Overcarbonation Paradox

[Epiphanic]

So I was bottling my raspberry half of the saison when I decided to crack open a bottle of the regular half of the same batch that had been bottled for 3 weeks. I did this to check the carbonation because I was slightly worried that I put too much priming sugar in at bottling. This is the third time I've brewed this saison and each time I've primed with 2.5 oz. for each half batch (~2.5 gallons) of sugar and they've come out fantastic each time. And this time is no different. It pours beautifully and tastes wonderful.

What's a little confusing is that my previous batch was a pale ale that I primed with 3.7 oz. for the full 5 gallons foams up like the dickens when you pour it. It doesn't gush up when you open it, but if you open a bottle and you let it sit for a while some head might creep slowly out of the bottle after a few minutes. I used less sugar with the pale ale so I don't know why it'd be so much more volitile.

Reading some of the other overcarbonation threads suggest that I may have not allowed the pale ale to completely ferment out prior to bottling, but I doubt it as the final gravity was stable for the two weeks before bottling and it was sitting the fermenter for about 5 weeks total.

It may be just a one off thing. I just thought it was strange enough to share.

 

[zzARzz]

I had a similar issue with a pumpkin ale I did for last Halloween. I rushed it to get it ready in time and when one was opened at room temp it would explode like Old Faithful. Getting it really cold reduced it to the "bottle creep" you mentioned but it was hardly ideal. Looking back it was probably a combination of too much priming sugar and not letting it sit longer as you said.

 

[Obliviousbrew]

Fermentation temperature can be an explanation too, the residual co2 in beer will be more if the beer was fermented and stored at let´s say 65F or 72F, the colder the fermentation, more residual co2 from fermentation in the beer.

 

[homebrewdad]

Creeping foam sounds like a bottle infection to me. 3.7 ounces in five gallons should never cause that kind of issue... and honestly, even overcarbed bottles (say, fermentation wasn't quite done when you bottled) shouldn't act that way. They should simply be way overpressured.

 

[Epiphanic]

It doesn't taste infected and it doesn't look infected, but that's something to consider. The pale ale was fermented at a cooler temperature than the saison so maybe I failed to account for the amount of residual CO2.

For what it's worth, I shared some of the pale ale with some friends and when he poured it, it poured incredibly nicely. That bottle has been the exception rather than the rule in that batch though.

 

[bleme]

I had the same thing happen with a Porter last year. My best guess is that fermentation stalled and bottling got it going again. FG was 2 points higher than predicted, which isn't terrible, but it could result in nearly twice the intended carbonation.