Enhanced recovery of antioxidant compounds from avocado pomace using ultrasound-assisted extraction systems

Abstract

Avocado oil production generates large amounts of residues, including peels, seeds, and exhausted pulp, which are rich sources of phenolic compounds with antioxidant activity. Ultrasound-assisted extraction (UAE) is a promising green technology for recovering bioactive compounds from agro-industrial wastes. This study compared the hydroethanolic UAE of phenolic compounds from avocado pomace using two system configurations: with and without recirculation. Ethanol concentration (0–100%) and extraction time (0–24 min for the non-recirculating system, and 0–180 min for the recirculating system) were evaluated. UAE was effective in enhancing phenolic recovery, providing higher phenolic yields in reduced processing time (1056 mg GAE/100 g after 15 min of extraction), when compared to the conventional extraction method (656 mg GAE/100 g after 180 min of extraction). For both systems, 15 min of extraction with 50% ethanol was identified as the best condition for antioxidant recovery. However, the recirculating system provided better temperature control. This configuration is also more suitable for processing larger sample volumes, showing greater potential for process scale-up.