I have a DD with food allergies (egg, peanut, almond) so I understand. I know I was given teh number of the head chef of DL. I called, left a message, and he personally called me back to discuss my DD's situation. I cannot remember how I got the number, so I would call the Disney Dining number and ask how to speak to someone about food allergies and ingredient lists.
You can also, in any food area, ask to speak to a Lead. That person will put you in contact with the chef who can answer any questions.
We had breakfast at the Minnie and Friends breakfast in DL and the chef made her toast (not on the menu) since she couldn't have any of the other offerings.
We had lunch at Ariel's Grotto and I found out that they do not make the food there. It is made at DLH and brought over, so they couldn't alter any recipes. They did, however, have ingredients lists and were able to find a safe food for her.
Disney is very accomodating and understanding about food allergies.
Have a great trip.