of SLNP, which may promote boundary cracking. Additionally, the PBAT/SLNP composite films displayed excellent ultraviolet (UV) resistance with a UV shielding percentage near 100% for UVB and more than 75% for UVA, respectively. The addition of SLNP hindered water vapor, enhancing the moisture barrier properties. Overall, this study provides an effective strategy to eliminate the decrement in elongation performance for PBAT/lignin composites and suggest they are good candidates to be extensively utilized.

Barrier materials are crucial in preserving product quality, safety and longevity across numerous applications, thereby contributing to sustainability, reducing waste and advancing technology. Among these materials, cellulose nanomaterials (CNs) have emerged as promising alternatives for traditional petroleum-based polymers. However, the wide range of sources and the different methods used to isolate and process CN-based materials can result in significant variations in moisture and oxygen barrier performance. In this review, we provide an in-depth discussion on the latest advancements in CN-based green barrier materials. We begin by offering a critical assessment of the barrier performance of CNs, both in their isolated form and when combined as hybrid materials. This includes their applications as standalone films, fillers and coatings in nanocomposites. This review also covers the influence of the isolation process and the stages of film formation on barrier efficacy. We further discuss the implications of the recycling process on barrier properties of CN-based materials, drawing a connection between barrier characteristics and the product's end-of-life. We conclude by highlighting the significant developments over the past five years, the present challenges, and the prospective future of CN-based materials in barrier applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Nowadays, resource efficiency is critical for sustainability. This study investigates the use of high moisture barrier plastic casing as an alternative to traditional cellulose casing in sausage production, based on various innovative initiatives for sausage production by many casing suppliers. The plastic casing significantly reduces water loss during processing, leading to positive environmental and economic impacts. Various parameters including texture, shelf life, color analysis, and casing durability were examined. Results show no significant differences in chemical composition between products with plastic casing and those with traditional casing. However, texture analysis revealed differences, particularly in adhesiveness and springiness. Significant color variations were also observed. The study anticipates substantial water savings and energy conservation through the use of plastic casing, with a projected reduction in water consumption of 3,680 tons per month and energy savings of 1.36 kWh/ton through oven program optimization. This study demonstrates that the high moisture barrier polyamide casing can be used as an alternative. [ABSTRACT FROM AUTHOR]

Background: Encapsulation is commonly used to protect probiotics against harsh stresses. Thus, the fabrication of microcapsules with special structure is critical. In this work, microcapsules with the structure of S/O/W (solid-in-oil-in-water) emulsion were prepared for probiotics, with butterfat containing probiotics as the inner core and with whey protein isolate fibrils (WPIF) and antioxidants (epigallocatechin gallate, EGCG; glutathione, GSH) as the outer shell., Results: Based on the high viscosity and good emulsifying ability of WPIF, dry well-dispersed microcapsules were successfully prepared via the stabilization of the butterfat emulsion during freeze-drying with 30-50 g L -1 WPIF. WPIF, WPIF + EGCG, and WPIF + GSH microcapsules with 50 g L -1 WPIF protected probiotics very well against different stresses and exhibited similar inactivation results, indicating that EGCG and GSH exerted neither harm or protection on probiotics. This significantly reduced the harmful effects of antioxidants on probiotics. Almost all the probiotics survived after pasteurization, which was critical for the use of probiotics in other foods. The inactivation values of probiotics in microcapsules were around 1 log in simulated gastric juice (SGJ), about 0.5 log in simulated intestinal juice (SIJ), and around 1 log after 40 days of ambient storage., Conclusion: Dry S/O/W microcapsule, with butterfat containing probiotics as the inner core and WPIF as the outer shell, significantly increased the resistance of probiotics to harsh environments. This work proposed a preparation method of dry S/O/W microcapsule with core/shell structure, which could be used in the encapsulation of probiotics and other bioactive ingredients., (© 2023 Society of Chemical Industry.)