Reverse Working Air Lock

[Tucker]

Looking for some advice re a beer that I am making at the moment. Brew Craft Munich Lager, 100gms corn syrup, 300gms dextrose and 1 small red chilli (ment to make a crisp finish, I have been told. Not spicey).
The beer went in okey with some cold days I have used a heat belt 26degrees. Now I have noticed the air lock is trying to work in reverse. No bubbling out but lots of pressure pushing the water in the air lock back towards the brew. Any ideas. Have I killed my brew. No bad smells only been on for 4 days. Thanks

 

[floppinab]

Hi Tucker,
What did you do to the chilli prior to putting in??? Just popping it in whole probably won't have much impact, cutting open and deseeding would have made a bit more of a difference.

26 deg is probably a bit warm, generally speaking your Ale yeasts (which you would have used with this kit) like it best around 20 odd deg. Higher temps will produce more fruity flavours and potentially high order nastier tasting alcohols. You're beer will be fine but you might detect a little of these effects.

The only way you could be pulling air back into your brew is if you are bringing it the temp down from your ferment temps leading to some contraction in your fermenter as it cools, reducing the pressure in your fermenter and pulling air in from the outside.

 

[Chops]

Perhaps you've concocted some kind of homebrew blackhole that will soon crush the world as we know it?
I'd keep a close eye on it, those things are dangerous...

 

[Huhness]

Perhaps you've concocted some kind of homebrew blackhole that will soon crush the world as we know it?
I'd keep a close eye on it, those things are dangerous...

Yea i think i saw this in an episode of X-Files.. Didn't end well either.

 

[captian black beer]

If it's not fermenting then there's a fair chance that any change in air pressure and/or temp will cause it to suck in air. I wouldn't worry about it and just keep brewing. The only possible biological explination is that you've got nitrogen fixing bacteria in the brew sucking N2 out of the air. I highly doubt this considering they much prefer to live in soil as opposed to beer.

 

[Tucker]

Thanks for the advice. No I didn't cut up the chilli. I will try that next time. As for ending the universe can I take my brews that have worked with me. I will see when I bottle it all next week. The temperature has been going up and down. Thanks again.

 

[matti]

There are generally two reason why the airlock suck in rather then bubbles.
1. The temperature drops and the pressure decrease inside.
2. The yeast is growing and needs more oxygen and it sucking it in through airlock.

Nothing to worry about. In the future aerate the brew with a sterilized paddle or something similar.
This will help the yeast along faster.

The lagtime should be no more the 48 hour though.
Matti

 

[Trent]

There are generally two reason why the airlock suck in rather then bubbles.
1. The temperature drops and the pressure decrease inside.
2. The yeast is growing and needs more oxygen and it sucking it in through airlock.
Matti

Matti
Very sorry, but I couldn't let that second point go by without at least a question on it. To the very best of my knowledge, yeast use up the available O2 in the wort for their growth, and then turn to anaerobic activities like fermentation. Unless there is a biologist or someone else that has proof, I would have to say that yeast lack the ability to suck air from the atmosphere into the fermenter. I think that point number 1 is probably a little closer to the money. Also possible, as tucker tightened the lid on his fermenter he had somehow squeezed the fermenter with his knees, forcing some air out of it, and then the pressure difference sucked a little back in through the airlock?
Either way, I have been brewing for a couple of years now, and have never had air getting sucked back in through the airlock, even when I heavily underpitched. I am happy to be prved wrong (as I have no evidence, apart from what I have read about yeast), but IMO, felt that needed to be countered. I think that yeast just stop growing when there is no more O2 rather than look for more (I guess they are lazy like me!) Again, sorry, it is meant with no offence.
All the best
Trent

 

[KGB]

I agree with the above, the yeast wouldn't suck O2 into the fermenter. For a start it would need to displace whatever was in there (CO2 hopefully) first to create the space for more O2 to come in ie like lungs breathing in and out...

I'd bank on a temp change most likely. Keep it going at whatever temp you have it at now and see how it goes.
Did you measure the original gravity? Specific gravity readings will tell you whether its fermenting along or not.

If its still sucking in it might be an idea to drop a tiny bit of sanitiser into the airlock.