Fighting The Airlock ><

[sponge]

Or get rid of the lid all together and just use gladwrap...

 

[Jakechan]

I have to say Im surprised by all the santising and white glove treatment. I rip the lid off my fermenters daily for a big sniff of brewing goodness
So taking a sample for the hydrometer is nothing. Ive even stuck my finger in there and poked the dry-hopped flowers bobbing around the top after fermentation had ceased. Cant say Id recommend it but Ive had no problems.

Im also pretty relaxed with the sanitising of fermenters/hoses etc.

Cheers,
Jake

 

[dr K]

Oh ..the airlock..good for subs bad for brewing!
For such an unnecessary device the pain they have caused homebrewers makes them HB Enema No 1.
Strat easy, if your fermentor is not fully sealed they don't work anyway, so you wonder why your beer is not making those regular plooping sounds and think its not fermenting or worse think it has finished fermenting. Now in order to get that seal you need nice narrow grooves and tightly fitting tongues, not the easisest thing (the grooves) to clean and a wonderfull harbour for MR BUG, or you need rubber rings same thing just not as bad, not even to mention the evil that lies between the airlock grommet and the pails lid...brrrrrr
Anyway you overcome all of this, clean your grooves and grommets with religious fervour and create a sort of low pressure cooker, the CO2 builds to a certain level (as determined by the water in the airlock or PV) and hey bloop.
In the meantime the excess C02 under presure in your fermentor is (well its doing a lot of bad things to your beer) but it mainly means that proper fermentation is inhibited.
Toss it out, use as someone above suggested a bottle top instead.

K

 

[buttersd70]

Oh ..the airlock..good for subs bad for brewing!

Now thats the best line I've read in ages. :lol:

 

[TidalPete]

Glad that this topic has come up as I am gradually getting rid of my fermenters with taps below & changing over to the bucket-style fermenters (Cheaper) with the snaplock lid which are much better IMHO.
Had a bit of a think on how I would get my wort samples out for FG testing without lifting the lid & sprung onto the idea of taking off the top part of my two-piece airlocks, inserting an old sryinge, (Lengthened with a bit of plastic tubing) & taking the sample.
With all the Co2 lingering in the headspace there will be no hassles whatsoever.
Read "sanitised" where needed.

Shortly For Sale --- Lots of "Beneficial" fermenter taps.


TP :beer:

Do away with your airlocks...nothing but trouble & your yeast will thank you for it

All very well if you are not a greedy old sod who (Sometimes) fills up to the 26 litre mark & needs a blow off tube on occasion.

TP :beer:

 

[Ross]

All very well if you are not a greedy old sod who (Sometimes) fills up to the 26 litre mark & needs a blow off tube on occasion.

TP :beer:

Then use a blow off tube or sit your fermenter in a tray to catch the slops...

cheers Ross

 

[jonocarroll]

In the meantime the excess C02 under presure in your fermentor is (well its doing a lot of bad things to your beer) but it mainly means that proper fermentation is inhibited.

I'm going to question this one as a physicist. I'm not delving into the debate over the effectiveness of an airlock (17 brews and none of them failed to bubble correctly, no infections) but I do need to question your statement.

In an s-bend airlock, the pressure at any height is the same at all places. If the airlock is just about to bubble, then at the bottom of the s-bend is the gas-fluid interface, at which point they should both have the same pressure (same height). The pressure at the bottom of the fluid is the pressure at a depth of, say 1 cm = 0.01 m, above atmospheric. The gas should therefore have the same pressure;

p = density x g x h

p = pressure at a depth
density (water ) = 1000 kg/m³
g = gravitational acceleration = 9.8 ms^-2
h = height water is lifted = 0.01 m

so the additional pressure is p = 1000 x 9.8 x 0.01 = 98 kg m^-1 s^-2 = 98 Pascals at the bottom of the s-bend.

At the same height in the straight (gas) section, the gas should also be at this pressure. Below this, the gas will have a pressure of

p = density x g x h

So, say the additional headspace is 15 cm = 0.15 m and the density of CO₂ is 2 kg/m³ then the pressure at this depth will be

p = 2 x 9.8 x 0.15 = 3 Pascals

thus the total pressure at the top of the fermenting liquid is about 101 Pascals = 0.001 atmospheres.

This is why it's so easy to make an airlock bubble - a slight squeeze on the sides of the fermenter will do it.

Now for my question - The layer of CO₂ is never questioned as vital, even by those who swear by glad wrap, but as for it being 'under pressure' I hardly think it's a significant enough pressure to affect the beer in any way. Can you perhaps mention some of these 'bad things' that happen? Or perhaps how the fermentation is inhibited. Just looking at the numbers in curiosity.

 

[caleb]

So we should all just ditch the airlock and replace with a bottle cap or something?



:huh:

<_<

But why does every home brew kit ever from everyone always include it?

(and a bottle brush :lol: )

Does anyone have anything to say in defense of the humble airlock?


BTW I can draw a full tube of wort for hydrometer reading in much less than 15 minutes without bubbling the lock... and yes it is airtight otherwise. Nowdays I tend to just remove it if worried and then replace when done... first few brews I sucked a bit of water in before I learned.

 

[Jakechan]

I'm going to question this one as a physicist. I'm not delving into the debate over the effectiveness of an airlock (17 brews and none of them failed to bubble correctly, no infections) but I do need to question your statement.

