Water Vapor Permeability Research Articles

Sodium alginate edible films incorporating cactus pear extract: antimicrobial, chemical, and mechanical properties

The potential benefits of biodegradable and functional food packaging materials have garnered increasing attention in recent years. Sodium alginate (SA), a commonly utilized polysaccharide, is particularly noteworthy for producing biodegradable films for food packaging. This study aimed to investigate SA-based edible films enriched with various proportions of cactus pear peel extract (CPPE). We assessed the films and extracts for total phenolic content, antimicrobial and antioxidant activities, as well as mechanical properties. Cactus pear peels powder (CPPP) exhibited higher contents of total polyphenols (1243.82 mg GAE/100 g), total flavonoids (18.92 mg QE/100 g), and betalains (2.28 mg/100 g). The main constituents detected were catechol, pyrogallol, catechin, and alpha-coumaric acid, with concentrations of 1013.82, 223.45, 148.21, and 101.02 ppm, respectively, contributing about 45.71%, 9.85%, 6.54%, and 4.46% of the total phenolic compounds. The thickness of the SA films increased from 0.220 mm to 0.265 mm. The tensile strength values ranged from 1.98 to 3.12, while the elongation at break values for SA-CPPE films decreased relative to the plain SA film. Moreover, the inclusion of CPPE improved the barrier characteristics (with water vapor permeability values for SA films with 1%, 2%, and 3% CPPE ranging from 0.72 × 10−5 g·h−1·m−1·Pa−1 to 1.68 × 10−5 g·h−1·m−1·Pa−1) and induced variations in flexibility and resistance. The plain SA film did not exhibit any inhibitory activity against bacteria and fungi. However, the inclusion of CPPE in alginate films showed favorable antibacterial properties, which improved progressively with increasing CPPE concentration. These findings highlight the potential of incorporating active alginate-based films in food preservation.

Sustainable materials for novel food packaging based on alginate, methylcellulose and glycerol films functionalized with gallic acid

In the last years, new sustainable materials have been explored as plastic replacement in food industry. With the objective of developing sustainable active materials for food packaging, polysaccharide-based films: alginate, methylcellulose and glycerol-based films (ALG-MC-GLY (65:30:5)) were formulated and functionalized with different concentration of gallic acid (0.1, 0.5 and 0.8 % w/v). The mechanical, physicochemical, optical and functional properties of the films were evaluated. The incorporation of gallic acid resulted in films less resistant to tensile stress and less elastic, exhibiting reduced water vapor permeability. The physico-mechanical characterization was corroborated by FTIR spectra, HRSEM imaging and BET analyses, which demonstrated the interactions between the polymeric chains and gallic acid through localized hydrogen bonding, leading to denser structures with increased brittleness at higher concentrations of gallic acid. Moreover, the films functionalized with gallic acid displayed enhanced antioxidant properties in a concentration-dependent manner. These findings suggest that the ALG-MC-GLY based films loaded with gallic acid hold significant promise as alternative active food packaging materials.

Antimicrobial gelatin-based films with cinnamaldehyde and ZnO nanoparticles for sustainable food packaging

