Sulfides/sulfites are everywhere - lunchmeat, bacon, ham, yes red wines for sure as it is a naturally occurring substance in grapes. Up until recent years was also used as a preservative in lettuce and bagged salad mixes. Some have a severe allergy to them and have bad reactions especially when used in the salad stuff. Some states have now outlawed the use of them by restaurants...but it did keep the stuff nice and green.