Water barrier properties of starch films reinforced with cellulose nanocrystals obtained from sugarcane bagasse

Water transport in edible films based on hydrophilic materials such as starch, is a complex phenomenon due to the strong interaction of sorbed water molecules with the polymeric structure. Cellulose nanocrystals (CNC) were obtained from sugarcane bagasse. Starch and starch/CNC films were formulated and their water barrier properties were studied. The measured film solubility, contact angle, and water sorption isotherm indicated that reinforced starch/CNC films have a lower affinity to water molecules than starch films. The effects that the driving force and the water activity (aw) values at each side of the film have on permeability were analyzed. Permeability, diffusivity, and solubility coefficients indicated that the permeation process depends mostly on the tortuous pathway formed by the incorporation of CNC and therefore were mainly controlled by water diffusion. The interaction between CNC and starch chain is favoured by the chemical similarities of both molecules.Fil: Slavutsky, Anibal Marcelo. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Cientifíca y Tecnológica; Argentina. Universidad Nacional de Salta. Consejo de Investigacion; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bertuzzi, Maria Alejandra. Universidad Nacional de Salta. Consejo de Investigacion; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones Para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones Para la Industria Química; Argentin