Unraveling aroma attenuation mechanisms and storage-induced changes in fragrant peanut oil

• Household-style storage accelerated flavor deterioration in fragrant peanut oil compared with commercial shelf storage. • Hexanal accumulation and substantial loss of benzeneacetaldehyde (BA) were identified as the primary drivers of aroma decline. • Isotope tracing confirmed benzaldehyde as the major BA transformation product, accounting for ∼25% of BA loss. • Findings support improved shelf-life strategies, including oxygen-limiting packaging, antioxidant addition, and consumer guidance on proper storage. Fragrant peanut oil (FPO) is prized for its characteristic nutty and roasted aroma, yet its flavor quality diminishes during storage due to changes in key aroma-active compounds. This study systematically compared the effects of commercial shelf storage (SE1) and simulated household storage (SE2) on the evolution of FPO flavor over 112 days. Gas chromatography–mass spectrometry (GC-MS) revealed that SE2 markedly accelerated flavor deterioration, whereas SE1 more effectively preserved sensory attributes. Flavor decline was primarily driven by the accumulation of lipid oxidation products, particularly hexanal, along with a decrease in benzeneacetaldehyde (BA) levels. The BA-d5 isotope experiment verified that BA loss was attributed to two main factors: volatilization, accounting for approximately 75 %, and chemical transformation, contributing around 25 %. Isotopic tracing further demonstrated benzaldehyde as the major transformation product of BA. Spiking experiments confirmed that BA contributes positively to sweet and roasted notes, while elevated hexanal levels intensify undesirable off-flavors. These findings elucidate the mechanisms underlying aroma attenuation in FPO and offer practical guidance for shelf-life extension through oxygen-limiting packaging, antioxidant incorporation, and improved consumer storage practices.