Development of green banana (Musa paradisiaca) as potential food packaging films and coatings

The aim of this study was to develop biodegradable packaging films based on a unripe green banana (Musa paradisiaca L.) with different plasticizers; glycerol, polyethylene glycol (PEG) and sorbitol at various concentrations (10-50%). Banana films were produced by using casting method and physical properties of these films were determined. Banana films with 10% of PEG showed the lowest water solubility (P≤0.05) followed by films with glycerol and sorbitol. Banana films with 40% plasticizers possessed the lowest water vapour permeability (WVP) whereas films with 30% glycerol exhibited higher values of tensile strength (P≤0.05) compared to films with PEG and sorbitol. However, types of plasticizers did not influence the thickness of the films. Also, used of higher concentrations of plasticizers had increased the solubility values. These findings reveal that concentrations and types of plasticizers have significant roles to provide banana film or coating with good physical properties

Effect of different types and concentrations of emulsifier on the characteristics of kappa-carrageenan films

κ-Carrageenan films derived from Euchema cottoni containing different types and concentrations of emulsifier were developed. Film formation without the addition of emulsifier was used as a control. The physical, mechanical, optical and microstructural properties of these films were determined. Different types of emulsifiers (Tween 20, Tween 40 and Tween 80) exerted significant effects (P ≤ 0.05) on the thickness, moisture content and opacity of the films. Additionally, Tween 20 and Tween 40 with concentrations from 0.1 to 0.5% (v/v) significantly (P ≤ 0.05) improved the tensile strength of the films, ranging from 7.35 to 13.83 MPa. The water vapor permeability of the carrageenan films was significantly (P ≤ 0.05) affected by both factors. Increasing the emulsifier concentration also caused an increment in the number of lipid droplets contributing to a smooth surface. Therefore, this study suggests that different types and concentrations of emulsifiers play essential roles in determining the physical properties of carrageenan films

Storage stability of soy protein isolate films incorporated with mango kernel extract at different temperature

This research investigated the storage stability of antioxidant films made from waste and by-products which are soy protein isolate (SPI) and mango kernel extract (MKE) stored at room temperature (25 °C), refrigeration temperature (4 °C) and frozen temperature (−18 °C) for 90 days. The thickness of the films was maintained from 0.050 to 0.058 mm until the 90th day. The colour properties of SPI films incorporated with MKE (SPI + MKE) were generally not significantly affected by time and temperature except for the b value. All the films turned darker over the storage time. There was no dominant factor between temperature and time for the mechanical properties; all the films showed an increase in tensile strength and Young's modulus, and a decrease in elongation. The antioxidant activity of the films was determined by the total phenolic content and radical scavenging activity of DPPH and ABTS. SPI + MKE film at 25 °C showed the highest antioxidant activity as compared to films stored at 4 °C and −18 °C in all the analyses, with the result being significant in DPPH and ABTS analyses. The film stored at 25 °C showed 26 to 50% higher (p > 0.05) TPC than films stored at 4 °C and −18 °C, respectively and had the highest antioxidant activity (54%) in ABTS analysis (p < 0.05). SPI + MKE film stored at 25 °C also showed only 1% depreciation of radical scavenging activity (RSA) throughout the storage time. The highest decrease (4%) in antioxidant activity was recorded for SPI + MKE film stored at −18 °C, although it was considered very low. This shows that the antioxidant activity of the films is stable for 90 days of storage

Physicochemical characterization of kappa-carrageenan (Euchema cottoni) based films incorporated with various plant oils

This study investigated the effects of different types of plant oil (olive oil, corn oil, soybean oil and sunflower oil) on the physical and mechanical properties of kappa-carrageenan films from Euchema cottoni species. The incorporation of plant oils increased the film thickness significantly (P < 0.05). However, the moisture content, solubility and tensile strength of films decreased significantly (P < 0.05) as plant oils were added. The incorporation of plant oils also contributed to a plasticizing effect, whereby the values for elongation at break increased significantly (P < 0.05), from 22.3% to 108.8%. Higher oil content also led to carrageenan films with lower opacity, which contradicted with previous studies. In conclusion, the plant oils used in this research significantly improved film properties, thus demonstrating the potential of these materials to be used as food packaging films and coatings

Functional and antioxidant properties of protein-based films incorporated with mango kernel extract for active packaging

This research is focused on developing active packaging by using food industries’ by-products. Soy protein isolate (SPI) and fish gelatin (FG) were used as the sources of biopolymers and different concentrations of mango kernel extracts (MKE) from 1 to 5% were added as natural antioxidants. Thicker and more translucent films (p < 0.05) were produced when a greater concentration of MKE was incorporated in both films. The mechanical test revealed that the addition of MKE increased the tensile strength of both films (p < 0.05), with higher tensile strength recorded in FG films than in SPI films. The incorporation of MKE significantly (p < 0.05) decreased the water solubility up to 22 and 33%, in FG and SPI films, respectively. The water vapor permeability (WVP) of SPI with the incorporation of MKE improved up to 10%. In contrast, FG films incorporated with MKE showed higher WVP in comparison with the control. The antioxidant activity increased with a greater concentration of MKE incorporated in both antioxidant films (p < 0.05) with more impact in SPI films compared to FG film in DPPH, FRAP and ABTS analysis. DPPH analysis on SPI films revealed the highest antioxidant activity (89%) with the inclusion of 5% MKE extract. Though both films were found to have the potential to be developed as antioxidant films, yet the overall observations revealed that SPI outperformed FG as active packaging films

