A Fully Potentiometric Electronic Tongue Enabling Comprehensive Physical and Chemical Sensations

The human tongue perceives food through the synergistic sensation of both chemical (taste) and physical (temperature, texture, softness) cues. Inspired by such functionalities, electronic tongues (e-tongues) have been developed for applications ranging from food analysis to biomedical sensing. However, most reported e-tongues primarily capture chemical tastes, overlooking critical physical attributes. In addition, current e-tongues typically rely on heterogeneous sensor outputs (e.g., current, capacitance, impedance), which complicates circuit design and signal processing and leads to high system power consumption. Here, we present a fully potentiometric, monolithically integrated multimodal e-tongue capable of simultaneously sensing chemical attributes (e.g., salinity and acidity) and physical attributes (e.g., temperature, texture, softness) of food. Importantly, all integrated sensors self-generate a unified output─potential difference (mV)─thereby eliminating the need for external power. Such a fully potentiometric sensor integration also greatly simplifies the signal acquisition circuitry and drastically reduces the system power consumption. Assisted by machine learning algorithms, the proposed fully potentiometric e-tongue achieves high accuracy in discrimination of both fruits and beverages, outperforming conventional single-modality e-tongues. This work demonstrates a practical route toward holistic gustatory sensing and offers new opportunities for the development of biomimetic intelligent systems that closely replicate natural taste perception.