In a study for the Journal of Sensory Studies, researchers at the University of Oxford have reported that "the color of the container where food and drink are served can enhance some attributes like taste and aroma." The scientists performed the study on 57 volunteers, serving them the same hot chocolate in different colored cups. The subjects reported that the hot chocolate tasted best in orange and cream-colored cups. Previous research has associated yellow cups with enhanced lemon flavor in soft drinks. This is why I've always said that blue M&M's are the best.