Making apple cider vinegar from apple cider or apple juice is easy. The biggest ingredient is time.
Since the time of Hippocrates (he of the famed Hippocratic Oath), vinegar has been recommended as a health tonic with an astonishing breadth of benefits including joint and bone health, healing infections, weight control, memory, digestion and more. And of all the vinegars out there, none may be more widely praised for these purposes than apple cider vinegar. It is also frequently used in pickling and in many recipes.
Apple cider vinegar, unsurprisingly, is made from apple cider. You can actually make vinegar from nearly any fruit, but with the preponderance of apples in America (particularly the preponderance of apples rotting – uh, fermenting – before they can be harvested for any other uses), it's equally unsurprising that apple cider vinegar has become the fruit vinegar of choice for our culture.
The Basic Process
To make apple cider vinegar, simply leave an open container of apple cider out to ferment naturally. First it will turn into hard apple cider, with enough of an alcohol content to make most people a little tipsy. From there it will turn into apple cider vinegar, usually in 2-4 weeks.
Perfecting the Process
Since the vinegar fermentation process is an aerobic one, you want as much of the surface area of the apple cider exposed to the air as possible. For that reason, use the widest mouthed container you can get.
Then protect that opening from insects and debris by covering it with a cheesecloth. Don't worry -- a cheesecloth or other mesh covering will let sufficient air through for the vinegar to breathe just fine. Secure the cloth with a rubber band.
How to Know When It's Done
Although it could take several weeks to a month for your vinegar to be finished, you should start tasting it after just a few days, and every few days after that. Each batch of vinegar will take a slightly different length of time to reach its desired flavor, even if you perform every step identically each time. Tasting it is how you ensure quality and keep from fermenting it too long (or not long enough) before bottling.
Taste should, in fact, be the prime determining factor on when your vinegar is done. As the wild yeast in the air continues to feed on the sugars in the cider, it will go through a variety of stages. First it will taste carbonated. Then, as both the sweetness and bubbling flatten out more, it will start to take on an alcoholic taste with a dry texture. And finally, as more of the acids develop, a vinegary sourness will start to take over.
For a milder vinegar, bottle it sooner, for a stronger vinegar, leave it longer. At a certain point, however, it will ferment as much as its going to ferment and should be considered done.
Can You Use Apple Juice?
Yes, you can even use apple juice to make apple cider vinegar, if you prefer (typically for reasons of cost or availability). It'll just take longer.
Just be sure, whether you use apple cider or apple juice to make your vinegar, that you use an all-natural variety without any added preservatives, as these preservatives will impede the fermentation process.
More Vinegar Recipes to Try
If you like making flavored vinegars for cooking, here are a few more vinegar recipes to try:
And if you like apple cider, be sure to try our Apple Cider Recipes
So, try making apple cider vinegar, and let us know how it turns out!