Why does Boxed Wine have an Expiration Date?
Bottles Last Longer than Bags
Boxed wine, which is actually bagged wine slipped inside of a box for ease of transport and storage purposes, has a porous wrapping. Thin plastic is microscopically porous, whereas glass is not. This means that air slowly passes into the bag containing the wine. Air then oxidizes the wine over time.
Boxed wine is sealed into food safe bags that do a great job of keeping the wine from leaking out into the box, but cannot completely cut air off from entering into the bag. These bags and the boxes in which they are contained are both gas permeable, meaning that they have microscopic holes through which air can slowly seep inside and begin to damage the wine. Over time, generally about a year after production, enough air will have entered the bag that the process of oxidation will begin to affect the taste of the wine.
As we mentioned above, these bags are food safe – meaning that there is not danger of chemicals entering the food from the bag when stored properly. The proper storage place for boxed wine is cool and dark. The refrigerator actually works fine for both white and red varieties of box wine.
What About Open Wine Boxes?
Although boxed wine has a shorter shelf life than bottled wine when both are properly sealed, it is a different story once the seals are broken. The bag of wine has an attached pour spout that keeps the wine air tight after opening (aside from the already porous bag). So, far more air will enter an opened bottle of wine (and thus begin oxidizing the wine remaining in the bottle) than a tightly resealed bag of wine. For this reason, things switch and the open bottle of wine now has a far shorter shelf life than the opened box of wine. The maximum time that wine can be enjoyed from an open bottle is up to a week, whereas an open box of wine can remain tasty up to about 6 weeks.
By the way, we tried this box of wine on one of our Monday taste testings in December of 2018, almost three years after the pack date. As suspected, it was overwhelmingly oxidized. I knew for sure as soon as I poured it. I noticed that the color of the wine in the glass almost matched the tan color of the cutting board it was placed upon (see above picture). Sniffed it anyway… there were no hints of fruit or oak… the aroma was not a pleasant one. I still gave it a small taste and quickly spit it out. Yuk (and I am not a wine snob)!
We don’t recommend trying this one at home! We recommend using up wine boxes as soon as possible after a year has passed beyond that printed production date on the box (or shortly after the use-by date if there is one).