ABSTRACT
The determination of odor threshold values can be performed in various matrices, including air, and serves as a parameter to compare the potencies of odorous compounds. Typically, the odor thresholds in air are determined by gas chromatography-olfactory (GC-O) and referenced to an internal standard, most often (E)-dec-2-enal. Herein, a direct gas chromatography-flame ionization detector-olfactory analysis method for the determination of odor thresholds in air is reported. As model substrates for this novel approach, naturally occurring substances (R)-1-p-menthene-8-thiol as well as (3S,3aS,6R,7aS)-3,6-dimethyl-3a,4,5,6,7,7a-hexahydro-3H-1-benzofuran-2-one were used. The latter compound was synthesized from (-)-isopulegol and exhibited an extremely low odor recognition threshold of 1.9 × 10-6 ng L-1 air, the lowest value reported for a fungal aroma compound thus far.
