Chemometric Discrimination of Korean and Chinese Kimchi Using Untargeted Metabolomics

Background/Objectives: Kimchi has gained global recognition for its unique taste and health benefits, but its quality is totally different according to its geographical origin of materials and production methods. Methods: In this study, differences between Korean (53 samples) and Chinese kimchi (72 samples) were investigated through comprehensive metabolomic analysis using gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF MS). Results: Multivariate statistical analyses revealed a clear separation between the two groups. Thirty-four metabolites contributing to the separation were identified. Korean kimchi was enriched in sucrose, quinic acid, sinapic acid derivatives, rutin, capsicosin, and capsianoside, while Chinese kimchi contained higher levels of trihydroxy octadecenoic acid, 2-hydroxypalmitic acid, pinellic acid, maltose, glucuronic acid, and corchorifatty acid F. In particular, the univariate Bayesianlogistic regression analysis revealed that among these metabolites, rutin, capsicosin derivatives, and sinapic acid derivatives showed strong potential as origin-discriminant markers of kimchi, providing insights into how these metabolites influence its nutritional and sensory properties. Conclusions: These compositional differences may be attributed to variations in raw materials and production methods of kimchi.