A new device for evaluating the continuity of taste was developed with the use of surface plasmon resonance (SPR). The model of lingual cells was constructed with liposomes immobilized onto an L1 sensor chip for SPR. Using this device, we classified food components into three categories according to the sensorgram pattern and residual ratio on lipid bilayer. Samples in group A strongly interacted with lipid bilayer, those in group B poorly interacted, and those in group C belong to neither group A nor group B. Sweet proteins and gymnemic acids that prolonged sweet perception were categorized in group A. Almost all the carbohydrates investigated and aspartame, of which the taste perception does not continue, belonged to group B. This device made it possible to detect the interaction with lipid bilayer and dissected the mechanism of taste continuity.

We have developed a device that analyses the interaction of food components with model epithelial cells using surface plasmon resonance (SPR). A model of epithelial lingual cells was devised using a liposome composed of a mixture of four phospholipids. The liposome was immobilised to the L1 sensor tip attached to the sensor port of the SPR system. The interaction of food components with the model lingual epithelial cells was determined by the patterns of sensorgrams. According to this method, food components were classified into three groups: group A, strong interaction with the lipid bilayer; group B, weak interaction; and group C, neither A-nor B-type interaction. The sensorgrams of group A showed gradual binding and slow dissociation from the surface of the lipid bilayer. In group B, the food components showed rapid binding and rapid dissociation from the lipid bilayer. The compounds in group C exhibited weak binding to the lipid bilayer, but parts of these samples formed rigid complexes with the lipid bilayer. Sweet proteins producing prolonged sweetness perception as well as miraculin with its taste-modifying activity were classified into group A. The sensory activities of these substances are probably induced by their strong interactions with the epithelial cell surface; they have distinct binding constants with the lipid bilayer. Thaumatin exhibited the strongest interaction, followed by monellin and miraculin.