How to Make Wine Vinegar

I bought an inexpensive, but what I hoped might be, an enjoyable bottle of Zinfandel for us to have with dinner recently. The wine was disappointing. We were going to go ahead and finish it, but since we really didn't like it, we decided to experiment with it and try to make a little bit of red wine vinegar with what was left. Why not? Yes, you can get wine vinegar at every grocery store and it's cheap, but like you, we like doing things ourselves. 

In it's simplest form wine vinegar is just wine gone "bad". Let it sit open for a couple weeks and eventually the alcohol will evaporate and the wine will oxidize into vinegar. But there are more structured ways. I’ve read in different resources, that you do not need 'mother of vinegar' to make your own batch. Mother of vinegar is a 'slimish' looking substance composed of a form of cellulose and acetic acid bacteria that develops on fermenting alcoholic liquids, and acts as a starter to turn alcohol into acetic acid - vinegar - with the help of oxygen from the air. While not appetizing in appearance, mother of vinegar is completely harmless. You can use unpasteurized vinegar to use as a starter. I used Bragg’s organic unfiltered vinegar, because we always have some and it contains a mother naturally. 

There was about a cup of the zinfandel left but this can be scaled for any amount of leftover (or even just-opened) wine.

Ingredients:

1  cup wine

3  tablespoons starter vinegar, use a living variety. Bragg’s is readily available

Directions:

Pour your leftover (not from other people’s glasses) wine into a container with a large surface area, like as a bowl.

Add starter vinegar

Stir it all up

Cover with a towel and let it sit, stirring when you think of it, for a month. 

With small amounts like this, start tasting it at 3 weeks. It can take longer than a month, though.
Once it tastes like vinegar and not like wine, move it to an airtight container, with very little surface area exposed.  Swingtop and sealable wine bottles of the appropriate size work great.  

Although air is critical to the process of vinegar fermentation, continued exposure to air once you have your vinegar is a good way to ruin it/make it not be vinegar any more.