In summary, vinegar’s key ingredient is alcohol. The transformation of wine or fruit juice to vinegar is a chemical process in which ethyl alcohol undergoes partial oxidation that results in the formation of acetaldehyde. The acetaldehyde is converted into acetic acid. The global demand of acetic acid is around 6.5 million tons per year (Mt/a), of which approximately 1.5 Mt/a is met by recycling; the remainder is manufactured from petrochemical feedstocks or from biological sources. And this from Alcohol, Tobacco and Firearms Division, Internal Revenue Service :“Presently, we authorize the manufacture of vinegar from ethyl alcohol synthesized from natural gas or petroleum derivatives. It is our opinion that most of the distilled spirits used in the production of vinegar are derived from natural gas and petroleum…” Now, don’t ask me why the ATF and IRS are involved in this whole thing. I don’t think I really want to know, but the point is about 75% of the vinegar on the market is made from a petroleum derivitive. BUT!!!!! The author of the post at Tiny Changes (the link above) did some research and found that Heinz uses only fermented grains for its white vinegar and apples, of course, for its cider vinegar. So, I guess I need to check the label on my cheap Walmart brand vinegar and if it is, indeed, made from petrochemicals, then I’ll be patronizing Heinz.