Production de Bioplastique

Abstract

Global fossil plastic production raises major environmental concerns and drives the development of bioplastics from renewable resources and agro-food waste1. This study targets extracting starch from unsold white bread waste and household potato peels, then formulating bioplastic films optimized for flexibility, mechanical strength, and biodegradability. Two extraction protocols were compared: • Dry bread: simple sieving-decantation. • Potato peels: grinding-decantation with alkaline adjustment1. Extracted starches (~13% yield) underwent five sequential formulations (series A–E) incorporating glycerol, NaOH, HCl, gelatin, and nanoclay1. Each formulation was cast into films, dried, then characterized thermally (water loss at 45 °C), physicochemically (water absorption, solubility), and for biodegradability in home compost over 56 days. • Yields and purity: ~65 g starch per 500 g bread (≈85% purity) and ~106 g per 782 g potato flesh (≈92% purity). • Optimal formulation: film E3 (0.7 g nanoclay) showed +35% tensile strength, +45% Young’s modulus, and 35% reduction in water vapor permeability versus reference film. • Thermal stability: film C3 (3 mL HCl) had the lowest mass loss (0.8%) after 10 min at 45 °C1. • Biodegradability: progressive mass loss of nearly 40% by day 56 in home compost, confirming film degradability. Bread and potato waste are viable, cost-effective starch sources for high-performance bioplastics1. Alkaline and acid modifications combined with nanostructured fillers achieve an optimal balance of flexibility, mechanical strength, and moisture barrier. Notable home compost biodegradability highlights environmental benefits. The study outlines an effective valorization pathway for agro-food waste into starch-based bioplastic films1. Developed extraction and formulation protocols yield films with enhanced mechanical and 107 barrier properties while retaining significant biodegradability. Industrial-scale integration into domestic biorefineries could reduce fossil plastic reliance and food waste. Future work should optimize large-scale yields and conduct full life cycle assessments to confirm environmental advantages of this circular approach.