Contextual Visual Cues in Dessert Evaluation: A Mixed-Effects Analysis of Plate Color Effects on Sweetness and Bitterness Perception.

Flavor perception is a multisensory process shaped not only by foods' physicochemical properties but also by contextual cues that influence consumer expectations. Plate color is one such cue, yet evidence remains limited for desserts rooted in Latin American culinary traditions. This study examined whether plate color (red vs. black) alters perceived sweetness and bitterness in cacao- and passion fruit-based desserts. Using a randomized within-subject crossover design, adult consumers evaluated products served on both red and black plates and rated sweetness and bitterness on 100-point visual analog scales. Sourness, overall liking, and consumption intention were also collected for complementary purposes but were not included as primary outcomes in this analysis. Data were analyzed using linear mixed-effects models to account for repeated measures and individual-level variability. Results revealed a significant plate color × product interaction: red plates increased perceived sweetness in the passion fruit-based dessert, whereas black plates intensified perceived bitterness in the cacao-based dessert. Food neophobia did not significantly moderate these effects. Overall, the findings demonstrate that plate color systematically modulates reported taste intensity in a product-dependent manner. These results extend evidence on color-taste crossmodal correspondences and provide practical insights for sensory-driven food presentation and product design.