Cinnamaldehyde (CIN), a harmless bioactive chemical, is used in bio-based packaging films for its antibacterial and antioxidant properties. However, high amounts can change food flavor and odor. Thus, ZnO nanoparticles (NPs) as a supplementary antimicrobial agent are added to gelatin film with CIN. The CIN/ZnO interactions are the main topic of this investigation. FTIR-Attenuated Total Reflection (ATR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) were utilized to investigate CIN/ZnO@gelatin films. Transmission electron microscope (TEM) images revealed nanospheres morphology of ZnO NPs, with particle sizes ranging from 12 to 22 nm. ZnO NPs integration increased the overall activation energy of CIN/ZnO@gelatin by 11.94%. The incorporation of ZnO NPs into the CIN@gelatin film significantly reduced water vapour permeability (WVP) of the CIN/ZnO@gelatin film by 12.07% and the oxygen permeability (OP) by 86.86%. The water sorption isotherms of CIN/ZnO@gelatin were described using Guggenheim-Anderson-de Boer (GAB) model. The incorporation of ZnO NPs into the CIN@gelatin film reduced monolayer moisture content (M0) by 35.79% and significantly decreased the solubility of CIN/ZnO@gelatin by 15.15%. The inclusion of ZnO into CIN@gelatin film significantly decreased tensile strength of CIN/ZnO@gelatin by 13.32% and Young`s modulus by 18.33% and enhanced elongation at break by 11.27%. The incorporation of ZnO NPs into the CIN@gelatin film caused a significant decrease of antioxidant activity of CIN/ZnO@gelatin film by 9.09%. The most susceptible organisms to the CIN/ZnO@gelatin film included Candida albicans, Helicobacter pylori, and Micrococcus leutus. The inhibition zone produced by the CIN/ZnO@gelatin film versus Micrococcus leutus was 25.0 mm, which was comparable to the inhibition zone created by antibacterial gentamicin (23.33 mm) and cell viability assessment revealed that ZnO/CIN@gelatin (96.8 ± 0.1%) showed great performance as potent biocompatible active packaging material.

Biodegradable packaging paper derived from chitosan-based composite barrier coating for agricultural products preservation

Development of green packaging materials is essential to replace traditional plastics in fresh agricultural products preservation. Herein, a coated paper was designed by applying chitosan-based composite coating on paper substrate through a facile automatic coating method. The hydroxypropyl trimethyl ammonium chloride chitosan (HACC) was obtained by direct quaternization via the introduction of hydroxypropyl trimethyl ammonium chloride into the amino group of chitosan, then mixed with polyvinyl alcohol (PVA) to prepare the HACC/PVA coating. Accordingly, the key performance of coated paper were improved ascribed to the synergy effect of HACC/PVA coating and paper substrate. In particular, the minimum oxygen permeability of the coated paper could reach to 0.87 × 10−13 cm3·cm/cm2·s·Pa, and the optimum water vapor permeability and tensile strength of HACC/PVA coated paper was 0.75 × 10−12 g·cm/cm2·s·Pa and 6.88 kN/m, respectively. The coated paper used as packaging material not only reduced weight loss ratio of strawberry and greengrocery, but also exhibited lower chromatic aberration and better sensory evaluation, indicating a favorable effect on fruit and vegetable storage. Taken together, the designed eco-friendly coated paper has shown tremendous potential for green and biodegradable packaging material in agricultural products preservation.

Enhanced functional pectin films incorporated with olive fruit extracts prepared by deep eutectic solvents

The effect of olive extracts extracted with deep eutectic solvent (DES: choline chloride/glycerol, dl-malic acid/sucrose/glycerol, and citric acid/glycerol, respectively) on the structure, physical properties, and functional activities of pectin films, using DES both as a plasticizer and an extraction medium were explored. The findings revealed the integration of DES as a plasticizer was observed to increase film’s water vapor permeability and elongation at break, while concurrently diminishing its opacity. Furthermore, the incorporation of DES-olive extracts significantly enhanced the tensile strength, moisture barrier property, and opacity of the film, as well as improved its antioxidant and antibacterial activities. The structural analysis indicated the interaction among DES, olive extracts, and pectin facilitated the development of more ordered structures within the films, thereby improving the thermal stability of the pectin-based films. In conclusion, pectin active films using DES as a solvent and plasticizer have the potential to be used to improve antimicrobial and antioxidant packaging materials along with acceptable water resistance.

Methods for Fabrication of Self/Free Standing Nanocellulose (NC)-Nano Montmorillonite (N-MMT) Composite Films/Sheets — A Review

