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Summary: The composite film with collagen as the main component has been widely used due to its characteristics of non‐toxicity, environmental protection and health. Fish skin, a by‐product of fish, is an excellent source of collagen. Thus, collagen was extracted from an under‐utilised species, Atlantic cod (Gadus morhua) skin, and the composite film of fish skin collagen–chitosan–cinnamon essential oil was prepared by casting. The effects of the ratio of collagen to chitosan (2:8, 4:6, 5:5, 6:4, 8:2) and the concentration of essential oil (0%, 0.1%, 0.2%, 0.3%, and 0.4% (v/v)) on the composite film were studied. The structures of the composite films were analysed using scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), and X‐ray diffractometry (XRD). The collagen content of Atlantic cod skin is approximately 50.12%, which is significantly higher than that found in basa fish and Nile tilapia (P < 0.05). The content of hydroxyproline was 4.51%. Analyses of tensile strength, elongation at break, water vapor permeability, and water solubility showed Co4Ch6 (Co:Ch = 4:6) had the optimal comprehensive performance, and Co4Ch6–0.2 (Co4Ch6 with 0.2% CEO) had high water resistance in the high‐humidity environment. As the CEO concentration rose, the composite films' infrared absorption bands were enhanced in amplitude, and the XRD peaks were gradually intensified, indicating the internal crystallinity and, thereby, the opacity of the composite films were improved. The bacteriostasis zones Co4Ch6–0.4 against Escherichia coli and Staphylococcus aureus were 2.02 cm and 1.73 cm, respectively. The DPPH radical scavenging rate of Co4Ch6 rose with the increase in CEO concentration, and the DPPH radical scavenging rate of C04Ch6–0.4 was up to 48.56%. Thus, the composite films prepared from fish skin collagen, chitosan, and cinnamon essential oils have outstanding mechanical properties, barrier ability, and antimicrobial activity and are promising for application in food packaging and storage. In addition, the composite films showed a potential antioxidation ability, which might be used as green bioactive films to preserve nutraceutical products. [ABSTRACT FROM AUTHOR]

Sodium carboxymethyl cellulose (CMC) is cross‐linked with pea protein isolate (PPI) to prepare pea protein isolate/sodium carboxymethyl cellulose (PPI/CMC) composite film by the diffusion method. The effects of the mass fraction of CMC on the mechanical properties and water resistance of PPI/CMC composite film are investigated. In the film containing 0.4% CMC, the water vapor permeability (1.43 × 10−7 g m (m2∙h∙Pa)−1) is significantly decreased, while the water contact angle value is elevated (55.76°). The tensile strength of the composite film is enhanced by 54.45%, while the elongation at break is increased by 23.30%. The film has excellent thermal stability and a homogenous structure. The remarkable changes may be attributed to new chemical interactions (hydrogen bonds) between CMC and PPI as revealed by Fourier transform infrared spectroscopy. Further, the composite film has great advantages in water resistance after comparison. The film is applied to the fresh bean skin, effectively blocking and reducing the tearing force between the fresh bean skin, and consequently easy separation after soaking in water for 20 min. Overall, the inclusion of CMC effectively solves the functional limitation caused by the hydrophilicity of PPI film, paving the way for its effective application as a novel edible packaging film in conventional foods. [ABSTRACT FROM AUTHOR]

Scale gelatin films derived from croaker fish and infused with Prosopis (Prosopis cineraria) extract (PE) at concentrations of 0.3% and 0.7% were produced. A control film, void of extract, was employed for comparative purposes. The thickness of each film was found to be statistically insignificant (p > 0.05). The results show that the highest solubility (78.57 ± 3.57%) was found for the glycerol film, and the least permeability was found for the water vapor (0.74 ± 0.09 ×10−10g s−1m−1Pa−1); however, the water vapor permeability (WVP) and water solubility (WS) of the films that contained PE were considerably lower than those of the control film (p < 0.05). In contrast to the control film, those infused with 0.7% PE exhibited exceptional UV-barrier properties (>99%) and favorable thermal characteristics. The highest and lowest antioxidant activities were found for the 7% Prosopis cineraria extract (56.96 ± 2.6%) and the glycerol film (40.66 ± 2.46%), respectively. No antibacterial activity was observed in these films. Microscopic pictures showed that all three films had a uniform and plain surface. Fourier transform infrared spectroscopy–attenuated total reflectance (FTIR–ATR) analysis revealed distinct amide bands and protein–polyphenol interactions within the films that contained the extract. [ABSTRACT FROM AUTHOR]

Edible films and coatings, composed of biological components such as proteins, lipids, and polysaccharides, play a pivotal role in various applications. While proteins from diverse plant sources, including maize, soy, and wheat, have been extensively explored for their film-forming capabilities, soybean protein remains predominant in edible films. Nonetheless, researchers have increasingly investigated alternative legume proteins, such as those derived from various beans, peanuts, and field peas, as potential candidates for edible film applications. Pea, ranked fourth globally in food legume production after soybean, peanuts, and dry beans, emerges as a promising source for edible film production. Pea protein, valued for its low cost, high protein content, and absence of genetic modifications, along with pea starch, a by-product of pea protein extraction, has become the focal point of numerous studies in edible film development. This comprehensive review focuses on the examination of pea protein isolate, pea starch, and the edible films derived from these compounds. Functional properties of both pea protein and pea starch are systematically discussed. Subsequently, we delve into the extraction methods of these components, progressing to the creation of edible films from these materials. It then delves into various characteristics of edible films produced from pea protein and pea starch, encompassing mechanical properties, water vapor permeability, transparency, and solubility. Additionally, the review explores the influence of factors such as pH, heating, plasticizers, and other treatments on these film properties. Studies highlighted in this review demonstrate that modified edible film solutions based on pea protein and pea starch exhibit considerable potential for diverse applications in both food and non-food sectors. The promising outcomes suggest that these compounds could be utilized to produce edible films tailored to specific requirements, offering new possibilities for advancements in various industries.

