White leaf mountain mint, Pycnanthemum albescens Torrey & A. Gray, also known as white mountain mint or white leaved mountain mint, is a species endemic in the American Southeast. In the present study, 24 odorants were identified using solvent-assisted flavor evaporation, aroma extract dilution analysis, and gas chromatography-mass spectrometry. Nine odorants with flavor dilution factors ≥16 were quantitated by stable isotope dilution assays, and odor activity values (OAVs) were calculated. In addition, the enantiomeric proportions of several chiral odorants were determined by chiral chromatography. Odorants with OAV ≥1 included 1,8-cineole (eucalyptus; OAV 9200), myrcene (terpeny; OAV 1400), linalool (floral, citrus; OAV 370), β-ionone (floral, violet; OAV 64), borneol (earthy; OAV 55), bornyl acetate (earthy, fruity; OAV 19), and eugenol (clove; OAV 3.1). Odor simulation experiments revealed that a mixture of the odorants with OAV ≥1 successfully mimicked the odor of an aqueous extract of the plant when combined in their natural concentrations. This study lays the groundwork for future studies aimed at determining the natural aroma variation within different populations of P. albescens and aids in the future development of selections and hybrids with targeted aroma profiles of commercial interest.
Keywords: Pycnanthemum albescens; aroma extract dilution analysis; stable isotope dilution assay; white leaf mountain mint.