Volatile compound fingerprinting for traditional sesame oil authentication using GC-MS with GC×GC-MS-assisted identification

Sesame oil (SO) is relatively expensive because of its distinctive flavor and nutritional value, which has led to adulteration such as blending with cheaper edible oils or adding SO essence. However, few studies have assessed the performance of GC-MS-based fingerprinting in the concurrent detection of SO dilution and essence adulteration from volatile profiles. Here, a detection method based on headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography-mass spectrometry (HS-SPME-GC×GC-MS) was developed to establish volatile compound fingerprints for detecting traditional SO adulteration (SO/maize oil and SO essence/maize oil). The method facilitated the identification of volatile compounds, and fingerprint similarity analysis was performed using conventional GC-MS data. It was capable of detecting maize oil dilution adulteration as low as 5% and sesame oil essence adulteration as low as 0.2%. The adulterated samples had similarity values of 0.557–0.877 and 0.482–0.579, respectively. Sensory evaluation and principal component analysis confirmed that the predicted variations were consistent with the actual adulteration levels. These findings demonstrate that the GC×GC-MS-based fingerprinting method reliably and effectively detects adulterated SO. This study provides an easily reproducible and empirically proven method for authenticating traditional SO.