In general, active packaging improves the quality of ordinary packaging due to its antioxidant and antimicrobial properties which can maintain the quality of food as well as increase shelf life of safe product. In the current study, the active edible film was prepared by incorporating anise essential oil (AEO) in various concentrations (0.5%, 1%, and 1.5% v/v) into gelatin–gelatin-alginate film. The obtained results revealed that antioxidant capacity of gelatin-alginate film increased significantly (P < 0/05) following the increase in essential oil concentration due to the total phenolic content (TPC) of AEO. Elongation at break (EB), contact angle (CA), water vapor permeability (WVP), and swelling Index (SI) of the active film increased following the increase in AEO concentration, while tensile strength (TS), moisture content (MC), and solubility decreased. There was no significant difference between the color index (lightness, darkness, and yellowness) in the films containing different concentrations of AEO (P > 0.05), however, the light passing through the films decreased with the increase of AEO concentration. Continuous texture and smooth surface indicated a strong association between G-AL but multiple pores were observed across the film network with the addition of AEO. Gelatin-alginate films containing AEO showed good antimicrobial activity. Finally, according to the results of this study, it was observed that G-AL films containing AEO are suitable for food storage due to the reduction of chemical and microbial spoilage. [ABSTRACT FROM AUTHOR]

Scale gelatin films derived from croaker fish and infused with Prosopis (Prosopis cineraria) extract (PE) at concentrations of 0.3% and 0.7% were produced. A control film, void of extract, was employed for comparative purposes. The thickness of each film was found to be statistically insignificant (p > 0.05). The results show that the highest solubility (78.57 ± 3.57%) was found for the glycerol film, and the least permeability was found for the water vapor (0.74 ± 0.09 ×10−10g s−1m−1Pa−1); however, the water vapor permeability (WVP) and water solubility (WS) of the films that contained PE were considerably lower than those of the control film (p < 0.05). In contrast to the control film, those infused with 0.7% PE exhibited exceptional UV-barrier properties (>99%) and favorable thermal characteristics. The highest and lowest antioxidant activities were found for the 7% Prosopis cineraria extract (56.96 ± 2.6%) and the glycerol film (40.66 ± 2.46%), respectively. No antibacterial activity was observed in these films. Microscopic pictures showed that all three films had a uniform and plain surface. Fourier transform infrared spectroscopy–attenuated total reflectance (FTIR–ATR) analysis revealed distinct amide bands and protein–polyphenol interactions within the films that contained the extract.

The non-biodegradable synthetic plastic is one of the greatest challenges facing the food packaging business since it seriously harms the environment. To solve this problem, non-biodegradable plastic may be disposed of more affordably and with less harm on the environment by using edible starch-based biodegradable film. Therefore, the present study was focused on the development and optimization of tef starch based edible films based on mechanical properties. In this study response surface methodology was employed by considering 3–5g of tef starch, 0.3–0.5% of agar and 0.3–0.5% of glycerol. The prepared film showed the tensile strength of 17.97–24.25 Mpa, elongation break of 1.21–2.03%, elastic modulus of 17.58–108.69 MPa, puncture force of 2.55–15.02 N, puncture formation of 9.59–14.95 mm. The findings showed that as glycerol concentrations in the film-forming solution increased, the prepared tef starch edible films' tensile strength, elastic modulus, and puncture force declined while their elongation at break and puncture deformation increased. Tef starch edible films' mechanical characteristics, including as tensile strength, elastic modulus, and puncture force, were increased by the increase of agar concentration. The optimized (from 5 gm tef starch, 0.4 g agar and 0.3% glycerol) tef starch edible film exhibited higher tensile strength, elastic modulus, and puncture force while lower elongation at break and puncture deformation. The composite edible film based tef starch with agar exhibited good mechanical properties and can be suggested for application in food industry as food packaging.

Biodegradable packaging materials are increasingly being investigated due to rising concerns about food safety and environmental conservation. This study examines the incorporation of chia mucilage (CM) into starch-based films using the casting method, aiming to understand its effects on the structure and functionality of the films. CM, an anionic heteropolysaccharide, is hypothesized to enhance the mechanical and barrier properties of the films through polymer interactions and hydrogen bonding. Our findings confirm that CM incorporation results in films with uniformly smooth surfaces, indicating high compatibility and homogeneity within the starch matrix. Notably, CM improves film transparency and crystallinity. Mechanical assessments show a remarkable elevation in tensile strength, soaring from 5.21 MPa to 12.38 MPa, while elongation at break decreases from 61.73 % to 31.42 %, indicating a trade-off between strength and flexibility. Additionally, water solubility decreases from 57.97 % to 41.40 %, and water vapor permeability is reduced by 30 % with CM loading. These results highlight the role of CM in facilitating the formation of a dense, interconnected polymeric network within the starch matrix. Given the soluble dietary fiber nature of CM, the CS/CM (corn starch/chia mucilage) blended films are expected to be safe for food packaging and applicable as edible films with health benefits. [ABSTRACT FROM AUTHOR]

Edible films based on sodium alginate enriched with different percentages of Dunaliella salina powder were prepared and treated by cold plasma for diverse durations in the presence of oxygen and argon. The results demonstrated that plasma treatment, especially in the presence of argon, improves film tensile strength and Young's modulus but reduces its flexibility. Surface morphologies and topography clearly show that cold plasma's physical and chemical etching affected the microstructure of films and increased surface roughness and contact angle. Also, water vapor permeability decreased due to the reduced pores of the film and surface hydrophilicity after treatment. The results of total phenolic content and antioxidant activity of treated films containing D. salina were interestingly increased by both O2 and Ar plasma. The colorimetric findings indicated that plasma increased the intensity of redness in samples containing D. salina, with the color of these samples being more vivid. [ABSTRACT FROM AUTHOR]

Today, biodegradable packaging materials have received a great deal of attention due to growing concerns about non -degradable materials; Therefore, the aim of this study was to investigate the effect of betanine pigment on surfaces (0, 2/5, 5 W/V%) and CuO nanoparticles on surfaces (0, 2, 4 W/V%) in nanocomposite film based on whey protein isolated / pectin in the form of a central composite design on the mechanical properties and physicochemical properties of the film is produced. The results showed that with increasing the percentage of betanine pigment and CuO nanoparticles, the thickness and moisture of the samples increased and the solubility decreased (P<0.05). Also, by adding high levels of betanin pigment, redness (a) increased and brightness (L) and yellowing (b) of the samples decreased. Addition of nanoparticles decreased b value while it had no significant effect on a value of the samples. Also, by adding pigments and nanoparticles, tensile strength and elongation of film samples increased significantly (P <0.05). According to all the results, the use of CuO nanoparticles and betanine pigment in nanocomposite film leads to the production of a film suitable for food packaging with desirable physicochemical and mechanical properties. [ABSTRACT FROM AUTHOR]

