Abstract
Nodogoshi is the Japanese term for the sensation of swallowing, which can be determined by subjective assessment. In this study, we examined the effect of viscosity of liquids on Nodogoshi using sensory characteristics and electromyographic activity. The effects of participant age and head position during swallowing were also taken into consideration. We used vitamin water with viscosities of 1, 40, 60, and 90 mPa s (denoted by η1, η40, η60, and η90, respectively) at a shear rate of 50 s−1. In the sensory evaluation of Nodogoshi, the young participants found that η90 was less palatable than η40 (p<0.05) and there was no difference between the η1, η40, and η60 samples. In contrast, the elderly participants found η60 to be more palatable. Both young and elderly participants found that the η90 drink had the most unpalatable aftertaste. The results of this study suggested that Nodogoshi may be affected by the viscosity of a drink; however, it is difficult to determine the optimum viscosity that makes a drink palatable because it depends on the tastes and preferences of individual drinkers.
