PubMed1995
The whole mouth method gustatory test is a simple gustatory test. It can be applied easily, and can be used to assess overall taste which a subject is supposed to be feeling. In the present study, a new series of taste solutions for the use in the whole mouth gustatory test was prepared. In order to determine the normal range of gustation and relationships between each taste solution, gustatory threshold tests were conducted on 123 healthy volunteers (17-22 years old). The series of taste solutions represented 4 tastes, i.e., sweet, salty, sour, and bitter, and was prepared using sucrose, salt, tartaric acid and quinine, respectively. Recognition thresholds measured for each taste solution yielded normal ranges i.e., 0.0165 mol/l for the sweet solution, 0.0316 mol/l for the salty solution, 0.000734 mol/l for the sour solution, and 0.0000203 mol/l for the bitter solution which were almost the same as those published. The average thresholds obtained for all solutions were at almost always at the middle concentration level, i.e., level 6. Thus, this method can serve as a standard method of performing the whole mouth taste test. Principal component analysis of the thresholds obtained revealed that the primary component mainly demonstrated taste detection function, and that it could more or less be represented by the simple sum of each detection threshold. The analysis also showed that approximately 90% of taste threshold variation is explained by the 4 principal components. These findings provide further evidence that these four tastes comprise the basic elements of taste.