Water Vapor Permeability Values Research Articles

A visual bi-layer sensor based on Agar/TiO2/butterfly bean flower anthocyanin/κ-carrageenan with photostability for monitoring Penaeus chinensis freshness

Visual indicator bi-layer films were manufactured incorporating κ-carrageenan, butterfly pea flower anthocyanin, varying Nano‑titanium dioxide (TiO2) content and agar for Penaeus chinensis (Chinese white shrimp) freshness detection. The κ-carrageenan-anthocyanin (CA) layer served as indicator, while the TiO2-agar (TA) layer functioned as the protective layer to improve the photostability of film. The bi-layer structure was characterized by scanning electron microscopy (SEM). The TA2-CA film had the best tensile strength with a value of 17.8 MPa and the lowest water vapor permeability (WVP) value of bi-layer films was 2.98 × 10−7 g.m−1.h−1.pa−1. The bi-layer film protected anthocyanin against exudation when immersed in aqueous solution of varying pH. The TiO2 particles filled the pores of the protective layer, increasing the opacity from 1.61 up to 4.49 significantly improving the photostability with a consequent slight color change under illumination of UV/visible light. Under UV irradiation, the TA2-CA film had no significant color change with a ΔE value of 4.23. Finally, the TA2-CA films showed an obvious color change from blue to yellow green in the early stages of Penaeus chinensis putrefaction (≤48 h) then the color change and Penaeus chinensis freshness were well correlated (R2 = 0.8739).

Effects of fiber cross-section shape on thermal comfort properties of polyester interlock fabrics

In this study, some dimensional and thermal comfort properties, i.e. thermal resistance, water vapor permeability, and air permeability properties of interlock fabrics knitted from different cross-section shaped polyester fibers were investigated. Four polyester yarns of different fiber cross-section shapes (hollow-round, round, triangular, and W-shape) were used to produce the samples. From the results, it was found that the triangular and W-type fibers had higher fabric density values due to the denser and closer fiber settlement. The highest bursting strength value belonged to the sample knitted from hollow-round yarn, which had also the highest yarn-breaking load value. The samples knitted from both round cross-section polyester yarns had significantly higher air permeability and thermal resistance values than the other samples due to the lower fabric density values of these fabrics. On the other hand, the water vapor permeability values of the fabrics from triangular and W-type fibers were slightly higher than the others because of their lower thicknesses.

Optimization of Knitted Fabrics for better Thermo-Physiological Comfort by using Taguchi-based Principal Component Analysis

The water, air permeability and thermal resistance of fabrics are important attributes that have a significant impact on the thermal comfort properties of sportswear fabrics in different environmental conditions. In this work, terry and fleece fabrics were developed by varying the fibre content and mass per unit area of fabrics. Moreover, the thermo-physical properties of the developed fabrics, including air permeability, water vapor permeability and thermal resistance, were analysed before and after washing. The multi-response optimization of the thermal comfort properties of knitted fabrics was performed using principal component analysis (PCA) and the Taguchi signal-to-noise ratio (PCA-S/N ratio) to achieve optimal properties. It was determined that the selected parameters (fabric type, finishing, fibre content and fabric mass per unit area) had a significant effect on the thermal comfort properties of knitted fabrics. The PCA analysis showed that 100% cotton terry fabric before washing with an aerial weight of 220 g/m2 had higher air and water vapor permeability value, but a lower thermal resistance value.

Microwave-Treated Physically Cross-Linked Sodium Alginate and Sodium Carboxymethyl Cellulose Blend Polymer Film for Open Incision Wound Healing in Diabetic Animals-A Novel Perspective for Skin Tissue Regeneration Application.

