Characterization and intrinsic quality correlation of raw and vinegar-processed Curcumae Radix

Among the existing criteria, the traits of Curcumae Radix (CW) rely on traditional empirical identification, and the correlation between extrinsic traits and intrinsic components hasn't been systematically studied. In this study, a spectrophotometer, HS-GC-MS, and fast GC e-nose, combined with chemometrics were used to correlate the trait characteristics and intrinsic qualities of CW and vinegar-processed CW (VCW). The overall color of VCW was dark, red, and yellow, but the powder color was similar and difficult to distinguish with the naked eye. The exclusive discriminatory functional equations were established for the characterization between the two. 31 odor components were identified by fast GC e-nose. After vinegar preparation, 3 odor components disappeared and 8 odor components were generated. In addition, there were significant differences between the common components. 27 volatile components were identified by HS-GC-MS, 21 of which were terpenoids. Meanwhile, the difference discrimination models could be used for the rapid and accurate identification of CW and VCW. Through the comprehensive analysis of the color-odor-component, it was speculated that curzerene, germacrene D, and germacrone were potential chemical markers. The quality evaluation model based on the color-odor-composition of trait characteristics combined with internal components provided a basis for rapid identification and quality control of CW and VCW.