Bitterness of KCl and benzoate: related to genetic status for sensitivity to PTC/PROP

Abstract

Individuals are classified as tasters or non-tasters based on their ability to detect the bitterness of PTC/PROP (Phenylthiourea/6-n-propylthiouracil). Sodium benzoate (a food preservative), potassium benzoate taste more bitter to tasters of PTC/PROP than to non-tasters. The tastes of these salts confirm the roles of ions assigned by Beidler [J. Neurrophysiol., 16, 595–607 (1953)]. The sodium cation tastes salty. The potassium cation tastes salty and bitter. At low concentrations the benzoate anion inhibits the salty taste of the sodium and potassium cations and the bitter taste of the potassium cation, but at higher concentractions the benzoate anion taste bitter and that bitterness adds to the bitterness of potassium.