Plastic pollution looms large as a formidable foe to the environment. Enter cellulose nanofibers, the shining stars in the quest for innovative, eco-friendly paper-based packaging that is not just renewable, but also recyclable and biodegradable. These cellulose wonders boast impressively low oxygen permeability, but when it comes to water vapor, they fall short compared to traditional packaging plastics like LDPE. To tackle this challenge, researchers have been crafting composites by blending cellulose nanofibers with inorganic nanoparticles, such as Montmorillonite clay, which helps to curb water vapor permeability. However, this clever addition comes with a catch — it further complicates the already tricky drainage process during layer formation via vacuum filtration. This review delves into the complex world of nano cellulose-nano-MMT (Montmorillonite) composites, examining their preparation processes, unique characteristics, wide-ranging uses, and their significant contribution to promoting circular economy principles. By combining cellulose nanomaterials with MMT, a synergistic approach is taken to develop a new composite material with improved mechanical, thermal, and barrier properties. Various fabrication techniques are explored, including solution blending, in-situ polymerization, and electrospinning, allowing for customized design and optimization of the composite material. The review discusses how the nano cellulose-MMT composite demonstrates enhanced mechanical strength, thermal stability, and barrier properties, positioning it as a sustainable option compared to traditional materials. The review also showcases the diverse applications of these nano-composites in fields like packaging, biomedical devices, and environmental cleanup, emphasizing their alignment with circular economy principles. By examining the entire life cycle of these composites, from production to use and eventual disposal or recycling, the review underscores their role in supporting a circular economy. In light of the ongoing efforts by the scientific community and various industries to identify environmentally sustainable solutions, it is imperative to comprehend the synthesis, properties, and applications of nano cellulose-MMT composites. This understanding is essential for advancing sustainable processing for green material development.

Valorization of okara by-product for obtaining soluble dietary fibers and their use in biodegradable carboxymethyl cellulose-based film

In the face of mounting environmental concerns and the need for sustainable innovation, the use of agro-industrial wastes as raw materials offers a promising pathway. In this context, this study investigated the okara, a by-product of soy processing, as a novel source of soluble dietary fiber for the enrichment of carboxymethyl cellulose (CMC) biodegradable films based on environmental benefits of waste reduction with the creation of renewable packaging alternatives. Okara soluble dietary fiber (OSDF)-enriched CMC film was compared with films made from traditional and innovative soluble dietary fibers, such as pectin, inulin, and β-glucan. OSDF was obtained through acid hydrolysis at 121 °C, achieving a yield of 5.31 % relative to its initial dry weight. All the produced films exhibited a maximum crystallinity of 5 %, as revealed by X-ray diffraction (XRD), indicative of their largely amorphous structure, while scanning electron microscopy (SEM) ensured their uniformity and flawlessness. The CMC film enriched with okara soluble dietary fiber exhibited key properties, such as thickness, water vapor permeability, and thermal stability, comparable to other soluble fibers studied. These characteristics are essential for effective packaging applications. A notable distinction of the OSDF-enriched film was its capacity to block UV light, offering protection for light-sensitive items. The solubility tests showed that okara and β-glucan contributed to films with a higher solubility percentage. Mechanical testing underscored the influence of fiber on tensile strength, with the film enriched with β-glucan outperforming others at 27.5 MPa. All films showed rapid biodegradation within one week, emphasizing their eco-friendliness and the study alignment with sustainable development objectives in packaging.

Design and Characterization of an Antimicrobial Biocomposite for Wound Dressings.

Skin wounds, due to their high vulnerability to infections, represent a significant public health issue. These wounds are not only disabling but also entail costly treatments and slow recovery. Consequently, it is crucial to implement new treatments based on bioactive and natural antimicrobial compounds utilizing fibers, polymers, hydrocolloids, and hydrogels to control potential infections and promote wound healing. This study aimed to develop a biocomposite with antimicrobial activity for the treatment of skin wounds, using sodium alginate, bamboo fiber, and a natural antimicrobial as ingredients. The physico-mechanical properties (Young's modulus, tensile strength, elongation at break, moisture absorption, and water vapor permeability) and antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Staphylococcus hominis were determined. The results demonstrated that the designed biocomposite possesses adequate physico-mechanical properties, such as flexibility, strength, and water absorption capacity, in addition to exhibiting antibacterial activity, making it suitable to be used as a dressing in wound treatment.

