Too much beer is hardly a bad problem to have, but there are times when, yes, you open a bottle and realize you can't finish it. This often happens to me when I open large 750 mL bottles of specialty (and quite often very alcoholic) beers. Unless I open it with friends, it's just too much for one sitting. I used to worry that the leftover would go to waste, but now I just save it for later.
I first realized that beer could be saved when I started buying growlers from a local brew pub. Concerned that I'd need to drink the entire growler right after buying it, I asked the bartender how long the beer would keep. She said it would gradually lose carbonation each time I opened the growler, but would keep perfectly well for several days in the fridge.
I remembered this the next time I found myself with a leftover bottle of beer, and tried sealing it with an old wine cork. The next day, the beer was slightly less bubbly, but still frothy, flavorful, and most certainly drinkable.
I've since come to rely on rubber stoppers and a vacuum pump — the same I use for preserving a half-full bottle of wine. Once secured with the vacuum sealer, these stoppers keep an airtight seal and seem to work very well at holding CO2 in the bottle. (Careful, though: if the bottle is still more than three-quarters full, it can sometimes froth up when you pump the vacuum sealer.)
Sealed and refrigerated, I find that a bottle of beer will keep fairly well for about three days. After that point, the beer starts to taste too flat to be enjoyable to drink.
• Wine Bottle Vacuum Sealer Pump with 2 Stoppers, $4.20 from Amazon.com
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great idea!
I've always had good enough results with Parafilm. I suppose if you drink wine, corks and vaccum sealers might be an easier fix, but if you do science (or know someone who does), a square of parafilm pulled tight over the opening will keep beer for about a day (which is when I'd want to finish it anyway).
I use those vacu vin stoppers as well for half consumed bombers/750's, though I don't use the pump with it as creating a vacuum will cause the beer to lose carbonation faster.
mmm the bruery...
lovely choice!
...leftover beer?
A simple trick I learned a few years ago for pry-off caps: if you place a U.S. quarter (or similar sized coin) over the cap before you use the opener, the cap doesn't bend and can be popped right back on the bottle. It won't keep it air-tight, but it's good enough to preserve some fizz for the next day or so.
This has revolutionized my scrumpy-drinking! My preferred scrumpy comes in a bottle too big for me to comfortable enjoy in one sitting, but now that I know I can easily re-cap it, I'm happy to buy that big bottle.
Yet another reason it pisses me off that breweries don't package in 12 ounce bottles and cans. The other main one, of course, is the prices they charge for the "privilege" of wine-sized bottling. Compare your favorite Bruery beer on a per ounce basis against a comparable quality 12.
@alicelost: so glad to hear someone else is stealing parafilm from the lab and using it in the kitchen :) also, hemostats.
Use champagne stoppers. They're designed to keep the champagne bubbly and work great for keeping beer carbonated too!