This study aimed at developing the microwave-treated, physically cross-linked polymer blend film, optimizing the microwave treatment time, and testing for physicochemical attributes and wound healing potential in diabetic animals. Microwave-treated and untreated films were prepared by the solution casting method and characterized for various attributes required by a wound healing platform. The optimized formulation was tested for skin regeneration potential in the diabetes-induced open-incision animal model. The results indicated that the optimized polymer film formulation (MB-3) has significantly enhanced physicochemical properties such as high moisture adsorption (154.6 ± 4.23%), decreased the water vapor transmission rate (WVTR) value of (53.0 ± 2.8 g/m2/h) and water vapor permeability (WVP) value (1.74 ± 0.08 g mm/h/m2), delayed erosion (18.69 ± 4.74%), high water uptake, smooth and homogenous surface morphology, higher tensile strength (56.84 ± 1.19 MPa), and increased glass transition temperature and enthalpy (through polymer hydrophilic functional groups depicting efficient cross-linking). The in vivo data on day 16 of post-wounding indicated that the wound healing occurred faster with significantly increased percent re-epithelialization and enhanced collagen deposition with optimized MB-3 film application compared with the untreated group. The study concluded that the microwave-treated polymer blend films have sufficiently enhanced physical properties, making them an effective candidate for ameliorating the diabetic wound healing process and hastening skin tissue regeneration.

Starch-based environment friendly, edible and antimicrobial films reinforced with medicinal plants.

In the current study, cornstarch-based antimicrobial and edible films were designed using solution-casting methods. The medicinal plants (Acontium heterophyllum, Artemisia annua, and Thymus serpyllum) reinforced the gelatinized solution in different concentrations as fillers. The effect of plant extracts on antimicrobial and antioxidant potential, microstructure, barrier, thermal and mechanical properties of cornstarch-based films (SBFs) was investigated using antimicrobial activity, DPPH free radical scavenging values, scanning electron microscopy, X-ray diffraction, water vapor transmission rate, differential scanning calorimetry, and tensile strength. Likewise, it was depicted that the geometric and crystalline structures of medicinal plants' reinforced films remained the same even after processing. The mechanical tests indicated that the plant extracts effects are associated with reduced elongation, increasing tensile strength, and Young's modulus. Morphological analysis revealed the generation of uniform and the compact surfaces. However, films with 10% concentration of plant extracts have the lowest water vapor permeability values, and emerged better barrier properties. Moreover, these films showed the significant antioxidant potential and antimicrobial activity.

Synthesis and Characterization of Sweet Potato Starch Biocomposite Incorporated with ZnO Nanoparticles

The rapid rise in the production of hazardous waste in the environment, particularly single-use plastics, has prompted the development of sustainable yet cost-effective alternatives. This research aims to create bioplastic films using renewable energy sources. To prevent toxic side products, the composite bioplastics synthesized from sweet potato starch are incorporated with biogenically synthesized ZnO NPs. Biocomposite films were characterized by their morphology, water vapor permeability (WVP), biodegradability, thermal and mechanical properties. It was noted that the ZnO NPs had substantial effects on the tensile properties of the nanocomposite films. The addition of ZnO NPs to the starch bioplastic films considerably enhanced tensile strength from 1.41 to 2.26 MPa, elongation from 78.20 to 114.91%, and Young’s modulus from 1.62 to 2.40 MPa. The incorporation of ZnO NPs lowered the degree of WVP and film solubility value compared to those of the starch films. The bioplastic film incorporated with ZnO NPs had effective UV absorption and transparency. The shift in the peaks in the FT-IR spectra confirmed the relationship between the polymer matrix and the ZnO NPs. Thermal degradation of bio nanocomposite at 339.60 and#176;C is shown by a consistent reduction in TGA between 240 and#176;C and 410 and#176;C. The high melting temperature (Tm) of 144 oC for starch film and 201.86 oC for bio nanocomposite was found using DSC analysis. SEM analysis revealed that biocomposite films had better compatible morphologies with small cracks and the roughness of films increased with the addition of ZnO NPs content. The biodegradability of the biocomposite films was analyzed through the soil burial method. The bioplastic produced in this study has the potential to be a viable alternative to existing conventional plastics in the packaging industry.

