Air Lock vs. Blow Off Tube

[dragonlor20]

It all depends on your primary fermentation vessel.
If I ferment in a carboy I tend to use a blow off tube.
If I ferment in my Stainless stell conical, I use an airlock
If I ferment in my 17.5 gallon bucket, I don't use either, and go with the open fermentation method.

It really depends on your setup.

That's a really big bucket.

 

[Glibbidy]

It' large and in charge. Note it's vessel under the two six gallon pails.

 

[lodgeskins]

Papazian writes, (a blowoff tube) "will expel excess yeast, excessively bitter hop resins, and a small amount of fermenting beer; a small price to pay for a smooth, clean-tasting homebrew". He also states that the blowoff method allows "other things that may contribute to hangovers when consumed" to be expelled.
What do some of the experienced brewers here think? I've only used an airlock but I'm wondering if there's a better brew to be had through using a blowoff. Or, is this notion dated (as a previous poster wondered)?

 

[Surfrider]

Sorry to bump a semi-old thread, but I am very interested in this topic, and would love to hear answers to Lodgeskins' question (the reply immediately above this one) from some of the more experienced members, if they'd be so kind.

Thanks.

 

[Schnitzengiggle]

Blow-off for the first few days and then the airlock, I am not going to chance having to mop the ceiling, it looks like a real pain in the ass!

 

[SpanishCastleAle]

Papazian writes, (a blowoff tube) "will expel excess yeast, excessively bitter hop resins, and a small amount of fermenting beer; a small price to pay for a smooth, clean-tasting homebrew". He also states that the blowoff method allows "other things that may contribute to hangovers when consumed" to be expelled.
What do some of the experienced brewers here think? I've only used an airlock but I'm wondering if there's a better brew to be had through using a blowoff. Or, is this notion dated (as a previous poster wondered)?

I read that very early in my brewing 'career' and so that's what I always thought. Every one of my early beers had a blowoff...by design. Then I came here and was told that I was losing head-positive compounds and that blowoffs were 'bad'...which I still doubt to some degree but this advice was coming from experienced brewers so I stopped 'designing in' blowoffs.

I need to do some experimenting...some of my blowoffs beers have the best head evar and some of my non-blowoff beers don't...I see no correlation between head retention and blowoffs but I haven't really 'tested' it.

EDIT: Oh and FWIW, I use a blowoff tube in the beginning 'just in case' and then switch to an airlock after the 3rd-4th day or so. That way I can indeed do the 'relax' part of Relax, Don't Worry...

 

[ClaudiusB]

I read that very early in my brewing 'career' and so that's what I always thought. Every one of my early beers had a blowoff...by design.

Same here.

Then I came here and was told that I was losing head-positive compounds and that blowoffs were 'bad'...which I still doubt to some degree but this advice was coming from experienced brewers so I stopped 'designing in' blowoffs.

My brewing practices are copied from the commercial brewers, no airlocks.

Cheers,
ClaudiusB

 

[grape-soda]

I have a couple of questions:

1) Do you always need to use sanitized solution in the water where the blow tube blows into?

2) I just had an airlock disaster overnight. It blew off and sprayed yeast vomit everywhere. This beer has a 1.074 OG. Should I have used a blow off tube from the start?

 

[Kauai_Kahuna]

Every beer I make I start with a blowoff tube, and I use idophor or starstan sanitizer in a 2 qt bottle filled around 1/3 of the way. Always!
I just reuse what I used to sanitize the primary.
Once the krausen has fallen I throw on an air lock just to make it easier to deal with. And after too much time the sanitizer in blowoff container will go inert.
Moving a 6.5 gal carboy with an blowoff tube and 2 qt container is a pain, so air locks are best for longer term ageing.

 

[SugarBear]

I had an explosion earlier tonight, while using a blow-off. It wasn't disastrous because I keep my carboy in a large rubber-maid container. There was some cascade on the ceiling though. I had a fantastic cold break, and was at around 80F within 5 mins, so I know pitching temp was not an issue. The temp in here is just under 70F, so I doubt that was a major contributor either. I've never had anything like this happen, and I've made a lot of beer over the years.

This time however, I used a different yeast (Safbrew S-33) and spring water.
I'm wondering if the yeast was able to start the party early due to the lack of tap water baddies this time around. ie: very little resistance in the fermentor.

Someone earlier in the thread mentioned that they dremeled off the plastic strainer on the bottom of the lock. This move probably would have saved me a bit of a mess, since the foam flow was just too much for the lock to handle. Consequently this all happened within 3 hrs from pitching. It normally takes at least 24 hrs for my brews to take off.

For now, I'm letting the carboy vent all it needs to. I'll cap it up later....

 

[milltyl]

I'm a first time brewer, I was glad to find this thread.

I have a Caribou Slobber (Northern Brewer) in my primary fermenter which is a 6.5 gal glass carboy. 10 hrs after putting it in the fermenter my airlock is bubbling like crazy.

