Innovative strategy to improve β-carotene recovery from carrot peel extracts: ultrafiltration with layer-by-layer graphene oxide membrane coating

Abstract

Reuse of carrot peels from industrial residues has great potential for a high value-added by-product, such as the recovery and concentration of β-carotene. The use of this compound in food is an alternative to synthetic antioxidants. Commercial modified polymeric membranes are an eco-friendly, more economical, and fouling-reduced way to obtain this compound compared to other methods used. Thus, the objective of the present study was to recover it from the carrot peel extract obtained and a triple extraction with 70% ethanol. Ultrafiltration of this extract was performed on layer-by-layer membrane modification with sulfonic groups, polyethylene glycol and graphene oxide functionalized with tannic acid. Quantitative analysis showed purification of 70.35% of β-carotene in the first filtration cycle. This showed antioxidant activity by FRAP (131.30 µmol TE/g sample) and Folin Ciocauteu (129.84 mg/L). Characterization and performance analyze showed that the modified membrane has antifouling action with flux recovery rate of 89.24%. Thus, the modified membrane can be considered an emerging technology since it has low energy consumption and ecological methodology for the recovery and purification of β-carotene.