After wasting a lot of time searching for "mother of vinegar" culture (which I found but decided wasn't worth the money or effort required to order it) and trying to make vinegar from unpasteurized store bought vinegar, I had an inspiration that had the combined effect at once causing me to feel clever and embarrassingly dumb.
A few weeks ago I was setting up to make another batch of sour dough starter. It's a mostly a no- brainer process that I've been doing weekly -for years. All I do is mix some organic flour, and water, let it sit on the kitchen counter (next to my stand mixer, of course) for 24 hours, then add more flour and water and let is sit for another 24 hours. During this time the yeast that is naturally present in the flour convert starches into sugar, carbon dioxide and alcohol, while the also naturally present lactobacilli convert some of the sugar into sour tasting lactic acid.
So I'm mixing the stuff up when I remember that there are going to be a lot more microorganisms in the flour than just one species of yeast and one of bacteria. Perhaps at the end of fermentation in addition to a lot of alcohol producing yeast, there would also be a lot of the alcohol consuming acetic acid producing bacteria that are used to ferment wine into vinegar?
In other words all I had to do to turn the bottle of funky Cabernet sitting in my pantry into vinegar was drop in a blob of fully fermented sour dough starter, aerate it everyday for a while and that was it?
Yeah well, it worked. So all that fussing, all the emails to colleagues asking for advice all the search strings for "mother of vinegar," "acetobacteria" and so on, were largely a waste of time.
The answer to the problem was sitting on my kitchen counter all along.