Likely for me the sulfur not dealt with like in most folks system gets in my blood stream, into my lungs and is exhaled. Garlic, cabbage,dark green leafy vegies, eggs etc have high sulfur amounts (but they are essential foods). Sulfite preservatives/ sulfites in their many forms are in tons of foods and drinks and cause a worse problem -- beer, wine, cider, bottled lemon juice, dried fruit, etc etc even some spirits as the kegs they age in are sometimes treated with sulfur. Aged whiskies not so bad as I'm told the sulfur content tends to dissipate. It may seem odd to have such a reaction with such a small amount of sulfite ingestion -- possible one cause may be a genetic one - in my case. Lessening the consumption of the above helps -- though you'd need to be advised from a medical/diet practitioner...