Bioplastic from waste
Plant cuticles are the leaves' tough, waterproof outer layer. The material is nature's plastic film, and could be adapted to industrial usage. The EU-funded BIOPROTO (Bioplastic production from tomato peel residues) project investigated ways of artificially making the cuticle material from tomato skins. Europe produces over 11 million tonnes of tomatoes per year, of which the skins represent an under-utilised quarter. Yet tomato skins are cheap and chemically suitable for conversion to a cuticle-like substance. The project investigated tomato skin polymers, and the potential for their conversion to bio-plastics. The team pursued several avenues of investigation. The first stages involved chemical synthesis in a strong acid, polymer self-assembly in water, and several environmentally sustainable industrial processes. The group also used infra-red and Raman spectroscopy to aid the refinement of tomato peel residue. Results yielded a new set of films and coatings taken from the lipid portion of plant cuticles. The outcome also represented a potentially-scalable process for manufacture of bio-plastics intended for use in food packaging. BIOPROTO's new plastic is biodegradable, with minimal environmental impact. Additionally, the substance is cheap to produce, and offers competitive advantage to European businesses.
Keywords
Cuticles, bioplastic, BIOPROTO, tomato, polymer, film
