Rapid development of "electronic tongue" technology requires novel sensors with response toward various classes of taste substances. Potentiometric sensors gained wide acceptance for these purposes, however, they cannot provide for sensitivity toward numerous sugars, since typical carbohydrates are normally not ionized under measurement conditions. We report on feasibility study of an approach to potentiometric sensing of sugars using Saccharomyces cerevisiae (baker's yeast) as a sample modulator. The ability of the yeast to ferment sugars and proportionally increase sample acidity can be tracked with ordinary pH glass electrode and can be related to the amount of sugar in a quantitative way. We optimized measurement conditions with yeasts and demonstrated the applicability of this simple approach to quantitative sucrose determination in apple juices. (C) 2015 Elsevier B.V. All rights reserved.