Analysis of volatile compounds emitted from white champaca flowers (Michelia alba D.C.) via HS-GC-MS and SPME-GC-MS technology

The utilization of white champaca ( Michelia alba D. C.) is largely dictated by the physical state of its flowers (fresh or dried), which significantly impacts aroma characteristics and application scope. However, a comprehensive comparison of the aroma profiles between fresh and dried white champaca flowers remains scarce. This study aims to bridge this gap by comprehensively analyzing the volatile profiles of fresh and dried flowers using solid-phase microextraction (SPME) and headspace (HS) extraction coupled with gas chromatography–mass spectrometry (GC-MS) analysis, principal component analysis (PCA), and relative odor activity value (rOAV) determination. A total of 207 volatiles were identified, with the HS method extracting the highest number of compounds (150) from dried flowers, followed by SPME of dried (83) and fresh (78) flowers. Alkene and alcohol compounds dominated dried flowers, whereas esters and heterocyclic compounds were prevalent in fresh flowers. Significant differences on aroma characteristics were observed among the three flower samples, which were well distinguished by PCA. Furthermore, 15 volatiles (rOAV > 1) had a positive contribution for the overall aroma of flower samples, of which methyl anthranilate with an rOAV value of 100 was the primary contributor to the fruity note in fresh and SPME-dried samples, while linalool (rOAV = 100) imparted the dominant floral scent in the HS-dried samples. These findings provide a theoretical basis for the targeted utilization of white champaca in the fragrance and flavor industries.