An Electronic "Tongue" Based on Multimode Multidirectional Acoustic Plate Wave Propagation

Area of Science:

• Acoustic wave physics
• Chemical sensing
• Materials science

Background:

• Traditional taste detection methods can be complex and time-consuming.
• Developing rapid, non-destructive analytical techniques is crucial for quality control.

Purpose of the Study:

• To demonstrate the detection of five basic tastes using higher-order acoustic waves.
• To develop an acoustic electronic tongue for analyzing liquid properties.

Main Methods:

• Utilizing acoustic waves propagating in piezoelectric plates.
• Measuring changes in propagation losses (ΔS12) in response to different liquid solutions (NaCl, glucose, citric acid, MSG, sagebrush).
• Analyzing physical properties like density, viscosity, conductivity, and permittivity of liquids.

Main Results:

• Each substance generated a unique orientation histogram of acoustic responses.
• Acoustic wave attenuation was influenced by both electrical and mechanical properties of liquids.
• Different acoustic modes responded distinctively to various liquid properties.

Conclusions:

• A multi-parametric, multimode acoustic electronic tongue can differentiate liquids based on taste profiles.
• This technology offers a pathway for operational analysis of various liquid substances without extensive chemical analysis.