Electrical Taste

Abstract

In 1754, a quarter of a century before Galvani’s experiments with frogs’ legs, Sulzer had described the way in which taste was induced by two different, interconnected metals touched by the tongue (lead-silver). As each of these metals by itself is tasteless, Sulzer assumed that when in contact, in one of them or in both, there occurred a vibration of the most minute particles, affecting the tongue nerves. He described the taste produced as being like that of ferro-sulphate. The same phenomenon was rediscovered by Volta (1792) who ascribed it to electric fluid flowing through the tissue from one metal to another and affecting on its way taste nerves. In his numerous experiments carried out in the “bipolar” and later “unipolar” situations, Volta found that taste depended upon the kind of metal touching the tongue. If the positive pole was at the tip of the tongue, the taste was definitely sour, and when the negative pole was in that place, the taste was “…no longer sour but more alkaline, sharp, nearing bitter.” In addition to various tastes observed at the positive and negative pole, Volta remarked that the taste lasted throughout the whole time of the current flow; that in the course of that period taste intensity went up, and that at the negative pole the weak indistinct taste was associated with the sensation of tingling and burning.