Efekat šelak smole na osobine zeinskog filma

In this paper, zein-based films with the addition of shellac were synthesized by lamination on the existing dry zein film (L samples) and by adding shellac alcohol solution during the synthesis of zein film in a ratio of 50-50 by casting process (M samples). Zein films without the addition of shellac were designated as control samples. Physico-chemical (thickness, moisture content and solubility), mechanical (tensile strength and elongation at break) and barrier characteristics (water vapor permeability) were examined for all samples. The resulting films were transparent, glossy, light yellow (control) to ocher (samples with shellac), flexible, and non-sticky. The results showed significantly higher values of elongation at the break of the samples with shellac (11.49% for M and 18.99% for L) compared to the control (7.14%). Significantly lower water vapor permeability values were found, 10.04 g/(m²ꞏh) for L, and 18.41 g/(m²ꞏ h) for M, compared to the control pure zein film (40.33 g/(m² ꞏh)).

Poly(ethylene oxide)-Based Copolymer-IL Composite Membranes for CO2 Separation.

Poly(ethylene oxide) (PEO)-based copolymers are at the forefront of advanced membrane materials for selective CO2 separation. In this work, free-standing composite membranes were prepared by blending imidazolium-based ionic liquids (ILs) having different structural characteristics with a PEO-based copolymer previously developed by our group, targeting CO2 permeability improvement and effective CO2/gas separation. The effect of IL loading (30 and 40 wt%), alkyl chain length of the imidazolium cation (ethyl- and hexyl- chain) and the nature of the anion (TFSI-, C(CN)3-) on physicochemical and gas transport properties were studied. Among all composite membranes, PEO-based copolymer with 40 wt% IL3-[HMIM][TFSI] containing the longer alkyl chain of the cation and TFSI- as the anion exhibited the highest CO2 permeability of 46.1 Barrer and ideal CO2/H2 and CO2/CH4 selectivities of 5.6 and 39.0, respectively, at 30 °C. In addition, almost all composite membranes surpassed the upper bound limit for CO2/H2 separation. The above membrane showed the highest water vapor permeability value of 50,000 Barrer under both wet and dry conditions and a corresponding H2O/CO2 ideal selectivity value of 1080; values that are comparable with those reported for other highly water-selective PEO-based polymers. These results suggest the potential application of this membrane in hydrogen purification and dehydration of CO2 gas streams.

Development and properties of wheat straw nano-holocellulose and reduced graphene oxide composite films for active packaging materials

The nano-holocellulose was obtained from wheat straw, and a series of composite films were prepared from the nano-holocellulose and reduced graphene oxide by vacuum filtration. The properties of the resultant rGO/nano-holocellulose films were researched, including morphology, XRD analysis, mechanical properties, UV-Vis transparency, contact angle, water vapor permeabilities, swelling properties, thermogravimetric analysis, and electrical conductivity. The results demonstrated that the tensile properties of the films were augmented by 639.8 %, as high as 88.70 MPa with the 8 % content of the rGO. The maximum UV transmittances of the 10 % rGO-Film in the far ultraviolet region, the middle ultraviolet region, and the near-ultraviolet region were 0.1 %, 0.4 %, and 2.1 %, respectively, which could blocked the penetration of ultraviolet light to a great extent. In addition, the hydrophilicity, water vapor permeability value, and swelling ratio of the composite films were reduced, and moreover, the composite films were endowed with the ability to conduct electricity. Compared with the 0 % rGO-Film, the contact angle of the 10 % rGO-Film was increased by about twice, and the water vapor permeability value was decreased by 10.7 %. Furthermore, 10 % rGO-Film exhibited an approximately 25-fold in conductivity compared to 1 % rGO-Film. Therefore, the nano-holocellulose based composite films have good application prospects in biodegradable packaging materials. • The composite film was prepared by nano-holocellulose and rGO. • The composite film was obtained by the vacuum filtration. • The tensile and UV resistance properties of the films were greatly enhanced by rGO. • The films were endowed with electrical conductivity by the rGO. • The composite films could be applied in packaging materials.