The effect of dry material, glycerol and ratio of water to seed in Alyssum homalocarpum films on their thickness, transparency, moisture content, tensile strength, elongation and water vapor permeability was investigated using mixture response surface methods. Dry material and glycerol were important factors influencing tensile strength, elongation and water vapor permeability. Ratio of water to seed had little effect on physical and mechanical properties. The statistical methodology used determined the following optimal conditions for use in the casting process: 20% glycerol, 0.3% dry material content and Ratio of water to seed was 2.5.

In this study, alginate (AG) based edible films incorporated with Chinese hawthorn (Crataegus pinnatifida) berry extract (HBE) at the concentrations of 0, 1, 2, 3 and 4% (v/v) were developed and their physical, mechanical and antimicrobial properties were investigated. The results showed that the addition of HBE from 0 to 4% (v/v) enhanced the film thickness and water solubility, while reducing the moisture content of the films. The film containing 4% (v/v) HBE exhibited the highest water solubility (77.60%) and the lowest moisture content (14.54%). The colour profile analysis revealed that the presence of HBE increased the opacity, yellow and red intensity of the films. The incorporation of HBE produced films with reduced tensile strength (TS) and enhanced elongation at break (EB%). However, at 4% (v/v) HBE, the EB% of film decreased (from 43.57% to 27.67%) due to the high content of HBE. The inhibition zones against Escherichia coli and Staphylococcus aureus increased (p < 0.05) by increasing the HBE from 0 to 2% (v/v). No significant differences (p > 0.05) in inhibition zones were observed between films containing from 2 to 4% (v/v) HBE against both bacteria. Therefore, the AG-HBE film with 2% (v/v) HBE was considered as the optimal film due to its good TS (14.47 MPa) and EB% (41.13%), as well as its antibacterial properties. In conclusion, the alginate film incorporated with HBE has potential to be used in the active secondary food packaging application. [ABSTRACT FROM AUTHOR]

Chia seed mucilage (CSM) film incorporated with 2, 4, and 6 % (w /w) nanoemulsion of cinnamon essential oil (CSM-2, CSM-4, CSM-6) were developed, and their physicochemical, mechanical, antioxidant, and antimicrobial properties were determined. According to the results, cinnamon EO nanoemulsion (CEN) had droplet size 196.07 ± 1.39 nm with PDI 0.47 ± 0.04. Moreover, CSM film had higher water solubility (99.37 ± 0.05 %) and WVP (8.55 ± 1.10 g/kPa h m2) than reinforced CSM films with CENCEN. The lowest water solubility (98.02 ± 0.01 %) and WVP (3.75 ± 0.80 g/kPa h m2) was observed in CSM-6 film. Moreover, the addition of CEN improved the homogeneity and density of films and the smoothness of the surface, being observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The Fourier transform infrared (FTIR) spectroscopy also confirmed the incorporation of CEN within the film matrix. The CSM films' antioxidant (DPPH radical scavenging power) and antimicrobial (against Escherichia coli and Staphylococcus aureus) properties of CSM films were notably enhanced with the inclusion of CEN in a dose-dependent manner. The mechanical (tensile strength and elongation at break) of CSM films also was affected by the addition of CEN, TS decreased, and EAB increased (p < 0.05). The lowest TS (20.63 ± 1.39 MPa) and highest EAB (3.36 ± 0.61 %) was observed in CSM-4 film. However, CSM film was relatively dark with low opacity, and adding CEN slightly increased lightness (L*) and yellowness (b*) parameters. The superior antioxidant and barrier characteristics of the CSM edible film incorporated with CEN make it a potential candidate for product packaging and shelf-life extension. [ABSTRACT FROM AUTHOR]

Biological packaging material based on obtained proteins from fish waste, are biopolymers that have the capability of biodegradable film formation. Thus, purpose of this research is to study and investigate some of films’ physical features made from trout fish Myofibril protein. The film forming solution containing 1.5%, 2% and 2.5% (w/v) Myofibril protein isolate of 100ml solution and glycerol as plasticizer in three levels 25%, 50%, 75% (w/w) per dry material have been used. In order to solve existing protein in solution its pH must be reach to 3 by 1molar HCl. Films have been produced by casting method for 48 hours in 25°C. Then film’s mechanical features, water vapor penetrability, films solubility in water, transparency and color were investigated. Effect of protein concentration was significantly obvious on films mechanical features, thickness, water vapor penetrability and color. Obtained results from statistical analysis data by SPSS software showed that films with 2% (w/v) dry material along with 50% (w/w) glycerol demonstrated the best mechanical features.

The overall goal of this research was to examine the mechanical, water vapor barrier properties and opacity of films prepared using legume protein concentrates (faba bean, pea, lupin, lentil, and soy) as a function of glycerol concentration (50, 75, or 100% [wt/wt]—relative to the protein weight). Overall, tensile strength (TS) decreased with increasing glycerol concentration, whereas tensile elongation (TE) and water vapor permeability (WVP) increased with increasing glycerol concentration. Film opacity was independent of glycerol concentration. The effect of protein‐type varied considerably depending on the functional property of the film being measured; TS was greatest with faba bean and lowest with lupin, whereas TE was highest for pea, and lowest for soy. Lentil protein films had considerably higher WVP, at the 100% glycerol concentration, as compared to the other protein concentrates. Findings from this study indicate that legume protein concentrates are capable of forming biodegradable, edible films. Overall, pea protein concentrate films showed the most promise for application in terms of strength, elongation, and moisture barrier properties. [ABSTRACT FROM AUTHOR]