Enhancing eco-friendly coatings: Aqueous olive leaves extract fortifies macroalgae-based packaging materials

This study incorporated bioactive compounds extracted from olive leaves (Olea europaea L.) into biodegradable films designed for preserving perishable food items like fruits and vegetables. Olive leaves, sourced from Lesvos island in Greece, yielded three aqueous extracts - OL1, OL2, and OL3 – representing different cultivated species. The antioxidant potential and phenolic compound profile of these extracts were analyzed. Subsequently, these extracts were integrated into 2% sodium alginate solutions, and the resulting mixtures were cast into 90 mm Petri dishes to form solid biofilms. Our findings reveal that the olive leaf extracts offer protection against UV–VIS radiation. Particularly, OL1 showcased the highest antioxidant capacity among the extracts examined. For the solid biofilms, various physical characteristics such as weight, diameter, density, and thickness were measured, alongside evaluating humidity, solubility in water, and water vapor permeability. The rheological properties of these solutions, influenced by temperature and extract addition, affect the viscosity, flow behavior, and gelation capacity, crucial for coating applications. Our research not only explores the impact of olive leaf extracts and glycerol as a plasticizer on biofilm solutions but also sheds light on increased opacity, reduced light absorption, and altered rheological properties. This endeavor aligns with the ongoing pursuit of sustainable packaging alternatives, emphasizing the crucial role of bioactive compounds in enhancing the functionality and eco-friendliness of biodegradable films.

Spider web-reinforced chitosan/starch biopolymer for active biodegradable food packaging

In this study, starch (ST), chitosan (CH), spider silk (SW), and their hybrid composite bioplastics were fabricated and examined for physicochemical and mechanical properties. The essential oils (EOs) of Rosmarinus officinalis were encapsulated to enhance their biological application. The prepared composite films were characterized using various spectroscopic techniques such as XRD, SEM, GCMS–, UV–VIS, TGA, and FTIR spectroscopy. The antimicrobial activity of the prepared film was tested against S. aureus bacterial and C. albican fungal strains which showed a greater zone of inhibition for the composite film encapsulated with EOs. The biodegradability of the synthesized film was evaluated for 60 days in soil under laboratory conditions. The composite film containing spider web and essential oil significantly improved mechanical properties. The physicochemical results, such as moisture, solubility, swelling, transmittance, opacity, and water vapor permeability, of the prepared bioplastic were comparable with those of the control plastic. The EO-based film had greater antioxidant activity against DPPH, hydrogen peroxide, and phosphomolybdenum assays, with an inhibition range of 60–70 %. The addition of spider web and essential oil to the chitosan/ starch film significantly increased the shelf life of injera and tomatoes for 7 and 10 days, respectively for the EO-based film. The biodegradability of the synthesized film has shown a great reduction in the weight and growth of microorganisms. In general, the CH/ST/SW and CH/ST/SW/EOs composite films have greater mechanical, biological, physicochemical, and potential improvement of food shelf life applied as either coating or packaging material.

Controlled localization of graphene oxide to improve barrier, biodegradation and mechanical properties of PBAT/EVOH

AbstractIncorporating graphene oxide (GO) with controlled localization into poly(butylene adipate‐co‐terephthalate) (PBAT) blends with poly(ethylene vinyl alcohol) (EVOH) aimed to improve barrier properties, biodegradability, and mechanical strength of PBAT. The PBAT/EVOH/GO nanocomposites containing 0 to 1 wt% of GO were prepared by a reactive mixing process in internal mixer. Microscopic images confirmed that the GO nanoplatelets are mainly localized in PBAT phase and then at the interface, contrary to the thermodynamic affinity of GO toward EVOH. The reactive nature of PBAT/EVOH/GO nanocomposites was confirmed via time‐sweep rheological studies where specific changes were observed in melt viscosity over time. The results of microscopic studies, rheometry, tensile test, and dynamic mechanical thermal analysis (DMTA) confirmed that localizing GO at the interface establishes strong interactions between PBAT and EVOH. By the addition of 0.75 wt% GO, tensile and yield strength were improved by 19% and 45%, respectively. Increasing GO significantly increased the hydrolysis degradation rate of the nanocomposites. Furthermore, the addition of GO considerably decreased the oxygen and water vapor permeability of the blends by up to 40% at 1 wt% GO.

