That would be a great feature, but I don't think it's available, at least not in the free Fitday version. I'm also trying to track when I eat what I eat, and for now I'm using the Journal, where I write a quick note as to the contents of each meal (e.g., "1030: apple, peanut butter, carrots"). I'm trying to be detailed because I may go to a nutritionist or other healthcare provider in the near future and would like to have a detailed food log. I figure I can print out each journal and daily food log, along with my mood information if I'm really ambitious.
It is a lot of work, though...