Flavor stability of fried pepper oil was investigated during 30 days of storage. Variation trends of key volatile flavor compounds in fried pepper oil induced by ultraviolet (UV) irradiation and oxygen (O2) exposure were compared using GC-MS and chiral GC-MS analysis. Chirality analysis showed that conversion of (S)-(-)-limonene to (R)-(+)-limonene form was observed during storage. The storage conditions did not change the configuration of linalool, linalool oxide, or carvone. Quantitative analysis showed that the concentrations of linalool, limonene, 1,8-cineole, β-myrcene, and β-ocimene decreased dramatically during storage, whereas carvone, (E)-2-heptenal, and linalool oxide showed an increasing trend during storage. The loss rate of limonene and linalool exhibited the highest under combined UV and O2 condition, which played an important role for the aroma attenuation of pepper oil. This result will benefit the storage of pepper oil and based on pepper oil aromatic products.
Keywords: aroma attenuation; fried pepper oil; oxygen exposure; storage; ultraviolet (UV) irradiation.