Fragrance chemistry requires the separation and identification of many closely related compounds in essential oils, fragrance compositions, and aroma chemicals. Specific identifications may be used by the perfumer to determine the contribution of a component to the final product, to evaluate organoleptic and chemical compatibility within both a formulation and the consumer product to assure safety requirements, and for quality control.
The infrared spectrum of a sample is a plot of the intensity of light absorbed by that sample vs. the frequency in the mid-inflared range. The spectrum can bc considered the fingerprint of the sample, permitting comparison with a known reference spectrum for identification. Failing that (perhaps the reference is not available), infrared can still be useful in elucidating chemical functionality, differentiating isomers, and corroborating structure postulates.
Gas chromatography is the primary analytical separation technique in the perfume industry. An instrument providing the ability to measure the infrared spectra of components of a mixture, online, as the components elute from the chromatography, would certainly be a logical marriage of the two analytical disciplines.