Valorization of food side streams by supercritical fluid extraction of compounds of interest from apple pomace

International audienceSupercritical CO2 (scCO2) extraction, a green technology still little applied to side streams, has been used to explore the potential recovery of beneficial compounds from apple pomace, a food industry byproduct. The study examines the potential of scCO2 extraction on freeze-dried and airflow dried apple pomace, using laboratory-scale equipment with varying pressures (200–400 bar), temperatures (35–55 °C) with a fixed CO2 flow rate. Extracts were analyzed through LC-MS and GC-MS, while antioxidant capacity was assessed using the ABTS assay. The results were compared to those from Soxhlet n-hexane extraction. Optimal conditions of 300 bar and 55 °C with freeze-dried apple pomace yielded the highest mass loss. The main compounds identified included glyceryl dilinoleate, linoleic acid, and diacyl glycerol, with significant ursolic acid content. A preliminary higher scale feasibility test under optimal conditions demonstrated promising, duplicable outcomes, supporting prior claim that apple pomace contains valuable ingredients that can be reused in various industrial sectors