Continuing to carb in bottles? v. bottle explosion

[Bigsnake]

I just was going through my beer stash yesterday and realized I had a couple bottles explode! These are brews that were bottled roughly 4.5 Months ago and have been fine up to now.

I found all of them were the same batch (A steam beer). I found the rest of that batch and when I opened them they just immediately started foaming over. The last ones I had from that batch were a month ago and they were highly carbonated but didn't think they were slowly continuing to carbonate.

I ended up going through the rest of my bottles and opening a couple to see how carbonated they were and if they were getting anymore carbonated. I did find one other batch that was behaving similarly (an Oatmeal stout), but those are 8 ish months old and didn't blow up.

What is the cause of this slow carbonating? Is it normal? I store these bottles at room temp (house averages 70).

And don't worry... the ones that I opened that were fine I ended up drinking. My fiance' came home from work to find me passed out in the main room.

 

[ifishsum]

It's possible that it was a couple of points away from being finished when it was bottled, or maybe slightly overprimed. Once it's bottled, there should only be so much sugar for the yeast to eat, so barring an infection of some sort it should not continue to carbonate to the point of bottle bombs, regardless of time. Once the available sugar is eaten up they can't go any further.

Were there any slow fermenting type of sugars in the batch, honey maybe?

 

[david_42]

Right, most of the time continuing fermentation is due to early bottling. Infection is another possibility, but if the beer tastes OK, then you can rule it out.

 

[Edcculus]

It might not be a bad idea to stash them all in the fridge. That will stop any more explosions and might help stop the gushers.

 

[Bigsnake]

It's possible that it was a couple of points away from being finished when it was bottled, or maybe slightly overprimed. Once it's bottled, there should only be so much sugar for the yeast to eat, so barring an infection of some sort it should not continue to carbonate to the point of bottle bombs, regardless of time. Once the available sugar is eaten up they can't go any further.

Were there any slow fermenting type of sugars in the batch, honey maybe?

No honey or added sugars in this batch. It was all-grain.

I just find it strange that it took so long for it to get to this point of exploding.

I also don't think it was over primed as I used one of the 4.5 oz packets of priming sugar from AHS.