Electronic Tongue (E-Tongue) is an instrument used for taste measurement and comparison. Electronic Tongue is a sensor device used for recognition (identification, classification, discrimination), quantitative multicomponent analysis and artificial assessment of taste and flavor of various liquids. Electronic tongue is an analytical instrument comprising an array of non-specific, low selective chemical sensors with partial specificity (cross-sensitivity) to different components in solution, and an appropriate method of pattern recognition and/or multivariate calibration for the data processing. Electronic Tongue instruments are designed to analyze the taste of liquid samples or solids dissolved in liquids. In a way similar to human tongue, the Electronic Tongue provides a global “taste fingerprint” of a complex mixture of organic / inorganic compounds.

Applications of Electronic Tongue Taste Analyzer

Electronic Tongue (E-Tongue) is specifically designed for taste analysis in R&D, formulation, food product development, and food process improvement applications. Electronic Tongues have several applications in various industrial areas: the pharmaceutical industry, food and beverage sector, etc. It can be used to:

  • Analyze flavor ageing in beverages (for instance fruit juice, alcoholic or non alcoholic drinks, flavored milks, etc.)
  • Quantify bitterness or “spicy level” of drinks or dissolved compounds (e.g. bitterness measurement and prediction of teas)
  • Quantify taste masking efficiency of formulations (tablets, syrups, powders, capsules, lozenges, etc.)
  • Analyze medicines stability in terms of taste
  • Benchmark target products.

Working Principle of Electronic Tongue Taste Analyzer

Electronic Tongue taste analyzers consist of three main parts: a sampling system, a detection system, and a data acquisition and processing system. Chemical compounds responsible for taste are perceived by human taste receptors, and the potentiometric chemical sensors of electronic instruments detect the same dissolved organic and inorganic compounds. Like human receptors, each sensor has a spectrum of reactions different from the other. The information given by each sensor is complementary and the combination of all sensors results generates a unique fingerprint. Most of the detection thresholds of sensors are similar or better than those of human receptors. In the biological mechanism, taste signals are transducted by nerves in the brain into electric signals. E-tongue sensors process is similar: they generate electric signals as potentiometric variations.

Taste quality perception and recognition is based on building or recognition of activated sensory nerve patterns by the brain and on the taste fingerprint of the product. This step is achieved by the e-tongue’s statistical software which interprets the sensor data into taste patterns.

Liquid samples are directly analyzed without any preparation, whereas solids require a preliminary dissolution before measurement. Reference electrode and sensors are dipped in a beaker containing a test solution for 120 seconds. A potentiometric difference between each sensor and a reference electrode is measured and recorded by the E-Tongue software. These data represent the input for mathematical treatment that will deliver results.