Why You Need a Blowoff Tube
Last weekend, I brewed a new batch of beer using the Vermont IPA yeast strain from our friends at GigaYeast. We first connected with these guys during SF Beer Week, and they gave us a few samples to try when they stopped by for our open house. Local yeast goes great with local beer.
As the package promised, the GigaYeast kicked fermentation off to a fast and strong start. I let the yeast to do its magic and, within a few hours, there was a lot of activity in the primary fermenter. I thought to myself, “This is why you need a blowoff tube!”
I can’t tell you how many times, in my early days of homebrewing, I wiped exploded beer off the walls of my closet after neglecting to install a blowoff tube during the fermentation process. Technically, you don’t always need a blowoff tube, but we never leave it to chance.
Here are a few guidelines for using blowoff tubes:
- Replace your Airlock with a blowoff tube. A blowoff tube is a sanitary way of releasing excess foam (Kräusen) and CO2 pressure during fermentation.
- If you don't want to go through the trouble of installing a blowoff tube every time you brew, make sure to use one when trying a new yeast, brewing a high-gravity beer, or your fermenter is full to the top in the primary.
- Be sure to leave a decent amount of head space (volume and distance between the level of your beer and the top of your fermenter).
- Make sure to submerge the free end of the blowoff tube in a jar or bottle of water, and use sanitized water in your blowoff tank.
- The reality is that blowoff tubes aren't always necessary, and needing one depends on several factors. For us, it has become ritual, only because we’ve had way too many beers explode in the closet to risk having to clean that mess up again. If you’re unsure if you need one, just do it. Better safe than sorry.