Integrated Analysis of Volatile Metabolites in Rose Varieties: Effects of Cultivar Differences and Drying Temperatures on Flavor Profiles.

BACKGROUND

Rose processing faces critical challenges in preserving bioactive compounds and aroma profiles during thermal treatments, particularly given the growing demand for natural ingredients in the food and cosmetic industries.

METHODS

Using widely targeted metabolomics, we first characterized volatile profiles of four major commercial cultivars (Hetian, Damask, Bulgarian, and Fenghua; = 6 replicates per cultivar), identifying terpenoids as dominant components ( < 0.05). Subsequent thermal optimization focused on Hetian rose, where WGCNA and K-means analyses revealed temperature-dependent dynamics (40-55 °C, triplicate drying trials per temperature).

RESULTS

Hetian rose exhibited significantly higher accumulation ( < 0.05) of a unique sesquiterpene marker, 4-(1,5-dimethyl-1,4-hexadienyl)-1-methyl-cyclohexene. Systematic drying optimization identified 50 °C as the thermal threshold for optimal color, bioactive retention, and sensory quality. Mechanistic analysis identified 193 temperature-responsive metabolites (VIP > 1, FC < 0.25 or >4, < 0.01), with terpenoid biosynthesis (MVA/MEP pathways) and esterification dynamics emerging as critical control points.

CONCLUSIONS

This study establishes the first cultivar-specific processing framework for roses, demonstrating that metabolic signature-guided drying improves product quality. The findings advance our understanding of thermal impacts on aroma biochemistry while providing actionable protocols for natural product industries.