Biodegradable starch-pectin‑titanium oxide nanoparticles (TiO 2 - NPs) blend edible films were developed by casting filmogenic solution of sweet potato starch and lemon waste pectin incorporated with TiO 2 nanoparticles. The effect of incorporating different concentration of TiO 2 nanoparticle (0.5–4% wt) on the different properties of starch and pectin based edible film was evaluated. Surface color measurement, light transmission, scanning electron microscopy, fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis techniques were used to characterize the developed films. Increasing the level of TiO 2 -NPs led to significant decreases in the moisture content, solubility, and moisture uptake of the films. Addition of low concentration of TiO 2 - NPs into starch-pectin films significantly improved the mechanical and moisture barrier properties. SEM analysis also revealed that good particles dispersion could be obtained when nano-TiO 2 particles content was low (0.5–2% wt). The glass transition temperatures (Tg) shifted to higher temperature with increasing the TiO 2 concentrations and the thermal stability of the films was increased. The transmittance percentage was also decreased with increasing the TiO 2 concentrations which revealed that with UV prevention capacity, the developed films can be used as food grade UV screening biodegradable packaging material. [ABSTRACT FROM AUTHOR]

Effect of Rosella (Hibiscus Sabdariffa Linn) Extract and Surimi Dumbo catfish (Clarias gariepinus) addition on Starch-Based Edible Film-Glycerol Mechanical Properties has been done. The purpose of this study is to create an active environment-friendly packaging material. Surimi additions are intended to improve the mechanical properties of bioplastics and additions of Rosella extract intended as a bio-indicator of acidity. The method used was Solvent Casting. An amount of surimi and rosella extract varied to obtain the best mechanical properties. The results shows that the addition of surimi and rosella flower extract significantly effect the elongation of Edible films produced up to 27%.

A flaxseed mucilage-based edible film was developed with the addition of glycerol as a plasticizer. Various concentrations of glycerol were blended into the extracted mucilage, and the developed films were studied in terms of physical, mechanical, and morphological properties. As the glycerol concentration was increased from 1 to 5 wt%, the elongation at break of the films prominently increased, whereas the tensile strength and Young’s modulus decreased. The film failed to form at 6 wt% glycerol inclusion. The developed film was slightly reddish and yellowish in color, with enhanced transparency as the glycerol concentration in the film increased. Overall, this work demonstrated that with the addition of glycerol as a plasticizer up to 5 wt%, a flaxseed mucilage-based edible film could be developed as a sustainable alternative for food and bioproduct coating or packaging.

The effect of high pressure homogenization (HPH) on edible films obtained from mechanically deboned chicken meat proteins (MDCM-P), a by-product of poultry industry, was investigated. Film forming suspensions (FFS) were prepared at 4% protein concentration and homogenized up to 150 MPa. FFSs were characterized in terms of particle size and steady shear rheology, whereas optical, barrier, mechanical and microstructural properties of resulting films were determined. Particle size of suspensions decreased as homogenization pressure increased, and suspensions treated up to 50 MPa showed shear thinning behavior with higher yield stress, while higher HPH treatment caused Newtonian flow. Shear stress-shear rate data were fitted to Herschel-Bulkley model. HPH treatment improved film appearance, and all films displayed good barrier properties against UV light which induces lipid oxidations in foods. The decreasing particle size of HPH treated MDCM-P suspensions up to 100 MPa caused lower water vapour permeability (WVP) and higher tensile strength (TS), and these results were also confirmed by film micrographs which had homogeneous, non-porous and un-cracked surface images. However, porous cross sectional images were observed from 150 MPa HPH treated films. FTIR spectra of films showed similar backbone structure, and the secondary structure of films was analyzed from the area of the deconvoluted Amide I peak, which changed significantly. β-sheet and β-turn contents of films showed high correlation coefficients with TS and EAB values. It can be concluded from this study that HPH applications up to 100 MPa can enhance the mechanical and barrier properties of films. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Yuba is a soy protein–lipid film formed during heating of soymilk. This study described yuba as an edible film by analyzing its chemical composition, water vapor permeability (WVP), and mechanical properties. Three yuba films were prepared by using different concentrations and depths of soymilk: HS (86 g kg−1 and 2.3 cm), LS (70 g kg−1 and 2.3 cm), and LD (70 g kg−1 and 3.0 cm). RESULTS: As yuba was successively skimmed, the protein, lipid, and SH content decreased, but carbohydrate and SS content increased. Though both the initial concentration and the depth of soymilk affect the properties of the films, the depth of soymilk influences WVP and tensile strength (TS) more. The WVP of the HS and LS changed the least (13–17 g mm kPa−1 m−2 day1), while that of the LD changed the most (13–35 g mm kPa−1 m−2 day−1). There were no differences ( P > 0.05) in the TS between the HS and LS. LD had the greatest decrease of TS and the lowest TS among the groups. The earlier the yuba films were collected, the greater the elongation of the films was: 129% (HS), 113% (LS), and 155% (LD). CONCLUSION: The initial concentration and the depth of soymilk changed the chemical composition and structure of the yuba films. The LS yuba produced more uniform edible films with good mechanical properties. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Different source of casein depending on their extraction method from milk are available on the market. Sheets from 3 different types of casein (rennet casein, acid casein and sodium caseinate) were developed using a dry process: extrusion. Casein sourcing, plasticizer concentration (13.2% w/w or 24.2% w/w) and relative humidity environment were studied for each sheet through color, density and porosity, water sensitivity and mechanical properties evaluation. A wide range of properties seems to be available through casein based sheets depending on casein source, which affected greatly water solubility (caseinates are 100% water soluble compare to acid and rennet casein). Besides, acid and rennet casein have different behaviour with water and even more with higher glycerol amounts. Indeed, rennet casein sheet is less sensitive to water than acid casein sheet at low glycerol concentration (13.2% w/w) but at the opposite, at high glycerol amount in sheets, rennet casein sheet is more hydrophilic than acid casein sheets. Extrusion is an easy scale up process and it was used to produce casein based sheets with improved water vapor permeability (WVP). These findings can be used to find the suitable food packaging application for each casein based sheet with a low cost and efficient process. [ABSTRACT FROM AUTHOR]

