The Role of Temperature and Duration in Roasting Camellia Oleifera Seeds for Quality Improvement of the Oil

Roasting is a critical factor that determines the functional quality of Camellia oleifera seed oil (CSO); however, the synergistic effects of roasting temperature and duration on oxidative stability and bioactive compositions of CSO remain unexplored. Herein, Camellia seeds were roasted across temperatures ranging from 90°C to 180°C for 20–60 min to elucidate the dynamic competition mechanism that governs CSO quality. Physicochemical properties, antioxidant capacity, and minor‐component profiles of the resultant CSO were evaluated using a multi‐dimensional approach. Hierarchical cluster analysis identified that temperature was the dominant factor for quality variation. The condition of 120°C/20 min showed optimized oxidative stability, antioxidant capacity, and α‐tocopherol retention. Notably, phytosterols exhibited structural duality: sitosterol was positively correlated with oxidative stability index and FRAP reducing activity functioning as an antioxidant, whereas conjugated sterols (stigmasta‐3,5‐diene‐3‐ol, clerosterol) showed a pro‐oxidative tendency. Roasting temperatures above 150°C induced sterol isomerization and lipid oxidation. Principal component analysis confirmed 120°C/20 min as the optimal condition. This work established sterol structural duality as a predictive biomarker for CSO quality, which is quantifiable using multiple linear regression, and proposed a temperature‐duration equilibrium concept to guide industrial roasting optimization.