Stabilization of sesame oil during storage: mechanisms of endogenous phenolics in modulating oxidation kinetics and volatile retention

BACKGROUND: Sesame oil is a high-value edible oil with unique flavor and nutritional properties, but oxidative deterioration during storage compromises its quality and flavor stability. Endogenous phenolic compounds, particularly lignans, exhibit antioxidant activity and may regulate oxidation processes and volatile compound preservation. This study investigated the effects of endogenous phenolics on oxidative kinetics and flavor stability of sesame oil during storage. Phenolic enrichment significantly (P < 0.05) delayed increases in acid value, peroxide value and carbonyl compounds, at the same time as mitigating the decline of cis-CC bonds. Moreover, phenolics enhanced the retention of desirable heterocyclic aroma compounds, reducing pyrazine loss from 33.39% in SEO to 22.02% in SEO++P. Meanwhile, the formation of undesirable aldehydes decreased from 48.29% to 26.34%. Correlation analysis revealed positive associations between lignans and heterocyclic compounds (r = 0.597-0.773), but negative correlations with carbonyl compounds (r = -0.538 to -0.790). Volatile retention was also affected by compound hydrophobicity and volatility. CONCLUSION: Endogenous phenolics improve sesame oil storage stability by providing antioxidant protection and selectively preserving key aroma compounds. These findings highlight the important role of phenolic compounds in maintaining sesame oil quality and flavor during storage.