Effect of Different Ratios of Polyvinyl Alcohol‐Gum Odina for the Preparation and Characterization of Biodegradable Composite Films

ABSTRACTThis research investigates the production of biodegradable films using a combination of gum odina (GO) and polyvinyl alcohol (PVA) with varied ratio. The study focuses on the chemical, physical, and mechanical properties of PVA‐GO composite films, emphasizing how versatile and biodegradable they may be for a range of packaging applications. Solvent‐cast PVA‐GO films with different ratios are subjected to a methodical analytical process to determine several parameters like mechanical qualities, thermal stability, biodegradability in soil, contact angle, transparency, water vapor permeability, moisture content, thickness, density, water solubility, microstructure, and FTIR analysis. The outcomes demonstrate that GO improves UV barrier qualities and water vapor permeability. Additionally, the films showed notable biodegradability, acceptable thermal stability, and mechanical qualities. In short, PVA‐GO films can provide an eco‐friendly packing substitute with adaptable qualities fit for a range of uses. Therefore, this research may further contribute promising information in the field of biodegradable packaging materials in the future.

Stretchable Composite Films Are Prepared by Using Cellulose Pulp with Differential Substitution of Carboxymethyl Cellulose and Thymol with an Infrared Heating Process for Packaging Application.

Herein, cellulose pulp (CP), carboxymethyl cellulose (CMC), and thymol-based eco-friendly, transparent, and flexible composite films are prepared. These materials dissolved well in an environment-friendly process in N-methyl morpholine N-oxide (NMMO) ionic liquids using infrared heating. Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses are used to study the structure, microstructure, and morphology of the composite films. The thermal properties of the CP/CMC/thymol composites are thoroughly studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The thermal stability of the composites (T 5%-57.8-91.2 °C and T 10%-216.6-284.1 °C) significantly improves following the CMC addition. In each case, all the composite film exhibits unique T g (140.5-143.1 °C) values, as confirmed by DSC. The tensile strength of the cellulose pulp is 66.5 MPa, increasing to 78.4 MPa for the CP/CMC-1:0.5 composites and steadily increasing to 93.8 MPa with increasing CMC content. Similarly, CMC increases the EB of cellulose pulp from 9.3 to 7.4%. The water vapor permeability and swelling ratio values of the CP/CMC/thymol composites are in the range of 1.9-2.11 × 10-9 g/(m2·Pa·s) and 52.5-50.8° respectively. The CP, CMC, and thymol-based composite do not exhibit cytotoxicity to the aneuploid immortal keratinocyte cell line and demonstrate excellent antioxidant properties, for promising packaging and biomedical applications.

Characteristics and properties of co-precipitated protein and film based on Bambara groundnut protein isolate and fish skin acid-soluble collagen

Co-precipitated protein (CPP) from Bambara groundnut protein isolate (BGPI) and fish skin acid-soluble collagen (ASC) at different BGPI/ASC ratios (100:0, 75:25, 50:50, 25:75 and 0:100 (v/v)) were prepared and characterized. CPP of BGPI/ASC at ratio of 75:25 had higher solubility at acidic and alkaline pHs, compared to other CPP samples. All CPPs had good emulsifying properties. Based on protein patterns, the combination of major bands from BGPI and ASC in the resulting CPP sample was observed. CPP with BGPI/ASC at ratio of 75:25 showed higher surface hydrophobicity than those of other CPP samples. When the films from CPPs were fabricated, similar tensile strength (p > 0.05) was observed, regardless of BGPI/ASC ratios. Nevertheless, film from CPP with BGPI/ASC ratio of 25:75 had higher elongation at break along with lower water vapor permeability (p < 0.05), compared to other CPP films. All CPP films had bright-yellowish color. Increasing ASC ratio augmented (p < 0.05) light transmission of resulting CPP films. FTIR spectra revealed that all CPP films had the similar pattern and functional groups. Therefore, the co-precipitated BGPI and ASC at appropriate ratio could improve properties of resulting proteins, especially for film forming ability.