Antibacterial poly(butylene succinate-co-terephthalate)/titanium dioxide/copper oxide nanocomposites films for food packaging applications

Titanium dioxide (TiO2)/copper oxide (CuO) nanoparticles (NPs) were synthesized by co-precipitation method. The photocatalytic activities of TiO2 were enhanced by the incorporation of CuO. The poly(butylene succinate-co-terephthalate) (PBST)-based nanocomposite (PTC) films were prepared via solvent casting method. Mechanical properties, UV-Vis light barrier, water vapor permeability (WVP), antibacterial properties, and preservation properties of composite films were evaluated. When the content of TiO2/CuO NPs was 3 %, the best overall properties of the film were obtained. The tensile strength and elongation at break reached maximum values of 35.6 ± 0.4 MPa and 590.7 ± 5.3 %, respectively. Meanwhile, the WVP values and UV-Vis transmittance of PTC-3 film decreased. The inhibition rates were close to 90 % against Staphylococcus aureus and Escherichia coli. Moreover, the PTC-3 film could extend the shelf life of cherry tomato after conducting preservation experiments for 18 days. Prepared PTC films had potential for food packaging.

The potential of chitosan-based film with curry leaf essential oil as natural insect-repellent food packaging

This research investigated the effect of curry leaf essential oil (CLEO) on the properties of chitosan-based film and its potential as a natural insect-repellent film. CLEO was added at different concentrations (0.5–1.5 %) with Tween 80 (0.1–0.3 %) as a surfactant. Chitosan-CLEO matrix films successfully reduced (p < 0.05) the moisture content, film water solubility and water vapor permeability values. The incorporation of Tween 80 at 0.3 % (of distilled water) further improved (p < 0.05) the film's moisture and water barrier. Films containing more CLEO showed higher total phenolic compound and antioxidant activity with the DPPH (2, 2-diphenyl-1-picrylhydrazyl) % increased significantly (p < 0.05) from 19.07 % to 33.67 %. The chitosan-CLEO film-forming emulsion (FFE) also inhibited the Gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) and Gram-negative bacteria (Escherichia coli and Salmonella typhimurium), indicating the potential of CLEO as antibacterial agents. Meanwhile, chitosan film incorporated with 0.5 % CLEO successfully repelled at least 60–70 % of Musca domestica in the area preference test, while the films enriched with 1.0 % CLEO and 0.3 % Tween 80 showed 100 % repellency. Repellency results are considered very promising for chitosan-CLEO films to develop as active packaging with a natural repellent effect.

Morphological and Mechanical Characterization of Films Incorporating Porphyran Extracted from Porphyra Dioica

This paper studies the effects of glycerol plasticizers and/or alginate, pectin, and carboxymethylcellulose polysaccharides on the mechanical and physical properties of porphyran-based films to evaluate the films’ ability to be used as food packaging. Films were characterized in terms of their composition, microstructural and morphological features, thermal properties, water interaction, and mechanical performance. All films are homogeneous, transparent, and slightly brownish in color. The structures are amorphous and crosslinked, showing the films’ thermoset nature. Moisture content and water solubility depend on the second polysaccharide added to the porphyran, but they both increase with the addition of glycerol to the formulations; water vapor permeability is strongly affected by the second polysaccharide in the formulation. The films display stiff and brittle mechanical behavior, but ductility increases significantly in formulations containing glycerol plasticizers. The barrier and mechanical performance values of the materials produced were found to be lower than those reported for commercial food packaging. The formulations containing glycerol displayed lower water vapor permeability values, ranging from 2.98 for porphyran/carboxymethylcellulose/glycerol to 6.65 mm·g·d−1·m−2·kPa−1 for porphyran/alginate/glycerol films. All films, except porphyran/glycerol and porphyran/alginate/glycerol, had ultimate tensile strengths above 10 MPa—the threshold value that ensures that a package is ductile enough to withstand handling and forming operations. Furthermore, the porphyran/pectin/glycerol and porphyran/carboxymethylcellulose/glycerol films displayed sufficiently high ductility values of 2.94 and 3.10%, respectively. These results indicate that the studied porphyran/pectin/glycerol and porphyran/carboxymethylcellulose/glycerol formulations have a combination of physical and mechanical properties that ensure adequate film integrity and function through the complete food packaging supply chain. The results here reported represent an opportunity to extend the scope of porphyran films to applications in the dry food packaging industry.

