Effect of fatty acid composition on rosemary antioxidants in stabilizing woody edible oils: a kinetic and machine learning analysis of volatiles under accelerated oxidation

Prioritizing woody oil-bearing crops is essential to addressing edible oil supply-demand imbalances, yet oxidation remains a key challenge. Rosemary crude extract (RCE), an approved food-grade antioxidant, requires further evaluation for stabilizing woody edible oils. This study assessed RCE and its key component, carnosic acid (CA), in Camellia, Xanthoceras, and Paeonia seed oils, categorized by predominant fatty acids (n-9, n-6, and n-3 types), comparing their effects with α-tocopherol and TBHQ. CA demonstrated broad-spectrum inhibition of volatile oxidation products across all oil types, while RCE exhibited stronger inhibition in n-6 type oils. Machine learning revealed selective antioxidant efficacy for fatty acid-specific oxidative markers. Additionally, CA effectively suppressed malondialdehyde and free fatty acid formation, with kinetic analyses confirming its superior stability, which increased with the oxidative stability of the oil. These findings highlight selective antioxidant mechanisms and support rosemary-derived antioxidants as sustainable solutions for preserving woody edible oils.