Different Brands of Strong-Flavor Baijiu Identified Using Gas Chromatography-Mass Spectrometry and Near-Infrared Spectroscopy

Chinese strong-flavor baijiu brands are categorized into Sichuan, Jianghuai, and Beifang styles based on their regional origins. However, no systematic method exists to identify the different styles. Here, we identified different substances based on trace components and determined the similarities and differences among the different styles. We used multi-solvent liquid–liquid extraction combined with gas chromatography-mass spectrometry to detect trace components in strong-flavor baijiu. Near-infrared spectroscopy combined with three algorithms (extreme learning machine, partial least squares-discriminant analysis, and support vector machine) was used to classify the three styles of strong-flavor baijiu. Twenty-eight substances that may contribute to the individuality and generality of the three baijiu styles were identified. The prediction accuracy of the three models was more than 80%. Near-infrared spectroscopy data combined with chemometrics has great application value for rapidly identifying different baijiu brands. This method also shows potential for use in the authentication of different baijiu styles.