In an s-bend airlock, the pressure at any height is the same at all places. If the airlock is just about to bubble, then at the bottom of the s-bend is the gas-fluid interface, at which point they should both have the same pressure (same height). The pressure at the bottom of the fluid is the pressure at a depth of, say 1 cm = 0.01 m, above atmospheric. The gas should therefore have the same pressure;

p = density x g x h

p = pressure at a depth
density (water ) = 1000 kg/m³
g = gravitational acceleration = 9.8 ms^-2
h = height water is lifted = 0.01 m

so the additional pressure is p = 1000 x 9.8 x 0.01 = 98 kg m^-1 s^-2 = 98 Pascals at the bottom of the s-bend.

At the same height in the straight (gas) section, the gas should also be at this pressure. Below this, the gas will have a pressure of

p = density x g x h

So, say the additional headspace is 15 cm = 0.15 m and the density of CO₂ is 2 kg/m³ then the pressure at this depth will be

p = 2 x 9.8 x 0.15 = 3 Pascals

thus the total pressure at the top of the fermenting liquid is about 101 Pascals = 0.001 atmospheres.

This is why it's so easy to make an airlock bubble - a slight squeeze on the sides of the fermenter will do it.

Now for my question - The layer of CO₂ is never questioned as vital, even by those who swear by glad wrap, but as for it being 'under pressure' I hardly think it's a significant enough pressure to affect the beer in any way. Can you perhaps mention some of these 'bad things' that happen? Or perhaps how the fermentation is inhibited. Just looking at the numbers in curiosity.

+1

 

[raven19]

I just put sanitiser in my airlock instead of water. If it sucks back through, it's just sucking clean sanitiser. At least that's the theory.

No worries so far.

Sounds like a plan.

Or get a refractometer, then you only ever need a few ml's to do a test. No problem with airlock moving much that way.

2c.

 

[pint of lager]

Decrease the amount of fluid in your airlock. That way, when there is negative pressure, it only draws air bubbles, rather than sanitiser or contaminated water into your brew.

I have seen discussion before about excess head pressure in fermenters causing problems in brews. This was on a commercial scale rather than homebrew scale and is often one reason touted for open ferments and union square style fermenters.

During fermentation, there are many yeast byproducts, not just carbon dioxide that come out of solution, as any avid airlock sniffer will tell you. An excess of headpressure means these volatiles are less likely to come out of solution and stay in your finished beer.

For the majority of brewers, an airlock style of brewing is prefferable. For those brewers seeking that extra 0.1%, an open system (during active fermentation) may just be what they need. Very experienced brewers talk about unwanted aromas and flavours being scrubbed out during fermentation. During active fermentation, your layer of krausen forms a protective blanket over your brew. (It will not protect against flying insects, dust, airborn spores and any other airborn nasties.) Once this krausen drops, your brew is open to oxygenation. There will be no protective layer. Oxygen at this stage will ruin your beer.

Think about the condensation on the lid, if there are volatiles, this condensation laden with volatiles will drop back into your brew. Just something for the brewers who lie awake at night wondering how to improve their brew. All new brewers, extract brewers and many ag brewers please ignore this and sleep well at night knowing that your brew under an airlock is perfectly fine. You must understand the risks of open fermenting before embarking on this method.

 

[staggalee]

Staggerlee,

I'm sure you can recall my posts trying to source 30 litre food-grade snap-top lid buckets with a threaded bung hole a short while ago? All your good advice was in vain as all I found were buckets under the 30 litre mark which are no good to me..
Gave up after an almost 18 months search & am now satisified to use the BrewCraft food-grade buckets (Snap-top lid, no threaded bunghole) which are cheaper anyway.
I already have the sryinges & the tubing so there is actually nil more effort involved in taking samples as per above as when I go through the tap with my remaining 30 litre threaded bung hole fermenters.
Using a Easy-Syphon may be a little slower when kegging but I can live with that.

TP :beer:

OK, I see what you were getting at now.
I thought you were persisting with 25l. pails with no tap, that`s why I couldn`t see how you would be any better off. {confusing isn`t it? }
But I regulary do 22l. brews in 25l. fermenters without probs, tho if using Nottingham just top up to 20l. to allow for its huge krausen.

stagga.

 

[WitWonder]

Or get rid of the lid all together and just use gladwrap...

x 2. No worrying about cleaning, sanitising, stuff getting sucked into the airlock, no taking it off for hydro readings, etc.

 

[jonocarroll]

See above...

<snip> Can you perhaps mention some of these 'bad things' that happen? Or perhaps how the fermentation is inhibited. Just looking at the numbers in curiosity.

I know, I know - bad form to bump your own stuff (you'll could go blind doing that ) but I'm intrigued now. Is there anything in this? I've never heard of problems like this before, and I'm willing to give dr K the benefit of the doubt for now.

 

[jonocarroll]

Getting less and less willing to give the benefit of the doubt. <_<

Seriously, anyone? I can't find a single bit of info to support this idea, but if it's true I'm very interested.

 

[BenH]

Perhaps this 'assertion' comes from the knowledge that dissolved CO2 in the beer inhibits yeast growth (in starters), as per Mr Malty

FWIW, I'm an airlock lover, and agree that the minimal increase in pressure would have a negligible impact on the volume of CO2 dissolved in the beer. Therefore, I don't think the airlock/no-airlock argument can be made on the grounds of 'pressure' or 'CO2'.

 

[mwd]

Airlocks came from the home winemaking brigade.

Back in the 70,s homebrewers in the U.K. used to put a clean cotton teatowel over the fermenter to keep nasties out.

But then it was illegal to home brew in Australia times change.

The pressure of CO2 in the fermenter sounds like codswallop to me as BenH states it takes bugger all to blip a S trap.