Kegging problem - What Happened?

[EliW]

Ok, so I've been a homebrewer for a long time, but always bottled (either into bottles or growlers)

I recently was going to supply brew for a large party, and so invested in kegging equipment (and honestly, given how easy it all was, I don't ever wanna go back to bottling *grin*)

But, on my first time out, I seem to have had a problem. Here's the situation:

1) I brewed the beer (an IPA in this case), and because I didn't want to deal with refrigeration, I primed in the keg.

2) 4 weeks later, on a Saturday, I take the keg to the event, drop it in a trashcan w/ ice, hook it up, set the pressure at 10psi on the gauge, and start serving. It works GREAT. But only ~3.5-4 gallons get drank. (ok, there were 95 gallons of homebrew at this party, so we didn't get through all of it)

3) Because we were all drinking and it got late, the pressure was left on overnight (just mentioning in case it matters)

4) Next morning, I turn the pressure off, disconnect everything, and bring it all home.

5) Monday evening, I decide I need to work on finishing up that last gallon. I hook the CO2 back up, everything seems fine, and I pour myself a few glasses that evening. At the end of the evening, 'just in case' (hearing horror stories of slight leaks wasting tanks), I turn the tank off. I leave everything hooked up though.

6) Tonight, Wednesday evening, I decide to have another glass. This time, when I turn the valve back on, my pressure gauge claims I'm only at like 3PSI. Odd. I turn it up until I hit 10PSI again, and I hear/feel it feeding CO2 into the keg for a while. Odd.
I go to tap myself one, and it comes out completely flat, and tastes badly oxidized. Like that last glass of beer you left in a growler for a week, then find in the back of the fridge.

So, what happened between Monday and Wednesday?

Thanks,
Eli

 

[Yooper]

That doesn't make sense. If there is no way for oxygen to get in, then it can't be oxidized. Is it possible that someone removed the top, and poured off a sample to take home? Or you had a major bad co2 leak, or another way for 02 to enter? You can keep kegged beer for ages, so as long as there is co2 in there, it can't oxidize.

 

[EliW]

Yeah, I know, it doesn't make sense to me either.

But on Monday it was fine, on Wednesday it was flat and oxidized. That's why I'm scratching my head as well.

The co2 was turned off during that time, though all the hoses were still connected. And noone opened anything, just me and my 6yr old at home.

 

[KevinM]

Unless there was a leak that was occuring somehow, that could vent the pressure, or someone could have pulled the pressure relief valve (but that doesn't explain the oxidation situation).
If there was a leak though, I'd expect that you'd have noticed earlier in the weekend.
We'll probably be drawing random ideas since everything sounds appropriately done. You know, aliens wanting the co2 or something.

 

[Gunfighter04]

I'd guess that you have a poppet that doesn't seat or needs a new seal. with the connector on, it's irrelevent since it's either beer or co2 on both sides of the seal. Without the connector on, air was able to get in. Maybe a piece of hop or something got in the connector. Since the pressure was down to 3psi there's obviously some leakage that occurred.

 

[jmf143]

Even at a low pressure of 3psi in the keg I'd think the force pushing "out" would keep any air from seeping "in". Don't see how oxidation could be the problem here.

 

[EliW]

Gunfighter: But from Monday->Wednesday the connectors were still on. Just the tank was turned off.

I guess I obviously had some kind of leak. It's just a question now of how exactly that leak happened. odd.

 

[fuhmon]

sometimes when drinking from commercial kegs the last couple pints seems flat. usually not oxidized though. very strange. maybe its dregs from the bottom?

 

[Gunfighter04]

Gunfighter: But from Monday->Wednesday the connectors were still on. Just the tank was turned off.

I guess I obviously had some kind of leak. It's just a question now of how exactly that leak happened. odd.

Sorry misunderstood, then I agree that we have a conundrum

 

[EliW]

sometimes when drinking from commercial kegs the last couple pints seems flat. usually not oxidized though. very strange. maybe its dregs from the bottom?

You know, you might have something here. While it 'tastes' oxidized, given it was primed in keg instead of force-carbonated ... I've noticed with this whole batch that almost every pint that came out was rather cloudy (instead of the first pint/two being sludge and the rest clear, as I'd been led to believe

So, perhaps in these last few pints, combined with flatness, it's just the taste of the dregs coming through I'm getting instead.

Thanks for all the help folks

 

[integrator]

I think you just have a leak, and not really an oxidation issue like you just posted. Hunt down that leak.

 

[dex0807]

CO2 is heavier than air so unless the keg was jostled around a bunch with the lid off you will maintain a blanket of CO2 in the keg and have no risk of oxidation over a period of a few days. The only risk you will have without a constant pressure is flat beer.