Bio-based poly(ethylene furanoate)/ZnO transparent thin films with improved water vapor barrier and antibacterial properties for food packaging application

Poly(ethylene furanoate) (PEF) biocomposite films incorporating zinc oxide nanoparticle (ZnO NPs) were prepared using a solvent casting method. The ZnO NPs were homogeneously dispersed within the PEF films with the aid of γ−aminopropyltriethoxylsilane (APTES). The water vapor barrier, optical transmittance and antimicrobial properties of the PEF/ZnO films were tested. Water vapor permeability (WVP) and transmittance in the visible (400–800 nm) region of control PEF film were 6.92 × 10–12 g·m m−2 · s·Pa and 87.3%, respectively. WVP value of PEF films decreased 43.2% through ZnO NPs compounding. On the contrary, transmittance of PEF films decreased 6.8% due to the absorption and scattering of ZnO NPs. In addition, the PEF film with modified ZnO NPs exhibited a bacteriostatic rate up to 97.0% after 3 h. Thus, the PEF/ZnO films show great potential in the field of food packaging.

Investigating Waterproofness and Breathability of a Coated Double-Sided Knitted Fabric

The demand for waterproof breathable fabrics is increasing globally and so are efforts to develop such garments. In this paper, the development of a waterproof breathable textile by coating a double face knitted fabric is described. The applied polymeric coating is a mixture of an acrylic paste and a fluorocarbon resin. The aim of this study was the investigation of the breathability and waterproofness of the coated samples. The coating was made of industrialized chemical products and did not require water use. The screen coating process wastewater was also reduced. Three parameters related to the coating process were analyzed and optimized. These parameters were the fluorocarbon resin quantity (%), acrylic paste quantity (g·m−2), and reticulation time (min). The analyzed responses were the air permeability, windproofness, water vapor permeability, and resistance to water penetration. The optimized values of air permeability and water vapor permeability were equal to 154.81 L·m−2·s−1 and 83.852%, respectively. These values were judged acceptable when compared with commercialized products. The windproofness and the resistance to water penetration were equal to 161.81 L·m−2·s−1 and 78.51 Schmerber, respectively. Thus, both responses still need to be improved in order to obtain waterproofness properties. Based on the obtained results, the coated fabric can be used as a laminate outer layer for producing waterproof breathable fabrics.

Biodegradable composite films based on Trigonella foenum‐graceum galactomannan—xanthan gum: Effect of grape seed oil on various aspects of emulsified films

AbstractNowadays, preparing biodegradable films based on hydrocolloids has become thoroughly crucial in food packaging. Also, to enhance some of the aspects of these films, adding oil to the formulation of the films has been considered as a valid method. In this study, a variety of films based on two biopolymers (fenugreek galactomannan and xanthan gum) in the presence or absence of grape seed oil were produced and the various aspects of the obtained films were comprehensively investigated. The obtained data demonstrated that preparing composite films based on two hydrocolloids improved the aspects including film thickness, water vapor permeability (WVP), oxygen permeability (OP), mechanical and thermal properties more than films based on only one hydrocolloid. This improvement was mostly related to the good and acceptable interaction between two biopolymers. The X‐ray diffraction (XRD) patterns indicated that all films had an amorphous or non‐crystalline structure. Also, the scanning electron microscope images demonstrated that films based on fenugreek galactomannan and composite films based on two hydrocolloids. The value of film thickness and strain at break (SAB) increased by adding oil to the formulation. Contrarily, the moisture content and absorption, WVP, OP, opacity, and ultimate tensile strength (UTS) values of the films decreased by adding oil.

