I have this issue and was told it was oral allergy syndrome. Basically your body thinks it ingesting pollen and not fruit. I had blood tests as well as the skin test for allergies and the only food allergy that came up was peanuts (which I had no idea about and had eaten peanut butter for years but now even the smell of peanut butter gives me problems)
As far as fruits and veggies I must avoid due to OAS are apples, peaches, plums, nectarines, cantelope, grapes, carrots, celery, peas, cherries, kiwi, and I am sure I am leaving something out. Certain foods on this list I can have if cooked or processed. Foe example I can have apple juice, apple sauce, apple pie etc also carrots if cooked so soft you can mash them with a fork. Some people with this have GI issues some have anaphalactic issues. My issues are as yours and the more I eat the items the worse the reaction gets so I avoid them and carry an epi pen just in case.
Dx with Crohn's 1987, symptoms as early as 1984.
Temp iliostomy February 2007, reversed June 2007, Ovarian cysts, migraines, allergies (incl food allergies) , oral allergy syndrome (diff than true food allergies), Asthma, Gall Bladder removed 1999, Inguenal hernia 1987