OBJECTIVE To investigate the volatile component composition of different processed Schizonepetae Herba(SH) and the impact of processing on these components, based on headspace-gas chromatography-mass spectrometry(HS-GC-MS) technology, integrating relative odor activity values(ROAV) and multivariate statistical analysis.

METHODS SH was processed using stir-baking to yellow and stir-baking until charred methods, resulting in 14 batches of SH, stir-fried SH(SFSH), and SH Carbonisata(SHC). Volatile component information of these samples was obtained through HS-GC-MS analysis. Chemometric methods such as principal component analysis(PCA), orthogonal partial least squares-discriminant analysis(OPLS-DA) and ROAV were employed to study the differences in volatile components among the different processed SH.

RESULTS Compared with SH, SFSH exhibited the disappearance of 10 components, an increase in the relative content of 28 components, and a decrease in the relative content of 6 components; in SHC, 17 components disappeared, the relative content of 15 components increased, and the relative content of 14 components decreased. Compared with SFSH, SHC showed the disappearance of 18 components, an increase in the relative content of 17 components, and a decrease in the relative content of 9 components. Through chemometric methods like PCA and OPLS-DA, successful differentiation was achieved among SH, SFSH, and SHC. Eight components, including menthone, 3-pentanal, carvone, pulegone, (R)-3-methylcyclohexanone, acetoin, iso-menthone, and benzaldehyde, exhibited differences in their relative content, serving as the main differentiating components among the three. Combining with ROAV, benzaldehyde, menthone, pulegone, iso-menthone, and carvone were identified as key aroma components contributing to the differences. Specifically, carvone contributed significantly to the aroma of SH, pulegone to SFSH, and benzaldehyde to SHC.

CONCLUSION HS-GC-MS combines with ROAV technology clarifies the differences in volatile components among SH, SFSH and SHC, providing a robust reference for establishing specialized quality control standards and clinical applications of SH and its processed products.