Methyl cellulose (MC) films plasticized with malic acid (MA) and sorbitol (SOR) were prepared by casting solution and the influence of plasticizers at different concentrations (10, 20 and 30/100 g dry MC) on the mechanical and thermal properties were investigated. A decrease in tensile strength of the plasticized films was observed with increase in quantity of plasticizer. On the contrary, percentage elongation at break increased with an increase in plasticizer concentration that was more pronounced in SOR plasticized films. Films prepared with SOR exhibited higher water affinity and resulted in greater moisture absorption. Thermal stability was reduced with the addition of plasticizers and the SOR film samples were more thermally resistant as compared to MA-added films. FTIR analysis demonstrated the hydrogen bonding interactions between the functional groups of MC and plasticizers. The SEM micrographs of all the films showed a smooth and homogeneous surface morphology. The X-ray diffraction analysis suggested a semi-crystalline nature of the plasticized films. [ABSTRACT FROM AUTHOR]

In the present study, the physicochemical and mechanical properties of films made from anchovy (Engraulis encrasicholus)by-product proteins (ABPs) were characterized as a function of protein (3, 4, and 5%) and glycerol (30, 40, 50, and 60%) concentration. In particular, the thickness, color, transparency, water vapor permeability (WVP), solubility, oxygen permeability (OP), and mechanical properties of the films were measured, and generally, these properties were affected by both protein and glycerol concentration. The thickness, redness, WVP and solubility values of films increased, while their lightness and yellowness values decreased as protein concentration increased. Furthermore, lightness, yellowness, and elongation at break (EAB) values were found to increase at higher glycerol concentrations within ABP films, whereas tensile strength (TS) and elastic modulus (EM) values decreased. ABP films became more transparent with increase of glycerol concentration and decrease of protein concentration. The OP values of all films decreased depending on protein and glycerol concentration. The techniques for order performance by similarity to ideal solution (TOPSIS) method was used to determine optimum protein and glycerol concentrations. According to this method, an edible film containing 4% protein and 40% glycerol was the best film with aCvalue of 0.6665. [ABSTRACT FROM PUBLISHER]

Commercial extraction with organic solvents of valuable lipids from egg yolk produces a highly denatured protein waste that should be valorized. In this work, the delipidated protein waste remaining after ethanol extraction was used to prepare edible films. This material was also treated with transglutaminase, obtaining films that have also been characterized. When compared with gelatin and caseinate edible films, the films made with egg yolk delipidated protein showed poorer mechanical properties, but improved light barrier properties, low water solubility and a high degree of transparency. It is particularly interesting that the presence of phosvitin in the egg yolk gives the films important ferrous chelating properties. When the egg yolk delipidated protein was treated with transglutaminase, the strength of the film was improved in comparison with films made with untreated protein. Finally, addition of thymol and natamycin in the preparation of these films is shown to be an interesting alternative, providing them with antibacterial and antifungal capacities. [ABSTRACT FROM AUTHOR]

Recently, incorporation of natural filler such as chitosan into edible film to produce food packaging material is of particular interest due to the improvement in the properties of the film such as mechanical, morphological and optical properties of the edible film. In this work, tapioca starch-based edible film was prepared with different concentrations of chitosan; 0, 20, 40, 60, 80% w/w of dry starch solid weight. The effects of varying the chitosan concentration on the mechanical properties (tensile strength (TS), elongation at break (EAB), and Young modulus (YM)), morphological and optical properties (color and transparency) of the edible films were investigated. There was 492% increment in TS value of the edible films when chitosan was added up to 60% w/w (21.23 MPa) compared to neat starch film (3.58 MPa). The 60% w/w chitosan films exhibited smooth and even structure which indicated both chitosan and tapioca starch compounds were blended homogeneously. However, 60% w/w chitosan film exhibited very high YM value (2842.5 MPa) and low EAB value (2.46%) which might limit its application. Effects of chitosan concentration on optical properties could be considered negligible. The improvements in TS and morphological structure of the edible films will be beneficial for the potential application of film as food packaging material in which high TS is important to protect the structure of food and while morphological structure can be related to the aesthetical appearance of the food packaging materials. [ABSTRACT FROM AUTHOR]

Thermal, structural and physico-chemical properties of different composite edible films based on alginate and pectin with the addition of citral essential oil (citral EO) as an agent to improve barrier properties, were investigated. The obtained films were clear and transparent, with a yellow hue that increased with citral EO addition. All the films displayed good thermal stability up to 160 °C, with a slight improvement observed by increasing the amount of citral EO in the composites. Gas transmission rate (GTR) strongly depended on the polymer structure, gas type and temperature, with improvement in barrier performance for composite samples. Also, citral EO did not exert any weakening action on the tensile behavior. On the contrary, an increase of the elastic modulus and of the tensile strength was observed. Lastly, water contact angle measurements demonstrated the dependence of the film wettability on the content of citral EO.

This study aimed to explore the characteristics of novel fig pectin films. For this purpose, films of crude fig pectin (CFP) extracted from low-grade sun-dried fruits and films of crude (CSP) and purified (PSP) stalk pectins extracted from stalk waste of processed high-quality sun-dried figs were evaluated for their physicochemical properties. The properties of pristine (CFP, CSP, and PSP films) and CaCl 2 cross-linked films (CFP–Ca++, CSP-Ca++and PSP-Ca++ films) of fig pectins were also compared with films of commercial citrus (CP and CP-Ca++) and apple (AP, AP-Ca++) pectins. The cross-linking improved the mechanical strength and barrier properties of most films. CP, CP-Ca++, PSP, and PSP-Ca++ films showed greater mechanical strength and stiffness than other films. PSP-Ca++, PSP and CP-Ca++ films showed the lowest water vapor permeability (6.28, 12.85, 14.96 g.mm.m−2.day−1.kPa−1, respectively) while CSP-Ca++, CP-Ca++, CP, PSP-Ca++ films showed the lowest oxygen permeability coefficients (5403, 8265, 10776, 11124 mL.μm.m−2.24h−1.atm−1, respectively). All cross-linked fig pectin films showed 2–3 fold lower degree of swelling than CP-Ca++ film. The CFP-Ca++ film showed the highest surface hydrophobicity (contact angle = 101.8°) but the lowest water solubility (32.8%) and degree of swelling. Analysis of Pearson's correlations between pectin properties and film characteristics revealed that galacturonic acid (GA) content affects the mechanical properties, while GA content, degree of esterification (DE), and acetylation affect the moisture barrier performance; finally, GA content and DE affect the oxygen barrier performance of pectin films. Films of stalk waste pectins showed some properties beyond the limits of those obtained from commercial pectins. [Display omitted] • Pectins were extracted from low-grade fruits and stalk wastes of sun-dried figs. • Mechanical and barrier properties of fig and commercial pectins films were compared. • Cross-linking of films improved their mechanical and barrier properties. • Stalk waste pectin films showed the highest moisture and gas barrier properties. • Pectin composition was correlated with film properties for the first time. [ABSTRACT FROM AUTHOR]

