TEMPORAL PATTERNS OF NASAL, ORAL, AND RETRONASAL PERCEPTION OF CITRALAND VANILLIN AND INTERACTION OF THESE ODORANTS WITH SELECTED TASTANTS

Perceived intensities of aqueous solutions of 0.01% citral (C) and of 0.14% vanillin were estimated over time when presented nasally (sniffi ng), retronasally (sipping) and orally (sipping with nose pinched). Th e onset and decay of nasal perception was very rapid, with maximum int ensity reached between 4-8 s and extinction between 9-15 s. The oral r esponse was extremely low, while retronasal intensity reached maximum 11-19 s after stimulation with a duration ranging from 40 to 120 s. Or ally, 10 of 19 subjects rated solutions containing C and citric acid ( CA) significantly higher than those containing CA alone. Retronasally, citral intensity was enhanced by CA > CA + sucrose (SUC) > SUC > NaCl . Addition of xanthan gum had little effect on perception of citral. R etronasal intensity of vanillin solutions was increased by addition of sucrose (SUC) and depressed by CA and by NaCl. The results demonstrat ed large differences in perceived intensity and duration via the three procedures, significant alteration of oral intensity by added tastant s, and marked bimodality of response upon the addition of acid to citr al.