Effect of extrusion barrel temperatures on residence time and physical properties of various flour extrudates

The aim of this study was to evaluate the effect of barrel temperature and flour types on the residence time and physical properties of various flour extrudates. Corn flour, rice flour, corn flour with potato starch (30% w/w, d.b), and rice flour with potato starch (30%w/w, d.b) were extruded at screw speed of 75rpm, feed moisture at 25% (w/w, w.b.), barrel temperature ranging from 80°C to 140°C and die size of 1.88mm. The extrudates were dried at 50°C overnight and further analysed. Results showed that an increase in extruder barrel temperature decreased the residence time of the flours in the extruder (from 4.11-11.32min to 2.24-6.76min), but increased the expansion ratio, rehydration ratio, water absorption index, water solubility index and b value of the extrudate (p≤0.05). The extrudates had the mean residence time and physical properties of rice flour<rice flour with potato starch<corn flour with potato starch<corn flour (p≤0.05). Results showed conclude that barrel temperature and flour types showed significant effect on the residence time and physical properties of the extrudates

Utilization of mango peel extracts on the biodegradable films for active packaging

Mango peels extract (MPE) was incorporated into fish gelatin films to determine their physical, barrier, mechanical and antioxidant properties for active food packaging. Films with three different concentrations of MPE (1–5%) were prepared by solution casting method. Films incorporated with MPE showed a decrease (P > 0.05) of water vapor permeability (WVP) and lower (P ≤ 0.05) films solubility. High level of MPE films also exhibited more rigid and less flexible film formation. Colored tint films and a reduction in transparency were due to the hydrogen bond linkages between fish gelatin molecules and phenolic content within the film matrix. Higher free radicals scavenging activities also observed for films with higher concentrations of MPE. This study reveals the benefits of mango by-products incorporated into gelatin based films as a potential material for active packaging

Effect of aloe vera (Aloe barbadensis Miller) gel on the physical and functional properties of fish gelatin films as active packaging

Present study was conducted to investigate the feasibility of the combination of fish gelatin and Aloe gel in producing composite films and to determine the effect of Aloe gel concentrations (1, 3, 5, 7 and 9% wt/wt) on the physical properties and antioxidant activity of the composite films. The moisture content of the composite films was proportional to the concentration of Aloe gel. Also, the water solubility and tensile strength of the films decreased with increasing Aloe gel concentration. However, Aloe gel did not cause any significant effect (p ≥ 0.05) on thickness, water vapour permeability (WVP) and colour of the composite films. The gelatin/Aloe composite films exhibited smooth surface microstructures similar to non-composite gelatin film when observed under scanning electron microscope (SEM). The gelatin/Aloe composite films also showed concentration dependant ABTS and DPPH radical scavenging activities

Potential of silver-kaolin in gelatin composite films as active food packaging materials

This study discovered the potential application of kaolin (Kln) and silver-kaolin (Ag-Kln) in gelatin-composite films as active packaging material for food products. Three different types of kaolins; raw Kln, Ag-Kln (1:2) mix and Ag-Kln (1:1) mix with various concentrations (15%, 30% and 45%) were prepared by solution casting. For the water barrier properties, the wettability test indicated that the addition of kaolin in gelatin films produced hydrophobic films and lower (p < 0.05) water vapour permeability, regardless of the kaolin type and concentration. Scanning electron microscopy images portrayed that higher inclusions of Ag-Kln compounds are able to develop smoother surface and homogenous cross-section. In addition, by incorporating these two materials, films with great antimicrobial effect towards both Gram-positive and Gram-negative bacteria were produced. Elevation of Ag-Kln concentration also proved to lower the transmission of ultraviolet-vis light through the films. These findings suggested that gelatin film with Ag-Kln has a potential and beneficial in food packaging industry due to its enhanced properties. tilizer formulations for crop growth on acid soils

Fish gelatin films incorporated with different oils: effect of thickness on physical and mechanical properties

Properties of fish gelatin films incorporated with different oils at different thickness investigated. Gelatin films incorporated with all oils resulted in higher elongation at break (EAB) compared to control film, regardless of the oils type (P≤0.05). Increasing the thickness of gelatin films with oils decreased the solubility value (P≤0.05) significantly. However, water vapor permeability (WVP) of gelatin films containing oils increased as the thickness of films increased. FTIR spectra showed that incorporation of different oils into gelatin films gave effect on the molecular organization and intermolecular interaction in films matrix particularly at the wavenumber of Amide-I band and 1739-1744 cm-1. SEM analysis revealed the addition of oils into gelatin films enhanced the roughness of the film surface and cross-section. An appropriate combination of oils at moderate thickness could improve the mechanical and barrier properties of fish gelatin films thus fulfill the application either as coatings or films