Development of biodegradable starch-based foams incorporated with grape stalks for food packaging.

Biodegradable cassava starch-based foams incorporated with grape stalks were obtained by thermal expansion. The morphology (SEM), chemical structure (FTIR), crystallinity (XRD), and biodegradability of the foams were evaluated. An applicability test was performed in the storage of food. SEM images showed no residue agglomerations and cell structure generally observed in materials obtained by thermal expansion; FTIR analysis verified interactions of foam components. XRD analysis showed native cassava starch characteristic peaks and the loss of crystallinity after the expansion process, with the formation of an amorphous material. Foams were completely biodegraded after 7 weeks, demonstrating that, for the experimental conditions used, the interactions between the starch and the grape stalks did not generate recalcitrant compounds or structural alterations that would impair foam degradation. Furthermore, the foams added with grape stalks presented good properties in the applicability test, showing a promising application in the storage of foods with low moisture content.