Boxed wine does go bad but it stays fresh between 30 to 60 days after opening. Boxed wine are basically wine that is contained in a bag with a cardboard box outer covering. To dispense the wine, a hole is cut along a dotted portion on the box and a spout or a tap is pulled out through the hole.
Boxed wine may contain a 750 ml wine or as much as three to five liters of wine. Once wine is exposed to oxygen, the wine will start to turn. How long wine lasts after exposure to oxygen varies according to the quality and fragility of the wine.
Boxed wine holds an advantage over bottled wine when it comes to controlling its exposure to oxygen because the bag containing wine stays inside the cardboard box even when wine is being dispensed. The bag also collapses in the box, restricting the amount of air that can enter, making the wine last longer. In comparison, bottled wine lasts only a few days until the flavor is affected after the bottle has been opened.
Another advantage of boxed wine is that it is usually cheaper than bottled wine. On average, the price of a three-liter container of boxed wine is equivalent to about four to five bottles of bottled wine.