If you’re saving wine to use in cooking, be sure to store it in the fridge, and try one of the tips below to keep it even fresher.
• Lubricate the cork by dipping it into a bit of wine and quickly tamping it down into the bottle.
• The less air in the bottle the better, so decant the wine into the smallest possible container.
• Use a Vacu-Vin to suction the air out to slow deterioration, but know that subtle nuances won’t be preserved. The more wine left in the bottle, the better the Vacu-Vin works: you don’t need as great a vacuum, so fewer aromatics get pulled out of the wine.
• Or use Private Preserve (which I vastly prefer), a product that sprays the wine with a blanket with nitrogen, carbon dioxide, and argon, which is much more effective for preserving nuances.
Wine preserved by any of these methods will likely still be good enough for cooking after a week, but you’re better off using it in three days or so. The wine is too old to cook with if it has a musty, stale, or oxidized odor (which might smell like dry sherry) or smells like cooked or dried fruit. It will taste tired, faded, or off: sometimes the tannins, acids, or both taste particularly astringent or strong.