If you’re tallying a list of the terrible fates that could befall a human being, having your leftover Champagne go flat ranks somewhere between “minor toe cramp” and “having to sign for your neighbor’s package because they’re not home.” Still, you paid for the stuff and you’d like to enjoy it in its optimum state of effervescence. Of course it’s never again going to be as fresh as when you first popped the bottle (and don’t even think of putting Champagne through a Sodastream unless you reeaaallllyyy love mopping), but it’s entirely possibly to take a few preventative measures and maintain or revive a whole lot of that fizz—ideally for drinking at brunch on New Year’s Day.
It may be difficult to keep stock of all your bubbly in the middle of a shindig, but if you possibly can, only open one bottle at a time, keep the rest in the refrigerator or in a cooler, and make sure that any opened bottles stay on ice. The carbon dioxide that gives sparkling wine its fizz is more soluble at low temperatures, so the longer it stays cold, the long it will hold onto the dissolved gas. Once it warms up, bye bye, bubbles.
Put a cork in it
The original cork from a bottle of sparkling wine has long since gone kablooey. You either sabered it off (a la our colleague Maxine) or popped it out in a loud and festive manner. But seeing as its expansion against the neck of the bottle was the primary force in keeping the fermented liquid from escaping, it’s done its job and is hanging out across the room, expanding like it’s been dying to do for a while. It’s not gonna fit back in the bottle, but all is not lost. Invest a few bucks in a Champagne stopper—a tiny device that clamps onto the top of a bottle and expands within to keep the gas intact therein. You could do this at the end of the night, or get all fetishy and keep one or two on the table so guests can pour and reseal on the fly. (Note: You might consider keeping a few on hand because they tend to find themselves snuggled into the pockets of tipsy, dazzled guests.)
A raisin to live
Champagne is made from grapes, so it’s sorta circle-of-life-ish that a shriveled up one will bring it back from the near dead. (This won’t work if it’s completely flat—save that for salad dressing.) A moment or two before pouring, drop a raisin into the bottle. The remaining carbon dioxide will cling to all those crinkles and ridges, then release back into the liquid, making it fizz up again. It’s a New Year’s Day miracle!