Integrating Eye Tracking and Self-Report for Sensory-Emotion Evaluation of Red Bean and Coix Seed Water: A Complementary Validation Framework.

To examine whether gaze behavior on the rating scale can complement conventional self-report, twenty-four volunteers evaluated three red bean and coix seed water beverages on sensory attributes, EsSense-based emotional terms, and preference, while their fixations on the response scale were recorded using a synchronous area-of-interest design. Two indices were extracted: the questionnaire rating (QR), reflecting the consciously selected score, and the eye tracking-derived rating (ETR), defined as the longest-fixated score option. QR and ETR were strongly correlated (ICC: 0.88-0.89) and produced an identical preference ranking (R1 > R2 > R3), yet the wide limits of agreement indicated that they are not interchangeable at the individual level. Across the sensory-preference, sensory-emotion, and emotion-preference layers, QR consistently yielded stronger correlations than ETR. Warmth and sweetness were positively associated with positive emotions and liking, and "Good-natured" was the most stable emotional correlate of liking. Gaze behavior thus provides a process-oriented complement to, rather than a replacement for, self-report.