Kaolid: Lid-type Olfactory Interface to Improve Taste of Beverages with Ortho-Retronasal Smell

There are two nasal pathways through which we perceive odors: “orthonasal smell,” which comes from the tip of the nose, and “retronasal smell,” which comes from the mouth and exits through the nose. In particular, the retronasal smell is known to be more critical in influencing perceived taste than the orthonasal smell. In this study, we propose a smart lid called Kaolid that changes the taste of beverages by presenting scent information as retronasal smell. Kaolid achieves retronasal smell by equipping a small, lightweight straw- or cup-type olfactory device with a sensor that senses drinking behavior and the amount of water in the cup. The straw-type device injects the scent into the tube through the middle of the straw, delivering the scent to the user's mouth simultaneously as the beverage is being consumed. The cup-type device injects the scent into the cup through the lid and delivers the scent to the user's mouth at the beginning of drinking to achieve in-mouth scenting. The concept of Kaolid is to promote water consumption, considered insipid, by altering the sense of taste through a scent presented when drinking the beverage.