Monday, August 07, 2006

Beer Tips: How long does beer stay fresh in a growler?

So, you have a growler and you don't think you can finish it tonight. How long will it stay fresh? Well that's a matter of how much you drank, where you are keeping it and well, whether you like flat beer or not ;-) You'll get the best results if you;
  • don't drink any of it when you bring it home
  • keep it in a cold place
  • make sure it was filled as close to the top as possible ruducing air exposure and surface area for the CO2 to escape from
Keep in mind I haven't tested this theory past two days. I mean...it's pretty hard not to touch a full growler for two days ;-) Of course if you do open it, the clock starts ticking. The carbonation will start to fade and the oxygen (I think that's right) will start to change the taste of the beer. I've kept growlers around for up to five days after they were opened and it just gets flatter and the taste changes a little. So, it's your call. Keep it as long as you like. I wouldn't serve beer from a half a growler to guests if it were there for more than a day. Unless it was Scott ;-)

7 comments:

SeattleBeerGuy said...

I've also found that carefully storing the growler upside down will keep it less flat after it's been opened. I've happily sipped a growler for 3-4 days by using this method.

Adam said...

Hmmm...never heard of that. I guess that might help keep air from seeping in the cap, interesting.

Al said...

A bartender at Long Valley Pub and Brewery once refused to sell me a growler of their porter because it "doesn't travel well".

I don't think I've ever kept a growler for more than a couple of days. It does obviously last longer the less you open it.

eli said...

upside down, eh? I'm going to have to try that.

Adam said...

There are a few things to consider.

Oxidation
O2 gets into the beer and somehow changes the flavor. Can be reduced by decreasing the amount of O2 that comes in contact with the beer. Don't let air in.

CO2 emmission
The larger the surface area the more chance for CO2 to be emitted. More air molecules to bounce off the surface of the beer. Also, since growlers are not filled under pressure the CO2 gas will escape faster due to lesser surface pressure.

Temperature
Less of an issue with gradual changes, but, don't leave it in the sun. Warm beer is more active like warm soda so it will loose CO2 faster in partially filled growlers. Like a pouring a warm soda and getting lots of bubbles.

Light Struck
Light breaks down the hops in beer. The byproducts of that reaction smell skunky. Brown growlers are better than clear or green (are there green ones?).

Of course I can't put all that into any kind of formula. That leaves us with our experiences. So here's my summary...

Get your brown growler filled to the top.
Keep it cold.
Keep it out of the sun.
Drink over a short period of time.
...and perhaps store it upside down.

Your mileage may vary ;-)

Bryan said...

I approach growlers from the opposite perspective...that is, how fast can I drink it!

Sorry, sarcasm aside, I usually prefer to buy growlers of beer only when I can be sharing them with someone (usually Adam, Patty, and/or Matt right?) So, if there's still any beer remaining in a growler after 36-48 hours, then someone must not have shown up to share it with me!

Brian (The Roaming Pint) said...

I know this is an old post, but I have been using the Hydro Flask stainless teel growler lately and it adresses the issue of light and heat.

Being stainless stell it is opaque and thus blocks out light. With it's dual wall vacuum cavity it keeps temperatures steady MUCH longer than glass growlers.

I've used it for as a water container in the past and keep ice unmelted for two days without refrigeration.