Foam from fermentation

[schismatic]

Hi guys,

Just started my first brew and am about 18 hours into the fermentation stage. I've noticed a fair bit of foam forming on top of my liquid, and I was wondering whether it was ok to leave it there or whether I should somehow remove it. I'm fermenting 5 gallons in a bin that's slightly bigger, and I estimate that at the moment I have about 5" of space for this foam above the liquid level. Is this enough?

Another question I'm keen to ask is about the lid of the fermentation bin. It's currently just resting on the top of the bucket to allow CO2 to escape, however will there come a point where I have to fully lock it down, or do i just rest it until fermentation is complete. I intend on transferring it all to a barrel eventually. How often should I be checking it and taking the top off the bin? I've read that it can be useful to stir it occasionally in the first few days so that yeast does not collect on the bottom. Is it a good idea just to leave it?

Thanks,

Tom

 

[Brewno]

Hi guys,

Just started my first brew and am about 18 hours into the fermentation stage. I've noticed a fair bit of foam forming on top of my liquid, and I was wondering whether it was ok to leave it there or whether I should somehow remove it. I'm fermenting 5 gallons in a bin that's slightly bigger, and I estimate that at the moment I have about 5" of space for this foam above the liquid level. Is this enough?

Another question I'm keen to ask is about the lid of the fermentation bin. It's currently just resting on the top of the bucket to allow CO2 to escape, however will there come a point where I have to fully lock it down, or do i just rest it until fermentation is complete. I intend on transferring it all to a barrel eventually. How often should I be checking it and taking the top off the bin? I've read that it can be useful to stir it occasionally in the first few days so that yeast does not collect on the bottom. Is it a good idea just to leave it?

Thanks,

Tom

The lid should be on tight from the moment you pitch your yeast and close up the bucket. An airlock should be used to let air escape. You shouldn't stir it either, it needs to be left alone to do it's thing. The foam (krausen) "is" the beer (wort) doing it's thing. That needs to form as the beer ferments and then it drops to the bottom as fermentation completes. If you have been stirring I hope you have been sanitizing your spoon.

Tommy

 

[simzy]

The foam is called krausen, it's a sign that fermentation is at its peak, and you'll be fine just to leave it on top of the brew. I don't think any off flavors will be detectable from leaving the krausen on the beer. After a couple days the krausen will subside.

If your bucket had a hole and rubber bung you could use an airlock. This would allow you to snap the lid completely shut, and not have to worry about taking it off to release pressure, and also will lower your chances of infection significantly since you won't have to keep opening your lid. I would recommend keeping the lid on as long as possible to minimize the chance for infection.

As for stiring the beer, I don't think I'd do that either. Once again, more opportunity for infection, and you could oxygenate the beer which would stall the attenuation process.

 

[schismatic]

ok cheers guys. my bin doesn't have a hole, and hence doesn't have an airlock. might it be a good idea to invest in one that does have one?

 

[david_42]

Airlocks are a very good idea.

 

[simzy]

yes, I would say it is almost a must.

 

[schismatic]

ah ok, well i will buy one for my next brew. i'm quite worried about this first batch now. i stirred it once this morning, and i don't think i sanitised the spoon before stirring it, although the previous day when sanitising the bin i stirred the cleaning solution thoroughly with the spoon but since then have just washed it in water and it was sitting in my living room overnight.... i'm also worried that i've let too much oxygen into the bin cause i've taken the lid off it about 4 times in the last 2 hours when i was checking it. i guess it's not a good idea to seal the bin completely if it's still making CO2, i don't need an explosion hehe. any suggestions on how best to go about brewing it with only a lid and no airlock on the bin??

 

[simzy]

I would seal the lid, then about every few hours crack it open just enough to let the air escape and seal it back up again. If you think you could get by with doing it less often then every few hours, I would.

Once your krausen subsides, I think you could get by with just cracking the lid once or twice a day.

 

[Yuri_Rage]

ah ok, well i will buy one for my next brew. i'm quite worried about this first batch now. i stirred it once this morning, and i don't think i sanitised the spoon before stirring it, although the previous day when sanitising the bin i stirred the cleaning solution thoroughly with the spoon but since then have just washed it in water and it was sitting in my living room overnight.... i'm also worried that i've let too much oxygen into the bin cause i've taken the lid off it about 4 times in the last 2 hours when i was checking it. i guess it's not a good idea to seal the bin completely if it's still making CO2, i don't need an explosion hehe. any suggestions on how best to go about brewing it with only a lid and no airlock on the bin??

Geez, leave your beer alone already!

Airborne bacteria can't "crawl" into your fermenter, rather, they settle like dust. Although an airlock is a great idea, as long as you just leave the lid loosely on top (and quit opening it up!), you don't face any serious risk of infection, especially if the fermentation is as active as you describe.

Avoid stirring the krausen back into the beer - it's normal and a sign of good fermentation...allow it to happen. Stirring, agitating, or otherwise messing with your fermenting beer should be avoided UNLESS you are using a highly flocculant yeast strain, in which case you could GENTLY rock the fermenter every few hours for the first few days of fermentation. In general, you want to keep oxygen (and your hands, spoons, sticks, etc...) out of your beer once fermentation has begun.

The bottom line:
RDWHAHB!!! ...and buy an airlock.

