Confusing tastes and smells: How odours can influence the perception of sweet and sour tastes

This study investigated the relationship between perception of an odour whe n smelled and the taste of a solution to which the odour is added as a flav orant. In Experiment 1 (El) sweetness, sourness, liking and intensity ratin gs were obtained for 20 odours, Taste ratings were then obtained for sucros e solutions to which the odours had been added as flavorants. Certain odour s were found to enhance tasted sweetness while others suppressed it. The de gree to which an odour smelled sweet was the best predictor of the taste ra tings. These findings were extended in Experiment 2 (E2), which included a second tastant, citric acid, and employed four odours from E1. The most swe et smelting odour, caramel, was found to suppress the sourness of citric ac id and, as in El, to enhance the sweetness of sucrose. Again, odours with l ow sweetness suppressed the sweetness of tasted sucrose, The study demonstr ated that the effects of odours on taste perception are not limited to swee tness enhancement and apply to sour as well as sweet tastes. The overall pa ttern of results is consistent with an explanation of the taste properties of odours in terms of prior flavour-taste associations.