1. A computer-implemented process for evaluating images of meals, comprising: using a computer to perform process actions for: receiving a meal image of a single meal consisting of multiple food items; wherein one or more of the food items are occluded in the meal image; receiving information indicating a source of the meal; recognizing one or more of the visible food items and one or more of the occluded food items in the meal by evaluating the meal image using a machine-learned meal model that is constrained by the source of the meal; and presenting one or more interactive messages automatically generated based on the recognized meal.