Objective Human Gustatory Sensitivity Assessment Through a Portable Electronic Device

Objective assessment of taste perception is a challenging problem. In general, psychophysical tests based on the administration of a prototypical bitter compound, 6-n-propyltiouracil (PROP), and on a subjective scoring, are exploited. Since the PROP tasting ability is correlated to food preference and also to several clinical and health-related conditions, the development of low-cost hardware/software tools for accurate testing (e.g., in pharmacies) is an important goal. Previous works revealed the possibility to perform an electrophysiological measurement on the tongue able to provide objectiveness and repeatability in this kind of study. The technique, called Electrotastegram (ETG), relies on a custom thin-film electrode and an off-the-shelf electrophysiological recording system. In this work, we present a prototypical low-cost pocket-sized wireless device for ETG, comparing the signal quality against a top-class electrophysiological recording system already used for the same measurements. A custom Matlab interface was developed to collect and process the signal. By acquiring the signals at the same time with both devices, it was possible to compare the quality in terms of noise, amplitude and waveform. The results reveal a substantial equivalence between the two devices, thus opening to the possibility of using the proposed system in real scenarios, possibly substituting the Matlab interface with a stand-alone software.