Leftover Wine

leftover wine in an opened container such as a half-empty bottle is prey to oxidation and steps must be taken in order to prevent it turning to vinegar—which could happen within hours or even minutes for a very old wine, within two or three days for most young table wines, and fino and manzanilla sherry, and most bottle-matured port, within a few weeks for a robust wood-matured port such as common or garden Ruby or Tawny or oloroso sherry, or within months, possibly years, for most madeira.

Because oxygen is the villain in this piece, the easiest way to avoid spoilage of leftover wine is to decant it into a smaller container, perhaps a half-bottle, which approximates as closely as possible to the volume of wine left. There are also patent devices for filling the ullage in a bottle or decanter with inert gas, by pumping or spraying, or an attempt can be made to create a vacuum with a pump device. Some drop small, inert objects such as glass marbles into an opened bottle to restore the fill level to the bottle neck. Leftover wine, no matter what the container or colour, is best stored cool to slow the reactions involved in its deterioration.