Enhancing Oxidative Stability of Palm Olein Oil Using Yemeni Red Onion Peels Extract (Allium cepa L.) During Deep-Frying

Abstract

This study evaluated the antioxidant potential of Yemeni red onion peels (YROP) extract in enhancing the oxidative stability of refined, bleached, and deodorized palm olein (RBDPO) Oil under deep-frying conditions (170–180°C for 25hours). The extract, applied at 200 and 400ppm, was compared to the synthetic antioxidant TBHQ (100ppm). At 400ppm, the extract effectively reduced free fatty acids and peroxide values by over 20%, preserved oil color, and achieved an oxidative stability index (OSI) of 15.20hours, close to TBHQ (17.53hours) and superior to untreated oil (10.25hours). Antioxidant activity (49.05% DPPH inhibition) and total phenolic content (37.36mg GAE/g DW) supported its effectiveness. These findings indicate that the YROP extract demonstrates notable antioxidant potential, enhancing oil quality and shelf life, while promoting sustainable utilization of agro-industrial waste.