I just brewed an Irish red. Pitched the yeast in the high 60s and then put the bucket in my ferm fridge at 65. I went down an hour later to clean up a little and I could see star san being sucked from the airlock. I'm not worried about it because it was a little amount and it is a sanitizer. I'm just curious as to why it happens. Anyone know? Different pressures or swing in temp?
Star San from airlock is being sucked into bucket...why?
- Thread starter h22lude
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When the temperature inside the fermenter lowers, it does that. It pulls a vacuum. You must have pitched warmer than the current temperature, and as it cools it contracts.
I've really seen this happen with cold crashing! To go from 68 degrees to 32 degrees will really do it. When I cold crash in a fermenter, I take off the airlock and put some sanitized foil on it, just so it doesn't suck back all of the airlock liquid.
Wanted to ride along on this thread. I have a similar situation but am a little more concerned. Quick overview of my setup:
- 6 gal better bottle with 5 gallons of fermented beer in it
- approx 3 to 3.5 feet of tubing going from the stopper to a plastic cup filled with star san (my standard blow off rig)
- Beer has been in the fermenter for just shy of 3 weeks (active ferment was complete inside of a week)
- Just to add some intrigue, since Yoop is on this thread, the beer in question is your Fizzy Yellow Beer
I had been slowly ramping the temps down over the last 3 or 4 days with the expectation of kegging today. Last night the beer was at 50F and the fermenter showed no signs of cavitation, so I went ahead and turned the temp down to 35F.
Got up a little bit ago, checked on the beer only to find the sides of the better bottle sucked in and starsan in the tubing. I can't be entirely sure, but based on what I remember being in the cup, an ounce, no more than 2.5 ounces of star san looks like it went into the fermenter.
I pulled the tube from the stopper end to let the better bottle expand. I figured I pulled in a little air but am not so worried about that since this beer is going in the keg and on the gas in a few hours.
I calculated (and even estimated high) the percentage of starsan that likely went into the beer. Even at 3 ounces, I come up with .4% in a 5 gallon batch. Knowing that starsan becomes inert at low pH, I am not worried about the amount star san as much as I am concerned that an open cup of star san in my fermenting fridge might have started to pick up some bugs over the course of 3 weeks.
This is going into a keg and straight into my keezer, so it's not like I am going to feed it any more maltose or dextrose by naturally carbing. And with football season in full swing, this batch won't hang around long. My numbers indicate about 4.8-ish ABV, plus around 20 IBU. Will that, plus the cold temps be enough to suppress anything that might have come in with the star san?
- 6 gal better bottle with 5 gallons of fermented beer in it
- approx 3 to 3.5 feet of tubing going from the stopper to a plastic cup filled with star san (my standard blow off rig)
- Beer has been in the fermenter for just shy of 3 weeks (active ferment was complete inside of a week)
- Just to add some intrigue, since Yoop is on this thread, the beer in question is your Fizzy Yellow Beer
I had been slowly ramping the temps down over the last 3 or 4 days with the expectation of kegging today. Last night the beer was at 50F and the fermenter showed no signs of cavitation, so I went ahead and turned the temp down to 35F.
Got up a little bit ago, checked on the beer only to find the sides of the better bottle sucked in and starsan in the tubing. I can't be entirely sure, but based on what I remember being in the cup, an ounce, no more than 2.5 ounces of star san looks like it went into the fermenter.
I pulled the tube from the stopper end to let the better bottle expand. I figured I pulled in a little air but am not so worried about that since this beer is going in the keg and on the gas in a few hours.
I calculated (and even estimated high) the percentage of starsan that likely went into the beer. Even at 3 ounces, I come up with .4% in a 5 gallon batch. Knowing that starsan becomes inert at low pH, I am not worried about the amount star san as much as I am concerned that an open cup of star san in my fermenting fridge might have started to pick up some bugs over the course of 3 weeks.
This is going into a keg and straight into my keezer, so it's not like I am going to feed it any more maltose or dextrose by naturally carbing. And with football season in full swing, this batch won't hang around long. My numbers indicate about 4.8-ish ABV, plus around 20 IBU. Will that, plus the cold temps be enough to suppress anything that might have come in with the star san?
