Recycling citrus waste to develop sustainable products

Millions of metric tonnes of citrus fruit are processed globally each year to make fruit juice, but as much as half of this may go to waste. However, an evolving international collaboration between UK and Brazilian partners could support the world’s largest citrus farms to develop new products and markets from this waste.

A York University team has developed novel, patented technology, based on additive-free, low temperature microwave processing, to release the chemicals and materials from citrus residues. Through exchange visits, including visits to orange farms in Brazil, and co-organised workshops with local partners, the project has helped to bring together key actors from research and industry, with the aim of developing new facilities in Brazil to exploit this citrus waste and create new green value chains. This could have major impacts given Brazil’s substantial, largely unexploited biomass potential.

Orange waste can be used in multiple products, including food additives, solvents, flavours and fragrances. Substituting petrochemical-based products with these renewable, biodegradable and non-toxic products could benefit consumers and the environment. Locating biorefineries based on food supply chain waste closer to the raw materials would also avoid transport costs. Overall developing this new industry in Brazil could provide many opportunities, with substantial financial, social and economic benefits for the country as well as wider environmental benefits.

Steps are underway to create a new citrus waste demonstrator facility in Brazil. This technology is also being discussed with large-scale orange processors in Turkey and South Africa.

"Orange producers could create new industries, Brazil could be a demonstrator to show this work." 

James Clark, University of York