Properties of film-forming emulsions and films based on corn starch/sodium alginate/gum Arabic as affected by virgin coconut oil content

The effects of virgin coconut oil (VCO) contents (10%, 30%, 50%, and 70%, based on the mass of gum Arabic) on the properties of the emulsions and the films of corn starch/sodium alginate/gum Arabic composite were investigated. Results showed that increased VCO content led to larger droplet size and weakened emulsion stability, as evidenced by the microscopic images. Regarding the film properties, the higher the VCO content, the lower the water vapor permeability (WVP), oxygen permeability, and water adsorption. The incorporation of VCO decreased the tensile strength but effectively increased the elongation at break of the films. Moreover, high linearity against VCO content was observed for WVP, water adsorption, and water contact angle. This study contributes to the understanding of modulating the properties of the emulsion and the resultant film by altering the oil content.