Tailoring the size and shape of PbWO4 particles in highly filled polymer fibers for γ‐rays shielding

AbstractHighly filled polymer fibers offer huge promise for radiation protection safety and wear comfort of personal protective equipment (PPE) in radiation environments. However, it usually sacrifices mechanical properties that directly related to practical usability. Here, as high as 75 wt% PbWO4 (PWO) particles have been filled in polyvinyl alcohol (PVA) fiber via tailoring their size and shape for enhanced γ‐rays shielding and good mechanical properties. Clearly shown that 0 dimensional (0‐D) PWO exhibits better dispersion and compatibility between the interfaces than 1‐D PWO in highly filled PVA fibers. In addition, 70 wt% 0‐D PWO/PVA fibers display better mechanical properties than 70 wt% 1‐D PWO/PVA fibers. Note that 75 wt% 0‐D PWO/PVA fibers show 1.02 cN/dtex of tensile strength. However, 75 wt% 1‐D PWO/PVA fibers fail to be fabricated smoothly. Importantly, the overlapped fabrics with 75 wt% 0‐D PWO/PVA fibers display 43.05% of γ‐ray shielding (105 keV) meanwhile it offers good air and water vapor permeability for wear comfort. The superior γ‐ray shielding ascribes the polymer fibers with the higher filling in comparison with its counterpart, which provides a practical means to design radiation protection safety and wear comfort of articles.Highlights This work breaks the upper limit of filling in polymer fibers Filler structure can weigh the integrated properties of polymer fibers. 0‐D PWO particles promote interfacial compatibility in highly filled fibers. Radiation protection safety and wear comfort of articles tend to be designed.

Fabrication and characterization of novel biodegradable films based on tomato seed mucilage and gelatin plasticized with polyol mixtures

This research evaluates the potential of tomato seed mucilage (TSM) –gelatin (Ge) in producing edible films. Edible films were made using various ratios of TSM to Ge (1:0, 0.33:0.66, 0.66:0.33, and 0:1). Moreover, the effects of including three types of plasticizers, namely, glycerol (Gly), sorbitol (Sor), and polyethylene glycol (PEG) were investigated. The findings indicated that adding Ge did not affect the thickness of the films (p>0.05). However, it significantly increased the tensile strength (TS) and Young's modulus while reducing the elongation at break (EB) (p˂0.05). A higher TSM ratio significantly increased total color difference (ΔE) and yellowness index while decreasing film lightness and whiteness index (WI) (p˂0.05). The contact angle significantly decreased with the TSM ratio increases and Ge decreases (p˂0.05). Moreover, this led to higher opacity, solubility, moisture content, oxygen permeability, water vapor permeability (WVP), swelling, and moisture absorption (p˂0.05). Adding a plasticizer had no effect on the films' opacity, contact angle, and thickness. The Gly-containing film featured the highest EB, solubility, moisture content, swelling, WVP, oxygen permeability, and moisture absorption. The Sor-containing film had the highest TS. TSM concentration was directly correlated with increased film heterogeneity and surface roughness. X-ray diffraction peaks became sharper by increasing TSM concentration and including PEG, while Gly inclusion produced ordered broad peaks.

Preparation and characterization of intelligent packaging labels based on pea starch, κ-carrageenan and black raspberry extract for monitoring freshness of pork

Intelligent biodegradable packaging has gained significant attention recently due to its great potential for food freshness monitoring. In this study, we developed intelligent labels using pea starch (PS), κ-carrageenan (KC) and black raspberry extract (BRE) and evaluated their physicochemical properties and effectiveness in pork freshness monitoring. Incorporation of KC significantly decreased tensile strength (TS) (33.43 to 19.84 MPa) and increased elongation at break (EAB) (6.26 to 7.41 %) and water vapor permeability (WVP) (2.11 to 2.48 × 10−9 g m−1 s−1 Pa−1) of PS label. Incorporation of BRE significantly decreased WVP (2.48 to 1.96 × 10−9 g m−1 s−1 Pa−1) and increased TS (19.84 to 29.68 MPa) and EAB (7.41 to 11.09 %) of PS-KC label. PS-KC-BRE labels showed increased light barrier performance, thermal stability, antioxidant activity, pH and ammonia sensitivities, and significant visible color change as pH indicators. Findings suggest PS-KC-BRE labels can be used as intelligent packaging in food industry.