Characterization of ionically crosslinked alginate films: Effect of different anion-based metal cations on the improvement of water-resistant properties

In general, calcium ions are widely used to crosslink alginate films for improved mechanical properties. But for the poor water resistance of the alginate films due to their hydrophilicity, various ion-crosslinking agents (CaCl 2 , FeCl 2 , FeCl 3 , and FeSO 4 ) were used to prepare alginate films, with an emphasis on cations (Ca 2+ , Fe 2+ , and Fe 3+ ) and anions (Cl − and SO 4 2− ) with different valences. Chemical, morphological, optical, and mechanical properties were evaluated to demonstrate their influences on ion-crosslinking. All crosslinked films exhibited higher tensile strength and lower elongation at break than the control alginate film. Optically, the films crosslinked with Fe ions showed a yellow appearance, while the CaCl 2 -crosslinked film showed no significant color difference from the alginate film. As for the water-resistant properties [moisture content, water solubility, water vapor permeability (WVP), and swelling index (SI)], the FeSO 4 -crosslinked film presented the lowest WVP value with the highest SI value than others, suggesting the possibility to WVP increase depending on the reaction time. Thus, we studied the effect of crosslinking time on the water resistance of films using CaCl 2 and FeSO 4 . The FeSO 4 -crosslinked film exhibited a significant decrease in WVP value with increased crosslinking time, an opposite trend from that of the CaCl 2 -crosslinked one. Because water vapor permeability is an important property of food packaging materials, FeSO 4 , which is generally recognized as safe (GRAS) but has rarely been studied as an ionic crosslinking agent for alginate, has a high potential to be used as such in alginate films. • Alginate was used as a polymer to produce biodegradable food packaging materials. • Three types of iron compounds (FeCl 2 , FeCl 3 , and FeSO 4 ) were used to crosslink alginate films. • FeSO 4 -crosslinked film indicated the lowest water vapor permeability compared to other films. • An increase in crosslinking time enhanced the water barrier properties of the FeSO 4 -crosslinked film. • FeSO 4 showed the greatest potential to replace CaCl 2 as a crosslinking agent of alginate film.

Efecto de la humedad relativa de almacenamiento sobre las propiedades fisicoquímicas de películas comestibles de almidón de maíz obtenidas por la combinación de la tecnología de extrusión y técnica de casting

Starch is one of the most used polysaccharides in the formulation of Edible Films (EFs). This work aimed to develop starch-based EFs employing extrusion technology as a pretreatment to casting technique and evaluate the storage relative humidity (RH) effect to determine their possible application as food coating. Corn starch and a mixture of plasticizers (sorbitol and glycerol) were processed in a twin-screw extruder. The casting technique was used for EFs formation. The EFs were conditioned at different storage RH (53, 75, and 100%) for ten weeks. The studied response variables were: puncture resistance (PR), puncture deformation (PD), water vapor permeability (WVP), water solubility (WS), X-ray diffraction patterns, and relative crystallinity. EFs at 53 and 75% RH showed the most stable behavior in PR and PD. Concerning the barrier properties, it was found that EFs stored at 53% RH had the lowest value of WVP and XRD patterns showing that storage time produces crystalline zones by the aging effect. Starch-based EFs obtained by the combination of extrusion-casting and stored at an RH of 53 and 75% presented the best physicochemical properties. Hence, these EFs could be used as coatings of intermediate moisture foods.

