Influence of the incorporation form of waste from the production of orange juice in the properties of cassava starch-based films

Abstract

In the processing of orange juice, a large amount of wastes is generated, most of which are considered useless. Peels and bagasse are the main orange residues containing active and functional compounds that can be incorporated into starch-based formulations in order to allow the development of new materials with more sustainable characteristics. In this work, the cassava starch-based films were produced by casting technique. The oranges residue was added in two different forms: powder (after drying and grinding of the orange waste) or aqueous extract (by soaking the powder in water followed by filtration). To evaluate the influence of the incorporation form, viscosity measurements were carried out in filmogenic suspensions. Also, the starch-based films were evaluated by visual aspect, optical microstructure, opacity, physicochemical and mechanical properties, compounds migration in simulant solutions, antimicrobial activity, and biodegradation capacity. The addition of the orange residue significantly reduced the viscosity of the suspensions, mainly when the aqueous extract was used. The incorporation of the orange residue promoted a slight yellow color to the films, and the active films have more opacity than the starch control samples. A more heterogeneous microstructure was observed with the addition of the residue in powder form. A significant absorbance increase at 200–400 nm wavelength region permitted to prove the migration of compounds to simulant solutions of aqueous and fatty foods, showing potential for active packaging development.