Development of GC-olfactometry by retronasal presentation

Abstract

Some studies have reported the differences of odor quality/intensity for the same odorant between orthonasal and retronasal olfaction. These differences could be caused by moisture in the oral cavity and partition of odorants to saliva and oral epithelium. We have to be aware of these differences to understand the effect of each component to overall flavor perception. In flavor research, gas chromatography-olfactometry (GC-O) techniques are frequently employed, as a valuable technique for detecting odorants in a sample matrix. However, all studies have been performed by only orthonasal olfaction, which detects odorants by "sniffing". We tried to apply retronasal olfaction to GC-O technique and compared the differences in odor perception with orthonasal olfaction. Therefore, we "puffed" the odorants eluted from the GC into the mouth to make retronasal responses. As results, aromagram by retronasal olfaction generally showed lower sensitivity than by orthonasal olfaction. Furthermore, odor quality of some components was different between retronasal and orthonasal olfaction.