Biodegradable Pectin/Starch-Based Films Applied on Fresh Pears

Packaging composed of polysaccharides has emerged as an alternative to petroleum-based commercial products. Thus, this research aimed to develop, optimize, characterize, and apply biodegradable pectin/starch-based films for fresh pears. All film-forming formulations were characterized. Digital images and optical properties suggest stable, transparent, and efficient ultraviolet (UV) blocking films, especially UVC-UVB and partially UVA. Thermal analysis indicated significant mass loss at high temperatures (above 250 °C). The films were permeable to water vapor (0.305-0.255 g × mm/h × m² × kPa) and impermeable to oil. Scanning electron microscopy revealed surface and cross-sectional changes in the material that influenced its mechanical properties, including tensile strength (0.029-0.041 MPa), Young's modulus (1.42-2.21 MPa), and elongation at break (1.69-2.98%). The films showed a water solubility of around 74% (w/w) with a maximum swelling of 233%. In addition, statistical tools facilitated optimization and data interpretation. The Simplex lattice mixture design indicated that the film containing 100% pectin (Pec-100) was more resistant and less permeable to water vapor, while principal component analysis attributed high transparency and rigidity. In this sense, the Pec-100 material showed potential for film application on fresh pears. Digital images recorded during storage suggested that coated fruits appeared fresh after 15 days. On the other hand, uncoated pears displayed degradation points starting from the tenth day. Therefore, the renewable-source-based film demonstrated promising fruit preservation results.