Effect of Adsorbent and Lyophilization on the Recovery of Functional Compounds from Olive Pomace by Supercritical CO2 Extraction

Abstract

This study evaluated the recovery of valuable compounds from three-phase olive pomace (OP) using supercritical CO2 extraction (SC-CO2) focusing on the effects of lyophilization and adsorbent addition. Lyophilized olive pomace (LOP) and perlite-added olive pomace (POP) were compared in terms of extraction efficiency and extract quality. Total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (ABTS(center dot+)) were enhanced compared to those of raw pomace. The maximum TPC recovery values reached 2.49% and 2.68% for LOP and POP, respectively. Response surface methodology analysis demonstrated a significant agreement between experimental data and the proposed models for TPC and TPC recovery. Pressure was identified as a pivotal parameter in extraction, whereas temperature had no significant effect. While TPC was described by a linear model for OP, a two-factor interaction (2FI) provided a better fit for LOP. In contrast, the models failed to adequately describe antioxidant activity. Although POP exhibited slightly lower recovery than LOP, its lower cost highlights its potential for industrial applications.