The effect of pine cone lignin on mechanical, thermal and barrier properties of faba bean protein films for packaging applications

In the present work, faba bean protein (FBP) films plasticized with glycerol and reinforced with different amounts (2.5, 5.0, 7.5 and 10% by weight of FBP) of lignin extracted from pine cones (PL) have been obtained by solution casting. The results obtained showed an elongation at break of 111.7% with the addition of 5% PL to the FBP film, which represents an increase of 107% compared to the FBP control film. On the other hand, it was observed by thermogravimetric analysis (TGA) that the incorporation of lignin improved the thermal stability of the FBP film, leading to an increase in the protein degradation temperature, being this increase higher in the sample film reinforced with 10% PL. The barrier properties of the FBP films were also affected by the presence of lignin, leading to a decrease in water vapor permeability (WVP) in comparison to the unreinforced film. The results show that the sample reinforced with 2.5% PL had the lowest WVP value, with a reduction of 25% compared to the control film. Chemical analysis by Fourier transform infrared spectroscopy (FTIR) confirmed the formation of intramolecular interactions between lignin and proteins which, together with the inherent hydrophobicity of lignin, resulted in a decrease of the moisture content in the films reinforced with PL. This research work has allowed the development of biobased and biodegradable films with attractive properties that could be of potential use in sectors such as packaging.

Parameters Affecting the Water Vapour Permeability of Gelatin Films as Evaluated by the Infrared Detecting Method ASTM F1249

The purpose of this study was to assess testing parameters for measurement of water vapour permeability (WVP) properties of bovine gelatin films by ASTM F1249. This method utilises an infrared sensor to determine the WVP of conventional plastic-based films and has been widely applied within the packaging industry, but has had very limited application with hydrophilic compostable/edible packaging materials. These films have low WVP properties with highly variable WVP values (as studied by ASTM E96); consequently, this parameter has to be carefully controlled. Assessment of the module was carried out using bovine gelatin films with different thicknesses of film, and gelatin was chosen as an example of such film types using the following Mocon Permatran testing parameters: 50 or 70% relative humidity (RH), 100 or 150 cm3 nitrogen gas flow rates for the module’s RH-cell (100 cm3 for all other cells). In all cases, WVP increased with an increase in gas flow rate. This method showed that WVP increased with increasing gelatin film thickness, and categorically supports previous—and often unexplained—WVP findings for other hydrophilic, biopolymer films. The current study is a helpful guide to the examination of water barrier properties of hydrophilic edible/biodegradable/compostable packaging materials in research and industry.

Effect of interactions of locust bean gum and rosehip juice on the physical properties of gum tragacanth composite films

The aim of the study was to demonstrate the synergistic effect of natural polysaccharide hydrocolloids of locust bean gum and tragacanth gum combined with rosehip juice. It was shown that tragacantha gum has an excellent film-forming properties at low concentration and forms water-soluble, thin and transparent edible films with high application potential, which was demonstrated by selected physical properties of composite films obtained from a mixture of gum tragacanth and locust bean gum. Optical (color and opacity), thermal (thermogravimetric analysis), water vapor permeability and sorption kinetics were determined. The thickness of the films depends on the composition of the films, the process conditions, as well as the application techniques. The addition of locust bean gum resulted in an increase in the water content and consequently more elastic and less brittle gum tragacanth films. Films made only of gum tragacanth were characterized by greater hygroscopicity, as opposed to composite films. As the concentration of gum tragacanth increases, the value of water vapor permeability also increases, and the share of locust bean gum in the films caused the permeability to decrease. Composite films had a lighter color compared to those of pure gum tragacanth, and the carob contributed to a more transparent film and slower thermal degradation. In the films obtained, a synergistic effect was observed between the biopolymers in all the ratios used, and the addition of locust bean gum and rosehip juice had a strong influence on the properties of the obtained edible films. Practical applications The potential of using gum tragacanth to create edible films and coatings through their appropriate modification and optimization of the composition ratio of the created composites can become a challenge for their use in the food packaging industry. This study will be constructive for further research work focused on films and coatings and their application as protective coatings or bio-based packaging films.