This study investigates the effect of olive oil on the caseinate-based films. Edible films based on caseinate (5% (w/v)) and glycerol (30% (w/w)) by varying olive oil concentrations (0, 10, 20 and 30% (w/w), were prepared by casting method films. The impact of the incorporation of olive oil into the film matrix was studied by investigating the physical and mechanical properties of films. Scanning electron microscopy (SEM) was also used in order to analyse films microstructure. Increasing the olive oil concentrationup to30%(w/w) decreased values for thickness and solubility from 0.050mm and 92.18% to 0.042mm and 61.84% respectively and caused the films to become opaque. Also addition of olive oil to caseinate emulsion significantly improved the WVP (upto9*10- 10g/s.m.pa)of prepared films, but lowered the mechanical properties. The results indicate that the structure and properties of caseinate edible films were modified and improved by the olive oil. [ABSTRACT FROM AUTHOR]

The present work dealt with investigating physicochemical, barrier, mechanical and surface properties of sage seed gum (SSG) edible films as a function of plasticiser type (glycerol and sorbitol) and concentration (20, 40, 60, 80 & 100, w/w%). Based on the results, it was revealed that glycerol and sorbitol effectively plasticise the films of SSG while glycerol efficiency was higher than sorbitol. Although the films plasticised by glycerol were of high moisture content (27–49%), moisture uptake (110–140%) and solubility in water (∼80%), but they exhibited low permeability to water vapour, acceptable mechanical properties, surface hydrophilicity, and transparency. In contrast, the films plasticised by different concentrations of sorbitol exhibited a low moisture content (∼14%), water vapour permeability (lower than 4 × 10 −11 g/m.s.Pa), and moisture uptake (below 90%) with high surface hydrophobicity but less desirable mechanical properties. The probable mechanisms of plasticising are discussed in details regarding the observed characteristics of SSG edible films. Concluding, the films of SSG in present work showed a substantial potential to be incorporated in food packaging applications. [ABSTRACT FROM AUTHOR]

• CMC and lysozyme were successfully employed to produce novel antibacterial films. • CMC-Lys films were more water-resistant than pure CMC films. • CMC-Lys films had better mechanical properties than pure CMC films. • CMC-Lys films had antibacterial properties in application experiment. • Molecular changes between CMC and lysozyme were confirmed. Carboxymethyl cellulose (CMC) films containing lysozyme (Lys) were prepared in this study and changes in properties of the films were investigated. Enhancement in mechanical properties was observed with increased Lys, maximum (0.05 g/100 mL) reached to 39.07 MPa (TS) and 25.04 % (EAB). Meanwhile, water resistance ability improved, the minimum (0.05 g/100 mL) reached to 0.42 g·mm·(m2·h·KPa)-1, 84.62 % of pure CMC film. Thermogravimetric test showed better thermal stability of films. Scanning electron microscope illustrated that few cracks on surface of films. Fourier Transform infrared spectroscopy supported that more intermolecular hydrogen between Lys and CMC was formed with increased Lys, yet keeping increasing formed less intermolecular hydrogen. X-ray Diffraction observed the aggregated Lys by crystal structure. Antibacterial test showed an inhibitory effect on two common food-borne pathogens. Weight loss experiment indicated that films reduced the dry consumption of meat. Overall, the modification of CMC film by adding Lys was effective. [ABSTRACT FROM AUTHOR]

Abstract: Oxidized xanthan gum with different aldehyde content is successfully prepared by periodate oxidization and used as a crosslinking agent for gelatin edible films. X-ray diffraction measurements and atomic force microscopy images demonstrate that degradation is concomitant with the oxidization process, leading to the decrease in crystallinity and the structure changes. Glycerol-plasticized gelatin–xanthan gum and gelatin–oxidized xanthan gum edible films are prepared using casting techniques. The optical properties studies show that all films are very transparent and have excellent barrier properties against UV light. Introducing aldehyde groups can improve the UV barrier properties, resulting from the increased C N groups by Schiff's base formation. Properties studies show that xanthan gum can drastically reduce the total soluble matter, moisture content and water vapor permeability and greatly improve the mechanical properties and thermal stability of gelatin films. With the increase of oxidization level of oxidized xanthan gum, the enhancement of water barrier properties, mechanical properties and thermal stability of gelatin–oxidized xanthan gum films is observed, which is mainly due to the covalently linking between the two polymers. Subsequently, the excessive degradation of xanthan gum will reduce the mechanical properties and thermal stability of gelatin films. [Copyright &y& Elsevier]

Abstract: Soy protein isolate (SPI, 5.0 g/100 mL,) films embedded with nano-TiO2 (0, 0.5, 1.0, 1.5 and 2.0 g/100 mL) were prepared by solution casting and modified by ultrasonic/microwave assisted treatment (UMAT). The effects of nano-TiO2 content and UMAT time on the films' physical properties and structure were investigated. Incorporation of nano-TiO2 significantly enhanced films' mechanical properties and barrier properties, because of the intermolecular force between nano-TiO2 and SPI. UMAT time ≤20 min obviously improved films' tensile strength values (15.77 MPa, 245% higher than the control), and reduced water vapor permeability (1.8457 × 10−11 g cm−1 s−1 Pa−1, 72.11% lower than the control) and oxygen permeability values (0.8897 × 10−5 cm3 m−2 d−1 Pa−1, 57.66% lower than the control). SEM images also revealed a more compact and dense structure of films when UMAT time ≤20 min. Films' water adsorption properties were evaluated. GAB and Henderson models exhibited the best to fit experimental data, thus it was predicted that films (1.5 g nano-TiO2/100 ml) could be stable at low moisture content (0.27 kg of water/kg dry mass). [Copyright &y& Elsevier]