Fabrication and characterization of bioactive curdlan and sodium alginate films for enhancing the shelf life of Volvariella volvacea

This study aimed to develop bioactive films based on curdlan (CD) and sodium alginate (SA) to enhance the shelf life of the Volvariella volvacea mushroom. A stable nanoemulsion of droplet size of 150.1 ± 5 nm was first formulated using 5% soy protein (Sp) and 10% lavender essential oil (LEO), achieved by ultrasound treatment for 10 min, resulting in small droplet sizes. In parallel, a CD-SA film was prepared by mixing them in a 1:1 ratio. The SpLEO nanoemulsion was then ex situ added to the CD-SA film at varying concentrations (4%, 6%, 8%, and 10%). The resulting bioactive film exhibited desirable properties, including water vapor permeability (1.15 ± 0.05 × 10−10 g m−1 Pa−1 s−1), swelling rate (547%), and tensile strength (10.1 ± 1.3 MPa). Docking and structural analyses suggested that ultrasound treatment enhanced the intermolecular hydrogen bonding, creating a uniform and regular surface and reduced crystallinity. The CD-SA film with ultrasound-treated 8% SpLEO nanoemulsion [i.e., (CD-SA/SpLEO-8)US] showed antibacterial activity against Escherichia coli and Staphylococcus aureus and extended the freshness of straw mushrooms prevention of spoilage during storage. Additionally, the film reduced respiration rate (975 mg CO₂/kg/h at 96 h) and ethylene production (160 ng/kg/s by 96 h) while effectively inhibiting straw mushroom autolysis. This led to a reduction in browning (2.91), total soluble solids (7.5%), weight loss (13.9%), and polyphenol oxidase activity (0.08 ΔOD420/min⋅g), thereby extending the shelf life of the mushrooms to 96 h. These findings highlight the potential of incorporating different molecules using ultrasound treatment to develop innovative edible films for food preservation.

Dual cross-linked network of the active starch film by incorporating palmitic acid and geraniol: A comprehensive evaluation of the hydrophobic mechanism and antimicrobial activity

In this study, (3-Aminopropyl) triethoxysilane (APTES) was employed as a bridging agent to enhance the compatibility between the hydrophilic starch/pectin film and the hydrophobic palmitic acid (PA) coating through hydrogen bonding and chemical reactions. To address the insufficient antibacterial activity of starch films, geraniol was also incorporated. The intermolecular interactions among APTES, PA, and starch were confirmed using x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and hydrogen nuclear magnetic resonance spectroscopy (1H NMR). Notably, the inclusion of APTES and PA significantly increased the film's hydrophobicity, resulting in a water contact angle (WCA) of 95.12°, a water vapor permeability (WVP) of 2.08 × 10−10 g/(mm·s·Pa), and an oxygen permeability (OP) of 2.61 × 10−9 g·mm·mm−2·s−1. Molecular dynamics (MD) simulations revealed strong non-covalent interactions and exceptional compatibility between starch and PA. Furthermore, the integration of pectin and geraniol improved the mechanical strength and antimicrobial properties of the modified films compared to unmodified starch films. These environmentally friendly and biodegradable starch-based films present a promising option for sustainable packaging materials in food preservation.

The Effects of Polyester Filament Number and Accompanying Hydrophilic Fiber Type on Moisture Management and Drying of Double-Layered Knitted Fabrics

This study aims to investigate the moisture transfer and drying behavior of the double-layered fabrics knitted using polyester yarns with a combination of cotton and viscose yarns. As well as the fiber type on both faces, the effect of the number of filaments of the polyester yarns was also researched. For this purpose, double-layered interlock fabrics were knitted, and the resultant samples were characterized by moisture management, drying, water vapor permeability, and heat conduction tests. It was indicated that the fabrics knitted by polyester yarns on the inner side and cotton fabrics on the outer side resulted in a very good overall moisture-management capacity. The same applied to the drying speed; even faster drying was achieved than the 100% polyester double-layered samples. The increase in the filament number led to a decrease in both moisture management and drying rate. Moreover, it was determined that the use of viscose yarn was not suitable.