There are two ingredients require to make 'mother' vinegar.
Obtain some good wine yeast, mix it with wine and let it ferment.
Keep this liquid by occasionally adding wine. This vinegar can be
mixed with other wine to form vinegar.
Vinegar is an acetic acid solution in water (5-9 %).
For nondistilled vinegars (cider vinegar, wine vinegar, malt
vinegar, balsamic vinegar, etc.), other compounds will be present;
these are what give the vinegar its particular flavor and odor.