Introduction: Pomegranate seed oil is a rich source of unsaturated fatty acids (including punicic and oleic acids) and phenolic compounds, but its high unsaturation makes it prone to oxidative degradation. With increasing use of this oil in food and health-related industries, enhancing its stability is important.

Materials and Methods: This study evaluated the oxidative stability of pomegranate seed oil from the Naderi cultivar using polyphenolic compounds extracted from pomegranate juice. The oil was obtained by cold pressing. Treatments with 0, 50, 100, and 200 µg of polyphenols per gram of oil were compared with synthetic antioxidants BHT and TBHQ. Samples were stored at 25°C for 45 days, and physicochemical properties and antioxidant activity were measured.

Results: Cold pressing yielded 15.77% oil. Punicic acid comprised 29.3% of total fatty acids. No significant changes occurred in iodine value, saponification number, or viscosity (p > 0.05), but peroxide and acid values increased over time (p ≤ 0.05). The 200 µg/g polyphenol treatment showed antioxidant activity similar to BHT and TBHQ and achieved the highest sensory scores.

Conclusion: Polyphenolic extract from pomegranate juice is an effective natural antioxidant that improves the oxidative stability and sensory quality of pomegranate seed oil. The 200 µg/g dosage is recommended for use in the food industry