Can I eat canned or frozen fruit if I'm allergic to fresh fruit?

I have full blown allergies to some fruits (apples, peaches, pears, plums, grapes) and I cannot eat them as juices, in jams, pies,  marinades, or in wines or I get really ill-- at the very least vomiting, bad itching and redness, heat everywhere, just bad.. Sometines starts to affect breathing too and I carry epipens abd benadryl along with my asthma inhalers. I avoid these foods strictly (along with nuts). My son has some full blown allergies and some OAS/pollen-food syndrome. Usually cooking the foods helps but not always. It depends on how bad his seasonal allergies are that cross-react with the problem food. We avoid the food afterwards until we think the season might be over with and then try it again. I always tell him, if it makes you feel bad, it is best to avoid it. If it makes you feel really bad or is a full blown allergy, then definitely avoid strictly.  And if you want to see if things change over time, do not test it on your own, we can go do a test or food challenge at an allergists.