<<Disclaimer: Verify this information before applying it to your situation.>> I am sorry I am late in getting this summary to the list. I had received a response from Robert Rothschild Gourmet Foods in which they stated that their Balsamic vinegar was not gluten-free because it has sulfides in it. The concenses from the replys that I received was that sulfides do not contain gluten. Several thought the rep or vendor were mistaken which is what I was feeling. A few people mentioned that, while they did not believe there was gluten in Balsamic Vinegar, some people had an allergic reaction to it. One person sent the following definition of sulfides: In the Comsumer's Dictionary of Food Additives, by Ruth Winter, MS... Sulfides: inorganic sulfur compounds that occur free or in combination with minerals. They are salts of weak acid & are used in dyes and hair dissolving agents in depilatories. They are skin irritants. Judy Smith Kent, WA