Comparison of sample presentations between descending and ascending series in olfactometry

Abstract

The influences of descending and ascending presentation on olfactometry have been examined in this study. Three standard odors for selection of panel members, isovalelic acid, skatole and methyl cyclopentenolone, have been used to estimate the difference of threshold values measured by descending and ascending presentation. The threshold values of nine assessors determined by 5-2 method show no meaningful influences of presentation sequence. Then the influence of difference in the definition of thresholds between the triangle odor bag method and the dynamic olfactometry has been examined by modifying the odor bag method. The threshold measurement results of n-butanol and offset printing smell for twelve assessors indicate that threshold determined by dynamic olfactometry tends to be lower about five in terms of odor index than that of the triangle odor bag method.