Researchers from the City University of Hong Kong have developed a groundbreaking handheld interface that simulates taste sensations in virtual environments. Shaped like a lollipop, this device recreates multiple flavors using iontophoresis, a method where ions flow through biologically safe hydrogels to deliver precise flavor feedback. This innovation overcomes the limitations of earlier methods such as chemical application, thermal variation, and electrical stimulation.
The lollipop device incorporates nine taste channels filled with flavored hydrogels made from agarose mixed with water and specific flavor essences, including sugar, salt, and green tea. A compact design with ultra-thin circuit boards and a 3D-printed casing ensures portability, with the entire device weighing just 15 grams. Taste is generated by an electric current flowing through the hydrogels, which users experience by licking the device. Adding specific odor chemicals further enhances the perception of flavors.
Potential applications include standardized taste tests for diagnosing gustatory disorders, immersive online shopping where users can “taste” virtual food items, and educational environments to explore food flavors interactively. Future research aims to extend the usability time beyond the current one-hour limitation caused by hydrogel depletion.