Mechanical, Antimicrobial and Morphological Properties of Biodegradable Trays Based on Cassava Starch and Agroindustrial Processing Residues

Abstract

This study investigated the development of biodegradable composites using agroindustrial residues, such as potato peels and mango integument, processed into flours (PPF and MIF), and determined their nutritional composition, total phenolic content and total tannins. The soluble and insoluble lignin content was quantified in the MIF, which exhibited a high crude fibre content (76.55%) and insoluble lignin (20.86%). Scanning electron microscopy (SEM) examined the morphology of particles and final composites, while the antimicrobial activity of MIF and potato peel extract (PPE) was tested against Staphylococcus aureus. The biodegradability of the composites was assessed in soil, comparing them to commercial EPS. In a factorial design (23), the influence of PPE (1.84–3.68 g), MIF (10–20 g) and drying temperature (55°C–65°C) was investigated regarding the mechanical strength, elongation, antimicrobial activity and physical properties of the composites. Optimal conditions for producing composites with higher strength (1.304 MPa), elongation (0.951%) and antimicrobial activity (30.036‐mm halos) included 3.68 g of PPE, 10 g of MIF and drying at 65°C. However, the interaction between MIF and temperature negatively impacted the results. Biodegradability showed a steady mass loss after 60 days. It is concluded that the use of PPE and MIF offers a sustainable alternative to conventional petroleum‐based packaging, with appropriate production conditions essential to optimize composite properties, reinforcing the potential of the food industry to adopt environmentally friendly materials.