Have you considered that it could be sulfite sensitivity?
Sulfites, or sulfiting agents, are sulfur-based substances
Six are used by the food industry: sulfur dioxide, sodium sulfite, sodium bisulfite, potassium bisulfite, sodium metabisulfite and potassium metabisulfite.
Sulfite sensitivity may be caused by a relative deficiency of the enzyme sulfite oxidase which breaks down sulfites and requires molybdenum as a cofactor. As with lactase deficiency, this is a metabolic problem and not an allergic one.
Foods that may contain sulfites (partial list):
* Alcoholic Beverages (labeling of sulfites in alcoholic beverages is required if the concentration is 10 parts per million or greater.)
* Bakery Items: Breads containing dough conditioners, cookies, crackers, pie and pizza crusts, tortillas, waffles.
* Beverages: Beverages containing sugar or corn syrup, dried citrus fruit beverages, canned bottled, and frozen fruit juices.
* Condiments: Horseradish, relishes, pickles, olives, wine vinegar.
* Dairy: Processed cheese foods.
* Dried Foods: Dried herbs and spices, dried fruits, trail mixes.
* Fish and Shellfish: Fresh shrimp and scallops frozen, canned or dried clams, shrimp, lobster, crab, scallops, dried cod.
* Fruits: Fresh grapes, dried fruits (including raisins and prunes and especially pale fruits that have not discolored), canned, bottled and frozen fruit and juices, maraschino cherries, glazed fruit.
* Gelatins, Fillings, Frostings: Fruit fillings, flavored and unflavored gelatin, pectin, jelling agents, canned frostings and frosting mixes.
* Grain Products: Cornstarch, modified food starch, spinach pasta, gravies, hominy, breading, batters, noodle and rice mixes.
* Hard Candies
* Jams and Jellies
* Nuts: Shredded coconut.
* Plant Protein Products: Soy protein products including tofu, textured vegetable protein, infant formula.
* Snack Foods: Filled crackers, dried fruit snacks, trail mixes, tortilla chips, potato chips.
* Sugars: Brown, white, powdered and raw sugars.
* Vegetables: Vegetable juices, canned vegetables (including potatoes), pickled vegetables (including cauliflower, peppers, sauerkraut), “fresh cut” potatoes (as delivered to restaurants), frozen vegetables (including french fries and deli potato salad).