Relationship between preference and gaze in modified food using eye tracker.

PURPOSE: The relation between preference and the gaze for the test foods under unconsciousness using the eye-tracking system was investigated.

METHODS: Participants consisted of 37 healthy volunteers. Test foods were steamed rice 150g, grilled salmon approximately 45g and slice cooked squash 60g, all of which were served on a tray. Foods forms were regular food, chopped food, and blended food. After attached to the eye tracker, participants watched the each dish arranged in front of them freely for 10s. And they ate test foods freely within 10min. The gazing point was measured for 10s from the time when the food was ordered and just before the eating. Preference levels were interviewed. The number of gaze point fixations and the total gaze point fixation time of the viewpoint during 10s just before eating were analyzed. The analysis items were (1) the total number of gaze point fixations (2) the total gaze point fixation time (3) the amount of food intake and (4) the preference level details.

RESULTS: For foods with higher preference levels, the number of gaze point fixations increased significantly and the total gaze point fixation time significantly increased. In both groups, maximum food intake was observed for food forms with a high preference level. Most of the participants' selected regular foods as their most preferred food form among the food forms.

CONCLUSIONS: The results suggested that subjects gazed at regular food which had high preference level.