I'm worried about blowing the bung out of the carboy and making a mess. Should I preemptively put a blow-off tube on it?

Also, what makes a more fast/active fermentation?

Thanks!

 

[ThreeTaps]

A blowoff tube is great for when you have a really active fermentation, and the krausen (foamy build-up on top of the beer) builds up to a volume that surpasses the empty space in your carboy. Having a tube attached to your airlock stem then allows the excess krausen to travel into a bucket that is filled with sanitized water (make sure it's sanitized so nothing bad can travel back up through the tube). In most cases that I've found, an airlock is fine, however in my most recent all grain batches I've needed a blow off tube. If your airlock is only bubbling, and no krausen is rising into the airlock stem, then that itself is not going to blow your bung off.

Active and fast fermentation is a result of proper pitching temperature, as well as pitching rate, as well as an overall good environment for the yeast to divide. If you pitch your yeast in wort that's too hot, it will reproduce much quicker and create off tastes and stuff. Also, the viability of your yeast (basically the health of it) will make a big difference. Yeast is a HUGE part of good beer, so it's important to treat it as such. I always re-hydrate my dry yeast, and make starters with liquid yeast. Just make sure you pitch your yeast at the proper temperature, aerate the wort well (yeast can live and grow with OR without air, however it's better when the wort is well aerated) and keep the fermenting wort in a nice cool environment. Try to keep the temperature of the wort no higher than 74F at all times, especially during the first few days. If it gets up higher than that during active fermentation (which usually lasts 2-3 days, depending on your yeast and fermentable sugars in the wort) it can produce esters that give off flavors (such as banana...I've done that before) in your beer.

If you need advice or tips on any process or step, or just overall stuff, let me know. I've put just under 450 posts on this forum in exactly 2 months today, the majority of which were extracting information from the pros here

 

[MBasile]

I learned the hard way to do a blow off for higher gravity brews (learned with a 1.06x stout). My IPA was in the 1.05's so I did a blow off tube and was glad I did. My latest stout (1.050) I threw it on and once again was glad I did. Once the krausen went down then I swapped it out for an airlock because I don't like transporting the carboy with the tube hanging off, it's too awkward.

 

[Hodor_Baggins]

Wow a six page thread about air locks and blow off tubes and no one has mentioned aluminum foil yet???
For the most part that's what I use when I use carboys, just sanitize some aluminum foil and form it over the opening of the carboy. It lets blowoff escape without an explosion (but it can still create a bit of a mess) and no worries about suckback!

 

[milltyl]

Thanks for the information! and fast too! The Krausen is not up to the airlock, although it's "grown" to about 2 inches. I'll keep a good eye on it and add the blow off tube if necessary. My O.G. was 1.052 and I'm using a satellite bottle to take additional hydrometer readings.

 

[ThreeTaps]

Thanks for the information! and fast too! The Krausen is not up to the airlock, although it's "grown" to about 2 inches. I'll keep a good eye on it and add the blow off tube if necessary. My O.G. was 1.052 and I'm using a satellite bottle to take additional hydrometer readings.

Did you get that satellite bottle advice from homebrewers.com? Well, don't do it. The wort/beer in your satellite bottle needs to have -exactly- the same amount of fermentable sugars in it as your filled carboy, and chances are it's not going to ferment at the same rate, even though they say it "does". My first brew I used one too, just to see how accurate it was, and it wasn't. My satellite was a good few points off from the real beer when taking the FG reading.

Remember, your beer is much more resilient than you may think. Opening the top and taking a sample out via turkey baster or wine thief (sanitized, of course) isn't bad. You have a big pocket of C02 at the top, which no bacteria will be able to live through for such a short amount of time.

Always take your readings from your real beer.

 

[milltyl]

No I actually got the tip for satellite hydro readings from a website with videos (http://www.homebrewingvideo.com/category/how-to-brew/). My kit came with a beer thief so I'll probably do what you mentioned. Take readings from both and see how they compare.

I have another question too. My kit did not come with a priming sugar for bottling. Do all beers require the primer sugar or just beers that need bottle conditioning?

Thanks again.

 

[ThreeTaps]

No I actually got the tip for satellite hydro readings from a website with videos (http://www.homebrewingvideo.com/category/how-to-brew/). My kit came with a beer thief so I'll probably do what you mentioned. Take readings from both and see how they compare.

I have another question too. My kit did not come with a priming sugar for bottling. Do all beers require the primer sugar or just beers that need bottle conditioning?

Thanks again.

That site is the instructional video site for homebrewers.com.

Yes, you will need dextrose (corn sugar) for every batch at bottling stage. Are you sure you didn't put it in the boil? You will need 1/2lb for every 5 gallons of beer. The sugar is what creates carbonation.

 

[milltyl]

That site is the instructional video site for homebrewers.com.

Yes, you will need dextrose (corn sugar) for every batch at bottling stage. Are you sure you didn't put it in the boil? You will need 1/2lb for every 5 gallons of beer. The sugar is what creates carbonation.

