Taste Sensor: Electronic Tongue with Global Selectivity

This chapter reviews the state-of-the-art technology of electronic tongues, mainly by focusing on a taste sensor, that is, an electronic tongue with global selectivity. It first explains the physiological knowledge of taste. The features of electronic tongues based on sensor arrays to measure liquid are low selectivity and high cross-selectivity instead of high selectivity and the capability of statistically analyzing the outputs from multiple sensors. There are two types of commercialized electronic tongue in the world. One is the taste sensing systems SA402B and TS-5000Z, which is usually called the taste sensor, and another is the Astree II e-tongue. In the future, an integrated biosensor system for the five senses will be developed to enable us to quantify the quality (palatability and safety), construct a quality information database, develop a quality description tool of foods, and visualize the five senses.