Storage‐Induced Changes in Volatile Compounds in Argan Oils Obtained from Raw and Roasted Kernels

Abstract

AbstractVolatile compounds of argan oils obtained from raw and roasted kernels and subjected to accelerated storage test at 60 °C were profiled by means of headspace solid‐phase microextraction with gas chromatography coupled with high‐resolution time‐of‐flight mass spectrometry (HS‐SPME‐GC‐HRToFMS), followed by statistical multivariate analysis (MVA). Main volatile markers differentiating oils during storage were identified as 2‐methylbutanal, acetic acid, pentanal, hexanal, 2,5‐dimethylpyrazine, methyl pyrazine, 2,3‐butanediol, and 1‐methyl‐1H‐pyrrole. Principal component analysis (PCA) results show that MVA is suitable for differentiating between raw and roasted argan oils of various degrees of oxidation. Key odorants in both oils were determined by gas chromatography‐olfactometry (GC‐O) analysis, indicating butanal as the most prominent odorant for raw argan oil (flavor dilution [FD] = 8), whereas 3‐isopropyl‐2‐methoxypyrazine and 2‐ethyl‐3,5‐dimethylpyrazine with FD values of 1024 were the most prominent among 23 odorants in argan oil obtained from roasted kernels. Peroxide values (PV) indicate that argan oil obtained from roasted kernels is significantly less prone to oxidation than oil obtained from unroasted kernels.