Influence of cellulose nanocrystal formulations on the properties of pregelatinized cornstarch and cornmint essential oil films

More people are switching to biodegradable packaging, which is better for the environment and safer for food products. Meanwhile, edible films and coatings might be an option, they are easily degradable, safe for consumption, and environmentally friendly. This study aimed to evaluate the influence of various CNC formulations as Pickering emulsions with pregelatinized cornstarch incorporating essential oil of cornmint on the characterization of edible coating solutions and film. The development of edible films was using pregelatinized cornstarch (PCS), including cornmint essential oil (CEO) and cellulose nanocrystals (CNC). To examine the impact of the CNC content on the physicochemical, mechanical, and optical characteristics of these films, different concentrations (0.05, 0.07, 0.10, 0.25, 0.30, and 0.50% w/w) of CNC were added. The coating solution's pH and viscosity, as well as the thickness and roughness of the film, usually rise with an increase in CNC concentration. Conversely, this led to a reduction in the weight loss during heating, elongation, and tensile strength, as well as Young's modulus. The different amount of CNC (%) did not have a significant effect on the water solubility, hydrophobicity, color, water vapor permeability, or surface microstructure, as observed by atomic force microscopy. The addition of CNC to the film matrix reduced its mechanical strength but basically has low water vapor permeability and high surface hydrophobicity. Consequently, the films produced in this study can be effectively used as edible films in situations that demand strong resistance to water but do not require significant mechanical strength.