Vinegar is a sour liquid used as a condiment or as a preservative. It is obtained through the fermentation, or the artificial oxidation, of ethanol.
According to an alchemical work dating back to the 1550s, vinegar is used in the making of the perfect medicine, along with Salt, Urine, Sal Ammoniac and a particular Sulphur Vive.
Turning vinegar back into wine (and thus reverting the fermentation/oxidation process) is part of the sixth year Charms curriculum at Hogwarts School of Witchcraft and Wizardry.
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