In this paper, we explore the glycosylation conditions (glucomannan content, reaction time, temperature and humidity) to probe the relationship between glycosylation and mechanical properties of soy protein isolate (SPI) film. The mechanical properties were characterized by studying the tensile strength (TS) and elongation at break (EB). Furthermore, degree of glycosylation, free glucomannan content, surface hydrophobicity, sulfhydryl groups content, lysine and arginine content of glycosylation soy protein with different reaction time were investigated to certify the significant effect of glycosylation on mechanical properties of soy protein film. What is more, the comparison of TS and EB, contact angle values and water vapor permeability of glycosylation SPI (GSPI), SPI and mixture of SPI and glucomannan films showed the excellence of GSPI. At the end, the analysis of scanning electron microscope was applied to reveal the effect of glycosylation on the structure of films. These results suggested that glycosylation with glucomannan is an ideal method to enhance the mechanical properties of soy protein isolate film. [ABSTRACT FROM AUTHOR]

Abstract: Chitosan films incorporated with various concentrations of gallic acid were prepared and investigated for antimicrobial, mechanical, physical and structural properties. Four bacterial strains that commonly contaminate food products were chosen as target bacteria to evaluate the antimicrobial activity of the prepared gallic acid–chitosan films. The incorporation of gallic acid significantly increased the antimicrobial activities of the films against Escherichia coli, Salmonella typhimurium, Listeria innocua and Bacillus subtilis. Chitosan films incorporated with 1.5 g/100 g gallic acid showed the strongest antimicrobial activity. It was also found that tensile strength (TS) of chitosan film was significantly increased when incorporating 0.5 g/100 g gallic acid. Inclusion of 0.5 g/100 g gallic acid also significantly decreased water vapor permeability (WVP) and oxygen permeability (OP). Microstructure of the films was investigated by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) and it was found that gallic acid was dispersed homogenously into the chitosan matrix. [Copyright &y& Elsevier]

Abstract: Quince seed mucilage (QSM) films containing oregano essential oil at 1, 1.5 and 2% v/v were prepared to examine their antibacterial, antioxidant, physical, thermal, microstructural and mechanical properties. Addition of 1% oregano essential oil did not affect the oxygen and water vapor permeability of the films. Incorporating OEO, increased total color differences (ΔE) and decreased whiteness index (WI). A decrease of elastic modulus (EM) and tensile strength (TS) accompanied with an increase in elongation at break (%EB) was observed with increasing oil concentration up to a level of 2.0% (w/w). Antimicrobial and antioxidant properties significantly increased with the incorporation of EO (p < 0.05). The antimicrobial activity of the QSM films incorporated with oregano essential oil was screened against 11 important food-related bacterial strains by agar disc-diffusion assay. Films containing 1% of OEO were not effective against Salmonella typhimurium and Pseudomonas aeruginosa but exhibited a strong inhibitory effect on the growth of Staphylococcus aureus, Escherichia coli, Shewanella putrefaciens and Yersinia enterocolitica as evidenced by minimal growth around the film cuts. Our results pointed out that the incorporation of oregano essential oil as a natural antibacterial agent has potential for using the developed film as an active packaging. [Copyright &y& Elsevier]

Thyme essential oil (TEO) and apple skin polyphenols (ASP) are natural compounds considered as generally recognized as safe by FDA, with biological effects against bacteria and fungi. This work aimed to evaluate physical and antimicrobial properties of açaí edible films formulated with TEO and ASP at 3% and 6% (w/w) individually or combined at 3% (w/w) each. Physical properties studied include mechanical resistance, water vapor permeability (WVP), color, and thermal resistance. Antimicrobial activity against Listeria monocytogenes was determined using the overlay diffusion test. Addition of ASP resulted in improved mechanical properties. TEO at 6% (w/w) resulted in increased elongation. ASP films had significant higher WVP than control film. ASP films were lighter and had more red color than other films. Incorporation of ASP resulted in improved film thermal stability, whereas TEO caused rapid thermal decomposition. Presence of clusters was observed on the surface of films. Addition of ASP resulted in a smother surface, whereas addition of TEO led to the formation of crater-like pits on the film surface. Açaí edible film incorporated with 6% (w/w) TEO presented the highest antimicrobial activity. However, both antimicrobials are necessary in the açaí films in order to obtain edible films with suitable physical-mechanical properties. The results of the present study showed that TEO and ASP can be used to prepare açaí edible films with adequate physical-mechanical properties and antimicrobial activity for food applications by direct contact. Practical Application Developed açaí edible films presented antimicrobial activity against L. monocytogenes and good physical-mechanical properties, showing the potential use of açaí edible films in food preservation. [ABSTRACT FROM AUTHOR]

Edible film with 2,3,4% gelatin extracted from skin of Brachirus orientalis and (20,30,40)% glycerol was prepared; it was easy to be removed from the melding, the film were fine texture and the transparent of the film was lowered and it has taken color of oil, it is thickness ranged 0.012 to 0.026 ml. the penetration of water vapor of film increased with increase percentage of gelatin and glycerol it rang from 2.13 to 9.12 gMm\M² .h. kpa Pascal, the percentage of water solubility was increase from 20.55% to 41.92%. the results showed increased in tensile strength of film with the increase of gelatin percentage and decrease with increase of glycerol whereas percentage elongation of films as increase with increased of gelatin and glycerol percentage form 2.45% to 22.95%. [ABSTRACT FROM AUTHOR]

