<<Disclaimer: Verify this information before applying it to your situation.>> SUMMARY Thanks to all of you who provided prompt responses. I learned--just in time for Evan's lunch!--that Heinz ketchup is made with white vinegar from *corn*. Its gluten-free! For anyone who wants to avoid all white vinegar, Tree of Life brand ketchup is made with cider vinegar and may be available from your health food store. ...Pam