Sherry vinegar is made from Sherry, a white wine made with brandy from grapes grown near the Spanish town of Jerez. Because of this, you’ll often see the words “Vinagre de Jerez” on bottles. For this label to be on the vinegar, it must have been aged for at least six months. To make sherry vinegar, the Sherry is first turned into acetic acid. Acetify is a fancy word for letting the Sherry get exposed to air so that it starts to turn into vinegar. The old and new vinegar are then mixed to make sherry vinegar.