I brewed a batch of extract, (German Alt) in March. I set up a blow off tube and had very active fermentation for the first few days. I then let it sit for 2 months. Today when prepping to bottle the batch, I found a layer of mold on the surface of my water trap for the blow off tube. The bottom of the tube was still below the surface. I found no “off” odors, nothing funky. I went ahead and bottled the batch.
Do you think this is a problem?
I usually rack to a secondary after 2 weeks but did not on this batch.
I also never replaced the blow-off tube with a bubbler.
Any advice/opinions are appreciated.
The end of the hose being under the mold on the surface probably protected your beer. The blow off hose and the container you used will need a good cleaning though.
Starsan solution in the blow off container will prevent the growth of mold.
Normally you would switch the blow off tube to a regular bubbler after the violent fermentation ends. We all have life that gets in the way of brewing so I’m the first to admit I have forgotten steps that have and have not affected my beer.
Given the size of a blow off tube, the distance the end would be form the fermenter and the alcohol content of the beer, I wouldn’t worry about it.
Many of us use cheap vodka in our air locks but with the size of the container with a blow off I use sanitizer solution. It is unlikely it could be sucked back with the size of the tube.
I did use sanitizer in the water trap but I had a good layer of foam from the fermentation. I assume this gave the mold a place to grow. All is cleaned up. I am disposing the blow off tube to be safe.
