The food experience is described as ten effects: affliction, diarrhea, vomit, misery, tired, grumpy, no effect, sated, happy and elated. Whatever the rolled result may have been, the culinary artist improves this effect by one degree: affliction becomes diarrhea, diarrhea becomes vomit, vomit becomes misery and so on, up through happy becoming elated. Naturally, this provides a comparative improvement in the diner’s well-being.
Because the skill adds to the previously existing cooking ability, this enables a culinary artist to have a 50% chance of producing elation in the diner, even when the food would have been originally mouth-watering in the hands of an unskilled person.
Note, however, that the effect cannot exceed the best possible result at that level of taste. The effect of tasty, for example, could not improve to "sated."