This article is a part of Wine Week\u2014seven days celebrating all things wine\u2014presented in partnership by our friends at Bread & Butter Wines<\/a>.<\/em><\/p>\n Internet memes may tell you \u201cthere\u2019s no such thing as leftover wine\u201d\u2014a joke about drinking that misses the point that, very often in daily life, we might not finish an open bottle. If we do have leftovers, the conventional wisdom is that the clock is ticking, since wine is best the same day it\u2019s opened, or should be consumed by the next day at most. This is frustrating, though, if you don\u2019t want to drink that opened wine the very next day or if you don\u2019t have the chance, especially when the leftovers are of a great quality. And pouring \u201cold\u201d wine out feels like a waste. Many of us will ask under these circumstances, But how bad can it be?<\/em> Understanding how long an open bottle of wine lasts is key to making the most of every last drop\u2014before it turns into vinegar.<\/p>\n The process that starts when you open a bottle of wine is called aeration, which leads to oxidation, which \u201cincreases color change and the loss of fruity characteristics,\u201d according to professor Gavin Sacks, Professor of Enology and Viticulture in the Department of Food Science at Cornell University. It also \u201cleads to the loss of sulphur dioxide, which preserves the wine,\u201d he says, and dissipates aromas. Even if you put the cork or a wine stopper back in, the process continues, since no closure is airtight and oxygen has already been introduced.<\/p>\n The great news is that although it\u2019s not good in large doses, in small amounts, oxidation can be welcome, or even beneficial, to a bottle of wine. It occurs naturally inside the barrel and bottle when the wine ages. Sometimes if a fine wine hasn\u2019t aged enough (meaning it still tastes overly tannic and astringent), experts will decant it or allow it to aerate for a few hours. This helps optimize the flavor by making it mellower and can allow unwanted aromas to dissipate. Swirling one\u2019s glass may look showy, but it is also a practical way to aerate. These are positive examples of allowing a wine to \u201copen up\u201d or \u201cbreathe.\u201d And even with some medium-quality bottles, wine-nerdy people will open them and taste over the course of a few days, to watch how the flavor changes over time.<\/p>\n Thus, if you can control the oxidation, you can sometimes drink a bottle of wine up to a week after opening it, depending on a number of factors such as how full the bottle is, the light exposure, the temperature at which the wine was stored, and what kind of wine it was in the first place.<\/p>\n The following can help you judge how long an opened bottle might still be drinkable. For our purposes, we are assuming that you don\u2019t have any fancy wine preservation gadgets, such as a Coravin<\/a>, and that you want your wine to taste not just good enough<\/em>, but still very good.<\/p>\n
\nWhat Is Oxidation?<\/h3>\n