Explicit and indirect behavioral responses to plant-based foods across processing levels: An adaptation of the Leeds Food Preference Questionnaire

This study aimed to examine consumers' explicit preferences and indirect behavioral responses to plant-based products differing in processing level, using an adapted version of the Leeds Food Preference Questionnaire. Sixteen food images were selected to represent either legume-based or cereal-based products, each presented at two processing levels (low vs. high). The categories—Highly processed cereals (CerPro+), Low processed cereals (CerPro-), Highly processed legumes (LegPro+) and Low processed legumes (LegPro-)—were represented by four images each. A total of 196 French non-vegetarian consumers completed a two-stage task: (i) explicit ratings of liking and wanting for each food image and (ii) a forced-choice task comprising 96 pairs of images, in which the participants had to select, as quickly as possible, the product they most wanted to eat at the moment. Results showed that explicit liking and wanting were higher for cereals than for legumes, with no significant differences between the two levels of processing. In the forced-choice task, cereals were chosen more frequently than legumes, and reaction times were significantly shorter for cereals than for legumes. Although choice frequency did not differ across processing levels, reaction times were shorter for highly processed products. A composite behavioral index was calculated and was significantly higher for CerPro+ and lower toward LegPro-. Overall, these findings suggest that processing level is associated with differences in choice behavior and decision speed, even when explicit ratings are unaffected. They further indicate that processing level may influence behavioral components of food preference that are not captured by self-report measures.