Hmm... I hope I didn't put it in the boil. Would it matter though? Just more for the yeasty boys to munch on...

I'm ordering some sugar now. Do the expenses ever stop?

 

[MBasile]

Hmm... I hope I didn't put it in the boil. Would it matter though? Just more for the yeasty boys to munch on...

I'm ordering some sugar now. Do the expenses ever stop?

Only if you stop brewing! But why would anyone do that?

 

[Tiako]

I have a 3 part air lock and it went all up into that. I don't know how bad because I was on vaction. The top is still on it so it must not have been that bad. However, my carboy is 100% full. Should I just leave it as is or what>?

 

[Tiako]

Oh never mind I thought it was full but the krausen dried to the inside of the carboy.

 

[Lumberg1]

Famous last words.... before the ceiling staining explosion.

I said the same thing! "I've never needed a blow off tube so an airlock will be fine." Well wouldn't you know, I came home from work today to find my air lock completely full and flowing off the sides. I quickly found some extra hose I had laying around made up a batch of star-san and got it ready to go on the carboy and right when I touched the airlock it popped off and sprayed everywhere! I guess that's what I get for thinking I'd never need one. Blow off tubes for primary from now on!

 

[Bruin]

After today, blow off tube right from the get go. No need to change to an airlock, won't be moving Better Bottle around once I set up blow off tube. I was checking out the steel fermenters in my local brewpub. Big ass hose coming off the top into a a bucket of sanitizer. The perfect airlock, why mess with anything else.

 

[rellot]

Lately I've been using the bottom piece of a three piece airlock and then a foam stopper stuffed in the top.

My thought is during primary it is better for fermentation to have access to oxygen, but don't want any bugs getting in. So its basically the same as open fermentation. I don't use a regular airlock until secondary, which I do with corny kegs.

Although I wonder if allowing the krausen to escape out might cut down on the type of things Papazian speaks of. I've never done the same recipe both ways to see if there is any taste difference.

Papazian writes, (a blowoff tube) "will expel excess yeast, excessively bitter hop resins, and a small amount of fermenting beer; a small price to pay for a smooth, clean-tasting homebrew". He also states that the blowoff method allows "other things that may contribute to hangovers when consumed" to be expelled.

Although since my primary is a 7.5 gallon pony keg, for 5 gallons, that's plenty of head space. To have a blow off tube I would have to go back to carboys.

Does anyone know what commercial breweries do? Do they do open air fermentation? Do they take of the krausen or let it fall back in?

 

[SkyHighBrew88]

Here's a pic of the second beer I ever made. It was an Oberon clone that used Wyeast 1010 (always goes nuts). Notice the domed lid of the bucket. Seconds from disaster haha.



Beer ended up good, but back then I didn't know any better.

 

[aerod1]

I never use an airlock anymore. I have gone strictly to blow off tubes. Seems to work great with less worry. Of course I ferment on the cold side which is slower anyway.

 

[day_trippr]

[...]
Does anyone know what commercial breweries do? Do they do open air fermentation? Do they take of the krausen or let it fall back in?

I believe the predominant mode of operation at most breweries is to use very large temperature controlled conical fermenters that are closed at the top. Hence removing krausen isn't happening there - no way to get to it.

From everything I've read in the last few years, open fermenting is going the way of the dinosaurs...

Cheers!

 

[Waunabeer]

Here's a pic of the second beer I ever made. It was an Oberon clone that used Wyeast 1010 (always goes nuts). Notice the domed lid of the bucket. Seconds from disaster haha.

View attachment 32191

Beer ended up good, but back then I didn't know any better.

Well then what the hell am I doing wrong? I've made oberon clones and many other types of beer and have never had an ounce of krausen in my bubbler. My beers come out good, but why would my fermentation be so tame compared to what I'm seeing on here? I use the standard plastic bucket for the fermenter and usually fill it with 5.25 gal. and have never come close to an overflow.

Should I be worried?

 

[SkyHighBrew88]

Well then what the hell am I doing wrong? I've made oberon clones and many other types of beer and have never had an ounce of krausen in my bubbler. My beers come out good, but why would my fermentation be so tame compared to what I'm seeing on here? I use the standard plastic bucket for the fermenter and usually fill it with 5.25 gal. and have never come close to an overflow.

Should I be worried?

Well I should mention that my temperature control system is nothing more than cranking on the A/C to 68F (bout as low as SWMBO can stand). Do you have something that allows your fermentation temps to remain lower? That could be why. Otherwise I'd attribute the crazy krausen to Wyeast 1010, the fact that my OG was in the low 1.060s, and the lack of proper temp control. Frankly, i'm not sure I'll ever do a wheat using 1010 again in a bucket. I've got a 6.5 gallon that gives much more headspace now.

Also interesting to mention that I have done a NB Sunshine Wheat clone with WY1010 and the krausen on that one was pretty large & in charge as well.

 

[Waunabeer]

I do have a fermentation chamber that I keep constant temps with. Is that the main reason why my fermentation is more tame?