Food allergy is an immune system reaction to a food. MedlinePlus describes the most common food allergens; sulfites are not listed among them.
FoodSafety.gov notes that some foods can cause abnormal immune responses. Sulfiting agents are used as preservatives in some dried fruits, wines, and processed foods.
Some people — particularly some with asthma — react to sulfites. Read ingredient lists if you have been advised to avoid sulfiting agents.