(Not to be taken) with a grain of salt: Enhancing perceived saltiness by 3D-printed surface textures

Seeking to promote healthy food options through design, this study investigates whether food saltiness perception can be enhanced through the design of the surface texture of the container from which the product is sampled, using 3D-printing. An experimental study was conducted at a supermarket in which shoppers (N = 270) participated in a taste test. A full-factorial 3 (surface texture: smooth, rough, rough and irregular) × 3 (salt content: low, medium and high salt content) between-subject design was employed. Participants in each condition were asked to try the product and assess saltiness perception, taste intensity, taste liking and willingness to try. Results testify to the feasibility of enhancing saltiness impressions through both rough and irregular 3D-printed surface textures, but only for the medium-salt and high-salt variants. Findings on taste liking and willingness to try likewise testify to the importance of considering the interaction between surface texture and saltiness. These findings qualify previous research on cross-modal correspondences by showing that applications of surface textures may backfire when the gap between expectations triggered by tactile sensations and actual food contents becomes too large. Implications for initiatives aimed at promoting healthy food choices are discussed.