Fermenting Through Airlock

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Leemond

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Hi all,

Woke up this morning to find my beer frothing through the airlock on top of my demijohn! The bubbling is still frequent but quite small however there is a Lot of activity in the demijohn itself. It's also at 24 degrees when it's normally significantly lower than that. I've therefore a couple of questions if anyone could help me out please...

Is the increased temperature due to the level of fermentation going on?

Could it be due to over pitching yeast? I have trouble measuring out of the sachets as I only do 4L batches and the sachets are for much larger brews.

Will any of the mild sanitiser liquid I have in the airlock have got into the beer now?

Any advice appreciated!

Cheers

Leemond
 
Vigorous fermentation does increase temperature yes and it can be quite a significant increase. What is the ambient temp where the brew is stored?

It could have although I don't think it'd be too likely, was it a no rinse sanitiser? I think you'll be fine, just clean up the air lock and try and get the temp down if you can.

What was the brew? I find darker beers, especially any with lactose, ferment much more vigorously.
 
Agree with DoctorMick, but if you haven't swapped out the air lock you need to do so. I would also recommend rigging up a blow off tube in the future.

A blow off tube replaces the airlock assembly and the other end of the tubing is placed in a container of sanitizer next to your fermenter.


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Yep a blow off tube is the way to go. I find that my PVC syphon hose fits perfectly into the grommet in the FV lid, then just put the other end in a jug of starsan.I always do this if expecting a vigorous fermentation or if there's a small headspace because this happened once too often:
 
Thanks for the replies guys. To answer some of the questions...

It's a light ale brew (pale/golden promise malt) however the Yeast (Safale S-04) did suggest high sediment and fast fermentation.

The temp in the room is around 19 degrees but yesterday it was up to around 24 on the demijohn thermometer (now around 22) - the activity has subsided slightly but the newly replaced (sanitised) air lock is still mildly bubbling once a second or so.

The thing is I've been covering the demijohn to keep light off it following concerns in my last brew with sediment appearing to stick on the sides of it during fermentation. I expect this will be contributing to the higher temperature but I don't want light getting at it so a bit stuck between a rock and a hard place with that one. All that said, the yeast did say it will work between 12 & 25 degrees (ideally the middle of the range) so hopefully all will be well?

I've never had it bubble over before so the airlock has always been sufficient but will take the advice on board regarding the additional tubing.

Huge thanks again for all the advice - already finding this to be a great little forum, hopefully I can repay with some of my own experiences down the line :thumb:
 
Does this effect on the beer when this happens? I'm fermenting a pale ale just now and it's gone crazy! I'm getting loads of foam through the blow-off tube, which I've cleaned out once already but it's frothed up yet again. Is it safe to just let it do it's thing until primary is done? It's a 4.5L batch using Ireks Pale Ale and Munich malt with US-05 fermenting at 19C, OG1.060.
 
Does this effect on the beer when this happens? I'm fermenting a pale ale just now and it's gone crazy! I'm getting loads of foam through the blow-off tube, which I've cleaned out once already but it's frothed up yet again. Is it safe to just let it do it's thing until primary is done? It's a 4.5L batch using Ireks Pale Ale and Munich malt with US-05 fermenting at 19C, OG1.060.

If you're using a blow off tube you should be fine. If you're using an airlock there is a risk that some of the overflowed wort could be sucked back in to the FV and could take potential nasties back in with it.
 
Bottling this batch this evening! Need to invest in a better, more hygienic siphon for my next batch though :doh: - that said, my brews have all been ok so far but best to be safe in future!
 
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