Valorization of Eichhornia crassipes for Biodegradable Food Packaging

Abstract

Water hyacinth (Eichhornia crassipes) is an invasive aquatic plant widely distributed in freshwater bodies in Sri Lanka. Its rapid proliferation obstructs waterways and adversely affects aquatic ecosystems. This biomass is often removed during management activities, but its productive use is limited, presenting an opportunity to turn this resource into a value-added material. This study investigated the valorization of E. crassipes biomass for the development of biodegradable starch-based sheets intended for food-packaging applications. The collected biomass was subjected to sodium bicarbonate (NaHCO3)-assisted alkaline boiling, pulped, and incorporated into a cassava-starch matrix. Three water hyacinth fibre/starch formulations, 40:60 (S1), 50:50 (S2), and 60:40 (S3), were fabricated by wet forming and evaluated for tensile strength, density, water absorption, and thickness. The fibre/starch ratio considerably influenced the measured properties. S2 achieved the highest tensile strength of 63.73 MPa, whereas S1 and S3 recorded 54.80 and 58.00 MPa, respectively. S1 exhibited the lowest density (0.83 g/cm3), water absorption (141.66%), and thickness (2.0 mm), compared with 1.08 g/cm3, 170.00%, and 2.6 mm, respectively, for S3. The 40:60 fibre/starch formulation showed the best overall performance, though its high water absorption indicates a need for better moisture resistance. These findings suggest a method to transform invasive E. crassipes biomass into biodegradable packaging, connecting aquatic weed management with waste valorization material use in Sri Lanka.