The start of our cider vinegar.
Very few people know how vinegar of any type is made. Fortunately for us it is a very simple biological process that anyone can do. If you have a large open mouth glass jar, juice, and a breathable cover you can make all kinds of vinegar types that potentially taste far better than what you buy at the grocery store. The container must be glass, wood, or stoneware because the acid produced (acetic acid) will dissolve metals. Also, the juice must be preservative free but can be any type of juice you want. I have only experimented with apple juice but other juice like grape juice works well also. Experiment with other types of juice or even by adding flavorings of maple syrup, molasses, or honey. Warning though, do not over fill your jar, leave at least a few inches of space between the juice and the jar. If you over fill your jar the juice may overflow and leave a disgusting mess. In order for your juice to turn into vinegar it must be open to the air on the top so your jar must have a large mouth. It is extremely important to cover the jar mouth with some type of breathable cover, if you don't you will quickly have a major fruit fly infestation. And by major I mean lots of flies and lots of potential grossed out people. We have found pantyhose to work best. Other covers such as cheese cloth still occasionally allow fruit flies to access and reproduce on the surface of your juice. But if that happens to you the entire project can be turned into a study of the fruit fly life cycle, something you may or may not have any desire to know about! But we are making cider here, so once everything is mixed and covered up, place the covered jar in a location where it will not be disturbed and wait. The entire process will take four or more weeks and the results will surprise you in more ways than one! It will be extremely stimulating in smell, taste, and sight. Stop by your container every day and observe what is happening.
The juice will not automatically convert into vinegar though some spontaneous generation. Atmospheric microorganisms will inhabit the juice through the breathable cover. First, yeasts and fungi will proliferate in the juice causing fermentation and the production of alcohol. Then, after fermentation is complete Acetobacter sp. bacteria from the atmosphere will inhabit the now alcoholic juice. These bacteria will convert the alcohol into acetic acid and thus your vinegar.
We started a batch of apple cider vinegar yesterday and will be posting the surprising results in a little over a month.