The purpose of a fast is to get away from the material and physical and concentrate on the spiritual. Fasting means to afflict oneself. The drink you are describing sounds more like a “dessert” to me. If you’re going to be honest with yourself, you have to admit that the reason you would have such a drink is to indulge your physical senses. That would seem to defeat the reason for fasting. I wouldn’t call that drink an “affliction.”
