Last night I was trying to relax after a rough day at the office. I was startled by a loud pop that almost sounded like an explosion. It turns out a bottle of leftover Pennant Race Pumpkin Wheat blew up worse than Clay Buchholz blew up on the mound.
This is aptly called a bottle bomb. It is the worst case scenario when you bottle condition, or naturally carbonate your beer inside the bottle. Luckily my bottle bomb from last night was contained inside a 12-pack box located on a landing. All in all it was like a Wade Miley start, scary but mercifully quick. The last time I had a bottle bomb I woke up and went to the kitchen to make some coffee. I saw a bottle cap facing me on the floor. Then I saw it was still attached to the neck of a bottle which was almost as confusing as what happened to Justin Masterson’s fastball velocity. More unusual was that the rest of the bottle was nowhere to be seen, until I figured out what had happened. I was lucky that time that I noticed the debris from the bottle bomb before walking into the kitchen in bare feet.
Usually before a bottle of beer becomes a bottle bomb, it will be a gusher first. If a beer is a gusher the beer will gush out of the bottle as soon as you pop the cap. After one of the bottles exploded last night, I dumped the rest of the beers in the box. Here is video of the beer gushing as I popped the top. A best practice is to pop the top ever-so-slightly to bleed the pressure so you don’t have beer spraying all over the place like Joe Kelly’s fastball.
Bottle bombs and gushers can be caused by several different factors. If you bottle your beer before fermentation is complete, the additional CO2 is trapped in the bottle and the pressure will build. Adding too much priming sugar on bottling day will yield similar results as your beer explodes out of the bottle faster than a Rick Porcello gopher-ball leaves the park. That is why it is critical to wait until fermentation is complete before packaging your beer. I strongly recommend a priming sugar calculator to make sure you use the proper amount of priming sugar.
The beer was only a small batch. The box in question was misplaced until I found it in the middle of December. I did enjoy a few of these before last night even though I never did write a tasting notes post. At that time the carbonation level of the beer didn’t seem off which makes me think neither of the problems above were what caused the bombs and gushers. Remember, when brewing sanitation is godliness.
The fact that this didn’t blow up until now makes me think it was a contaminant that got into the beer. Whatever it was acted slowly. The pressure inside the bottle built up slowly until one of the bottles finally went boom.