Gushers & Bombs

It's been a little while since my last post; although travelling and other obligations have prevented me from trying anything too wild brewwise recently. However, clearly my beer did not appreciate this and decided to scream for attention... in the form of a bomb.

My variation on a Rauchbier was the culprit. Every bottle of it I've opened has been a gusher; an overly carbonated beer that spills everywhere. It tastes great, but I typically lose about 65% of it to the foam overflow. See it in action below.

As much fun as this seems, I lose way too much beer and run other risks; so let's go over what's happening.

Most homebrewers I encounter typically keg their beer as it's easier and less time consuming. I've almost concluded I'm the only person that actually enjoys bottling. With a keg, you typically force CO2 into it to create carbonation. However, bottling works differently. Before you bottle, priming sugar is added to your batch. This acts as a small amount of additional fuel for the yeast to consume. As the yeast consumes sugar, pressure is created, just as with airlocks during normal fermentation. However, there's no escape for the gas and the pressure builds up creating carbonation.

Typically this is straight forward... until you hear a loud boom and find that a number of bottles have exploded leaving glass shard shrapnel scattered throughout the room. I'm quite glad I was not in the room at the time.

Some of the remnants of the bottle bomb

Due to every bottle gushing and their exploding siblings, something different is happening here. There's too much fermentation occurring inside the bottles. This typically means one of three things. If I added an excessive amount of priming sugar, this may be the result. However, I used the standard amount which I've used with every other beer, so this is probably not the reason.

This leaves two other possibilities. The first is that not all of the sugars were fermented. However, I let the beer in the fermenting bucket for about 6 weeks, which is more than enough time for ale yeast. It could have fallen asleep, but there is no specific reason why it would have. Something like a temperature change could cause that, but the temperature remained consistent. To conclude whether this was the cause, I could have measured the gravity of the beer before fermentation and before bottling. However, I neglected to do so... so too late now.

The third option: during the bottling process, the beer was unintentionally infected by something able to consume the sugars that the beer yeast isn't. Typically, this produces an off flavor; and this beer tasted great.

Hence I have no definitive conclusion, although it's one of the last two: infection or unfermented sugars. The good news is that I learned a lot from this experience. I'll be even more careful with sanitization, use a hydrometer (to measure gravity), and most importantly of all... keep any future gushing beers out of rooms where I spend a lot of time!