Rapid Discrimination of Different Years of Brewing Liquor by Gas Chromatography-Ion Mobility Spectroscopy Combined with Chemometrics Method

Objective: In this work, a method based on gas chromatography-ion mobility spectroscopy (GC-IMS) combined with chemometrics was established and applied to the rapid discrimination of the years of sauce-flavored liquor. Methods: GC-IMS was employed to the rapid analysis of the volatile organic compounds (VOC_S) from liquor samples. Gallery-plot, also called fingerprints, was constructed and characterized the difference of the VOC_S for different years samples via the colored spots, and applied to the discrimination of liquor years combined with PCA-CA analysis. Results: A total of 53 volatiles including monomers and dimers were identified via the NIST 2014 database of gas retention index and the database of IMS migration time for accurate two-dimensional characterization. The comparison results of VOC_S fingerprints showed that the types and contents of the compounds contained in different samples were quite different, the PCA results indicated that the samples of different years could be differentiated correctly, the PCA-CA processing results further clarified the differences and the accuracy of distinguishing results. Conclusion: This method was intuitive, fast and accurate, and would provide the method and technical support for the distinction of brewing liquor.