As a general rule, without the use of specific preservation techniques, wines change immediately after opening at room temperature. Usually the wine will be completely spoiled in about 3 days (2 days for white wines).

After 1 day or so, some wines usually become smoother, but those fruity young wines are at their best when they are freshly opened.

On day 2, wines that were re-corked on the first night will be even better, but most of the fruit in the wine will begin to fade and the acidity will become apparent. By day 3, some wines will have deteriorated completely, with the aromas fading and the palate becoming very acidic.

Ideally, wines should be placed flat so that the cork can come into contact with the wine to keep it moist. Otherwise, if the wine is placed upright for too long, the cork will become dry and brittle and will not be able to close the bottle tightly, resulting in oxidization of the wine.

How to store dry red wine after opening:

After opening the bottle: cork it and place it in a cool, dark place.

Red wines with more tannins and higher acidity will keep longer after opening. So some lighter-bodied, less tannic reds will keep for a shorter period of time, although some reds may even taste better after a day in the bottle. You can usually store open bottles of red wine in a cooler or in a cool, dark place, or in the refrigerator if you don't have a cooler, but it's best not to keep them at room temperature (21°C).

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