In this research, edible films were produced using native wheat starch with different concentrations of glycerol (0, 20, 30, 40 and 50% of starch dry weight basis). Starch films were prepared by casting after gelatinization. The effects of glycerol on the microstructure, crystallinity, solubility in water, moisture absorption, water vapor permeability, optical and mechanical properties of the films at 25C and relative humidity range of 11-84% were investigated. The increase of glycerol content led to increase in film solubility, lightness, more compact structures and water absorption at 25C. The lowest water vapor permeabilities were found for the films with 20 and 30% glycerol. Glycerol did not change X-ray patterns of starch films; however, the degree of crystallinity reduced. In general, for all starch films stress at break and Young's modulus decreased and elongation increased when glycerol concentration and/or RH increased. Practical Application The inclusion of glycerol into starch films prepared by casting can increase film solubility, lightness, water absorption and produce more compact structures. Glycerol up to 30% reduced the water vapor permeability of starch films and more glycerol increased this parameter. Glycerol decreased stress at break and Young's modulus of starch films; however, elongation increased. Glycerol is able to improve some mechanical properties of the starch films. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to develop and characterise edible films produced from hydrolysed collagen and cocoa butter and plasticised with sucrose. The mechanical properties, water vapour permeability, opacity and morphology of the films were characterised. The film composition that yielded the best results was used to produce a coating for application in chocolate panned products. A water-based coating with desirable barrier properties that could replace shellac is important for the environment as well as health, and also because chocolate products have great appeal among children. The films obtained were easily manageable and flexible. Sucrose reduced tensile strength (TS), while hydrolysed collagen at concentrations above 15% increased it. Cocoa butter resulted in less-resistant films. The elongation at break values (EAB%) were higher for films containing higher sucrose concentrations. The water vapour permeability (WVP) ranged from 0.32 to 0.63 g mm m−2 h−1 kPa−1. For the same concentration of cocoa butter, the WVP was directly affected by the thickness of the film, i.e., the greater the thickness, the higher the WVP. Cocoa butter increased film opacity, while sucrose decreased it, particularly at concentrations above 17.5%. High concentrations of hydrolysed collagen produced films with more homogeneous surfaces. The brightness of the product with the coating developed in this study was attractive; however the brightness of the product with shellac was considered more intense. The properties of these films indicate that they are promising systems for coating chocolate panned products. [Copyright &y& Elsevier]

Abstract: Glycerol-plasticized gelatin edible films with a new kind of dialdehyde polysaccharide, dialdehyde carboxymethyl cellulose (DCMC) as crosslinking agent are successful prepared using casting techniques. The mechanical properties, thermal stability, light barrier properties, swelling behavior as well as water vapor permeability (WVP) of the gelatin–DCMC films are investigated. The results indicate that the addition of DCMC causes tensile strength (TS) and thermal stability to increase and elongation at break (EB) to decrease, suggesting the occurrence of crosslinking between gelatin and DCMC. The light barrier measurements present high values of transparency at 280nm and low values of transparency at 600nm of the gelatin–DCMC films, indicating that gelatin–DCMC films are very transparent (lower in transparency value) while they have excellent barrier properties against UV light. Moreover, the values of transparency at 280nm increase with the increased DCMC and glycerol content, suggesting the potential preventive effect of gelatin–DCMC films on the retardation of product oxidation induced by UV light. Furthermore, the addition of DCMC can greatly decrease the water vapor permeability (WVP) and equilibrium swelling ratio (ESR) down to values about 1.5×10−10 gm/m2 sPa and 150%, revealing the potential of DCMC in reducing the water sensitivity of gelatin-based films. In common for hygroscopic plasticizer in edible films, the addition of glycerol gives increase of EB and WVP and decrease of thermal stabilities and ESR of the gelatin–DCMC films. [Copyright &y& Elsevier]

Abstract: In this study, the physical, thermal and mechanical properties of a novel edible film based on psyllium hydrocolloid (PH) were investigated. PH films were prepared by incorporation of three levels of glycerol (15%, 25%, and 35% w/w). As glycerol concentration increased, water vapor permeability (WVP), percent of elongation (E%) and water solubility of PH films increased whilst, tensile strength (TS), surface hydrophobicity and glass transition point (T g) decreased significantly. At the level of 15% (W/W) of glycerol, PH films showed the lowest WVP values (1.16×10−10 gH2Om−2 s−1 MPa−1), E% (24.57%) and water solubility (47.69%) and the highest values for TS (14.31MPa), water contact angle (84.47°) and T g (175.2°C). By increasing glycerol concentration, PH films became slightly greenish and yellowish in color but still transparent in appearance. This study revealed that the psyllium hydrocolloid had a good potential to be used in producing edible films with interesting specifications. [Copyright &y& Elsevier]

Abstract: The properties of gellan gum edible membranes under different prepared conditions were studied in this research. Firstly, the results indicated that 0.08% gellan gum treatment can be obtained good tensile strength, moisture resistance and excellent gas-barrier edible films during the drying temperature of 60–70°C. Four typical storage conditions also were tested: refrigerated conditions (0°C), supermarket storage environment (6°C), room temperature (25°C) and high temperature (35°C). The change of gellan gum edible film properties were detected in this study for the further development of high strength gellan gum edible films. [Copyright &y& Elsevier]

Abstract: This study was conducted to evaluate the feasibility of pumpkin oil cake (PuOC) to form biodegradable films. The effect of heating treatment and pH of film solutions on films properties was determined. Film with the highest tensile strength (TS) (68.08MPa) and elongation to break (EB) (36.62%) was produced when pH was 12 and heating T 90°C. The same showed the best permeability properties. The total soluble matter and soluble protein reached the highest value, when the film was prepared at pH=12 and T =50°C. ABTS test indicated that the film produced at pH=10 and T =60°C was the best regarding the radical scavenging activity. Moisture content had not been significantly affected by the pH and heating temperature, whereas swelling capacity could be measured only for film prepared at T =80 and 90°C. To affirm and explain the influence of pH and T, scanning electron microscopy (SEM) was used. [ABSTRACT FROM AUTHOR]

The edible films based on carrot puree, carboxylmethyl cellulose (CMC), corn starch and gelatin were developed. Glycerol was added as plasticizer. Hydrocolloids and plasticizer content effects on film properties were investigated. CMC and gelatin contents did not significantly affect film %elongation (%E), oxygen permeability (OP) and water vapor permeability (WVP) but significantly enhanced film tensile strength (TS). Corn starch content significantly enhanced film TS and WVP but not significantly affected film %E and OP. Increasing glycerol content decreased film IS and increased film %E (p <0.05), OP and V/VP. Moreover, the L, a and b values of carrot films increased with the increase of the glycerol and decreased with the increase of the corn starch. [ABSTRACT FROM AUTHOR]