Toward sustainable packaging: Zeolite-reinforced cellulose/chitosan foams for fruit preservation

In this work, cellulose/chitosan foams reinforced with natural zeolite particles were developed as a bio-based insulation material for sustainable food packaging, aiming to contribute to post-harvest fruit preservation. The effect of different concentrations of zeolite particles (0.1-1.6% w/v) on final properties was studied. Light-weight foams were obtained with apparent density values (0.12-0.17 g/cm³) comparable to those of traditional commercial materials. The modified foams also presented excellent mechanical performance (elastic modulus: 0.90-2.55 MPa, compressive strength: 0.08-0.21 MPa, toughness: 41-102 kJ/m³) and showed a reinforcement effect of zeolite addition for concentrations above 0.6% w/v. The foams demonstrated excellent compressive load-bearing capacity according to the obtained support factor (3.0-4.0) and compressive strength values. Furthermore, the obtained materials showed a good performance in preserving blueberries under fluctuating storage temperatures, showing insulation performance comparable to a reference expanded polystyrene foam and enhanced spoilage prevention at high zeolite contents. Thus, the obtained foams could be promising alternatives for replacing petroleum-based materials in food packaging applications.