Abstract
Recent studies have focused on the development of food packaging films based on biopolymers, with polysaccharides being at the forefront due to their abundant availability in food and agricultural by-products. Therefore, it was the aim of this work to prepare and characterize conjugated biopolymeric films using starch, galactomannans and buriti oil (BO), with the latter acting as a partial or integral replacement for glycerol as a plasticizer. The addition of BO to either the starch or the conjugated starch-galactomannan film formulations led to distinct interactions between the components and consequently to films with distinct properties. The addition of both BO and galactomannan to starch hindered retrogradation, characterized by a diminished degree of crystallinity in comparison to the film containing only starch, attesting the stabilization of the starch molecular structures in its interaction with galactomannan molecules and with the emulsified BO. The analyses of films' mechanical properties demonstrated that the added BO did not act as a plasticizer, leading to increased tensile strength and elastic modulus and decreased elongation at break in all formulations. Overall, the films containing starch presented lower mechanical resistance than the ones based on galactomannan. All formulations led to biodegradable films, with those with BO taking longer to degrade.