Adulteration detection of essence in sesame oil based on headspace gas chromatography-ion mobility spectrometry. (15th February 2022) - Dou, Xinjing
Highlights: A simple and rapid HS-GC-IMS was developed for adulteration of sesame oil. Discriminant model of adulteration detection was built by PCA, OPLS-DA and RF. Pyrazines and 2-furfurylthiol, etc. were taken as markers of sesame essence. HS-GC-IMS possesses higher accuracy in detection of the counterfeit sesame oils. Abstract: Sesame oil is a traditional and delicious edible oil in China and Southeast Asia with a high price. However, sesame oil essence was often illegally added to cheaper edible oils to counterfeit sesame oil. In this study, a rapid and accurate headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) method was proposed to detect the counterfeit sesame oil where the other cheap oils were adulterated with essence. Combined with chemometric methods including principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS-DA) and random forest (RF), authentic and counterfeit sesame oils adulterated with sesame essence (0.5%, w/w) were easily separated into two groups. More importantly, 2-methylbutanoic acid, 2-furfurylthiol, methylpyrazine, methional, and 2, 5-dimethylpyrazine were found to be markers of sesame essence, which were used to directly identify the sesame essence. The determination of volatile compounds based on HS-GC-IMS was proven to be an effective method for adulteration detection of essence in sesame oil.