One of the biggest challenges for the juice industry is finding ways to reuse citrus fruit peels, which account for more than 40% of the weight of the raw material used in production. To resolve this issue, researchers from the State University of Campinas (Unicamp) developed a biotechnological method that allows recycling this waste, transforming it into a material with added economic value suitable for other purposes.
Using food engineering knowledge, the researchers adapted a pectin extraction method, which uses citric acid, to be used in orange peels, taking advantage of this type of soluble fiber present in the residue. Water-soluble pectin is widely used by the food industry in the manufacture of products such as jellies, jams and other sweets.
The team was also able to extract xylan from the remaining residue, a substance that can be converted into xylo-oligosaccharides through enzymatic processes. Xylo-oligosaccharides are carbohydrates with prebiotic characteristics that promote the feeding of health-benefiting bacteria present in animal intestinal flora.
“The present invention contributes to reducing environmental impacts related to the disposal of orange peels in the environment and the chemical waste generated by industries for the production of pectin and xylo-oligosaccharides”, Manoela Martins, a doctoral student in food engineering, tells Agência Fapesp from Unicamp, researcher who participated in the study and a Fapesp scholarship holder.
The technical procedures allowed the production of pectin with more than 80% purity, making it possible to recycle orange peels and reducing the amount of waste sent to landfills. Reusing this waste is a way to promote the circular economy and contribute to sustainability.
Martins also adds that the integrated process optimizes the use of water and solvents and reduces operating costs, which adds value to the raw material and increases profitability. “The high availability of orange waste allows the process to be operated throughout the year to meet the demands of the pectin and xylo-oligosaccharides market. The technology has the potential to be operated in an industrial plant that already processes oranges or orange waste, reducing initial installation investments,” he highlights.
The research was funded by Fapesp and coordinated by professor Rosana Goldbeck Coelho. The researchers filed a patent application for the invention at the National Institute of Industrial Property (INPI).