 

[Bobby_M]

I don't agree with sealing the lid without an airlock because any average to vigorous fermentation will blow the lid off within 15-30 minutes. Just lay the lid on and leave it alone. I would say though, that if you rack to a secondary vessel, you'll want an airlock. Drill a hole just big enough to jam a piece of hose into (tight fit). You put the other end in a beer bottle or jar half full of water or sanitizing solution, just below the waterline. DIY airlock.

 

[schismatic]

thanks guys, that's really cleared things up for me. have sealed it fully now and i'm going to relieve it every few hours - i have enough time to do this as i'm a student. i will invest in a bin with a hole for an airlock as well. another question - sorry! - but when it comes to finishing fermentation (about another 6 days according to the manufacturer's instructions on the extract's box), is it a good idea to try to avoid exposing it to the air as much as possible. i will have to have the lid off somehow as there is no bung-hole in my bin. i'll be syphoning it into a spherical barrel and then just keeping it in there. i don't intend on bottling it. is this a good way to go about things? how would you advise doing it in the future? (i hope to invest in a secondary bin soon).

 

[grnich]

I wouldn't bother with an airlock. Mine didn't come with one and I just rest it on the fermenter. CO2 is heavier than oxygen, so as the CO2 expands, it will push out the oxygen on the top first from under the lid.

 

[Evan!]

when it comes to finishing fermentation (about another 6 days according to the manufacturer's instructions on the extract's box), is it a good idea to try to avoid exposing it to the air as much as possible. i will have to have the lid off somehow as there is no bung-hole in my bin. i'll be syphoning it into a spherical barrel and then just keeping it in there.

'Spherical barrel'? Not sure what you mean. It's okay for the vessel to be open to the air while siphoning. The risk of contamination during that short time is very low. However, since this is your first batch, I want to stress the importance of NOT starting a siphon with your mouth. Your mouth is dirty, nasty, filled with lots of creatures that would LOVE to spoil your beer. If you don't know how to start a gravity siphon manually, please ask us, we'll give you the low-down.

But back to the "spherical barrel": what is it made of, and how are you planning on sealing it?

Also, you should not rely on the instructions of any box to tell you when fermentation is done...but 7 days is usually a good rule.

i don't intend on bottling it. is this a good way to go about things? how would you advise doing it in the future? (i hope to invest in a secondary bin soon).

If you don't bottle it, how are you going to carbonate it? It won't just magically carbonate by itself...you either have to force-carbonate it by putting it in cornelius kegs and installing a CO2 carbonating system...or you have to bottle it (in which you naturally carbonate it by boiling 3/4 cups corn sugar or 1-1/4 cups DME in a pint of water for 15 mins then cooled and mixed in with the wort just prior to bottling). Otherwise, your beer'll be as flat as Rachel Dratch.

 

[Evan!]

I wouldn't bother with an airlock. Mine didn't come with one and I just rest it on the fermenter. CO2 is heavier than oxygen, so as the CO2 expands, it will push out the oxygen on the top first from under the lid.

Better safe than sorry, especially when it gets to the secondary fermenter, and fermentation is pretty much done, so there's very little CO2 being pushed out.

I've always used airlocks. I mean, really, they cost a whopping $2 or something...

 

[schismatic]

i've nowhere to put an airlock unless i drill a hole - hence the investment in a better fermenting bin. the spherical barrel, let me clarify lol. it's basically a round, spherical barrel with a tap and 4 little legs to stand it somewhere. the cap at the top has a CO2 inlet and also a pressure relief valve. I'll give you a link to it - http://www.easybrew.co.uk/product_d...9c&PHPSESSID=a85075a75653697f9668b7340fadfd9c .
I was hoping I could carbonate the beer whilst it's in this barrel. I bought a kit, and with it came a bag of Young's Body Bru - http://www.easybrew.co.uk/product_d...9c&PHPSESSID=a85075a75653697f9668b7340fadfd9c (it's malto dextrin) - am i right in presuming that this is the corn sugar I can use to carbonate it? Could i just add it straight into my barrel?

 

[grnich]

Better safe than sorry, especially when it gets to the secondary fermenter, and fermentation is pretty much done, so there's very little CO2 being pushed out.

I've always used airlocks. I mean, really, they cost a whopping $2 or something...

I meant on primary only. Definitely use an airlock on the carboy...no other way to seal it really.

 

[casebrew]

Schizzy, read up at< http://www.howtobrew.com/section1/ > "The definitive book on making quality beers at home, available online in full text and graphics." Or at least it's a great on line resource.

Brewing beer isn't hard. Brewing a beer to exact expectations is. Welcome to the challenge.

 

[Yuri_Rage]

i've nowhere to put an airlock unless i drill a hole

So...drill a hole? Your total investment, should you choose to modify your lid for an airlock:

3-piece airlock: $1.05
Grommet: $0.35
Shipping: About $4.00

So for roughly $5.00 (less if you can get this stuff locally), you're all set.

Oh, and "burping" your fermenter is probably more detrimental than just setting the lid on top. The less you f$%^ with it, the better. Every time you mess with it to relieve pressure, you are potentially introducing contaminants. If you just set the lid on top and forget about it, you'll disturb the air around it less, thereby reducing your infection risk. Quit messing with your beer, RDWHAHB!

 

[undermind]

Otherwise, your beer'll be as flat as Rachel Dratch.

Dude, she's far from flat!