Pistacia khinjuk oil enhances oxidative stability of a corn-canola-sesame frying oil blend during six months of storage under repeated thermal treatment

The degradation of frying oils during thermal processing and storage poses a significant challenge to food quality. This study investigated the impact of blending frying oil with Pistacia khinjuk oil at concentrations of 5%, 10%, 15%, and 20% on oxidative stability and physicochemical properties over a six-month storage under thermal condition. The 20% P. khinjuk oil blend (TK20) exhibited superior oxidative stability, maintaining a high induction period (18.52 ± 0.01 h at month 1; 18.39 ± 0.00 h at month 6). Acid value was significantly reduced in TK20 (0.056 ± 0.001% at month 6, P < 0.05), peroxide values were lower in TK20 (5.30 ± 0.05 meq O₂/kg) compared to the control (7.6 ± 0.11 meq O₂/kg) at month 6, and the Totox values were also reduced in TK20 (16.2 ± 0.00) relative to the control(19.7 ± 0.00), indicating effective inhibition of both primary and overall oxidation. Polar compound formation was inhibited dose-dependently, with TK20 remaining below the 10% safety threshold (9.2 ± 0.00% at month 6). These findings demonstrate that P. khinjuk oil serves as an effective natural stabilizer, increasing frying oil shelf life and safety, offering a sustainable alternative to synthetic antioxidants with potential health benefits.