what is the point of an airlock if you can

[Beginner_at_Work]

I heard you can just put on the cap of a bottle on loosely so the co2 can escape and oxygen wont get in. ..... so if its that simple then whats the reason for an airlock? or even those who use condoms?

 

[RM-MN]

Um, do you ever get fruit flies in your house? They don't swim so good through the liquid of an airlock but they might crawl under the loose cap to get at that sweet smelling wort.

Most of the time I could get by with just that loose cap but I don't want to risk a batch of beer to a stupid little fruit fly with way too much curiosity.

 

[LLBeanJ]

An airlock in primary isn't absolutely necessary due to CO2 being produced and creating positive pressure inside the vessel. If you use a secondary or plan on leaving the beer in primary for an extended time, you should use an airlock once active fermentation has stopped. If you live in an area that is susceptible to fruit flies or other pests, I recommend that you seal up your fermenter tight and definitely use an airlock.

I've not used an airlock for primary for past couple of years, as I've been using the airlock hole/grommet in my bucket lid for a thermowell. No issues in what must be close to 50 batches doing it that way. I also don't snap the bucket lid down, just let gravity hold it on. However, I should mention that I do ferment in a chest freezer ferm chamber, so the fermenter is not normally exposed to environmental variations. YMMV.

 

[Beginner_at_Work]

loosen the cap on a bottle for it to ferment, that is what i heard from comments...... so yeah whats the point of using an airlock in that case.

EDIT: sorry i asked this in another beer forum on this site, but thats because i thought my original post was deleted, but now i find it. i apologize

 

[Beginner_at_Work]

Um, do you ever get fruit flies in your house? They don't swim so good through the liquid of an airlock but they might crawl under the loose cap to get at that sweet smelling wort.

Most of the time I could get by with just that loose cap but I don't want to risk a batch of beer to a stupid little fruit fly with way too much curiosity.

thank you the exact answer i was looking for.

 

[Gavin C]

Fermentation in individual bottles is not done in most instances. There are some exceptions to this statement which are beyond the scope of the thread.

No one to the best of my knowledge advocates airlock placement on bottled beer/wine/cider/hooch. The airlock's pupose is to vent formed gases (CO2) and prevent ingress of O2, microbes and particulate from the environment surrounding the fermentation vessel.

I think you may have got your wires crossed or perhaps I am misunderstanding you.

 

[Beginner_at_Work]

An airlock in primary isn't absolutely necessary due to CO2 being produced and creating positive pressure inside the vessel. If you use a secondary or plan on leaving the beer in primary for an extended time, you should use an airlock once active fermentation has stopped. If you live in an area that is susceptible to fruit flies or other pests, I recommend that you seal up your fermenter tight and definitely use an airlock.

I've not used an airlock for primary for past couple of years, as I've been using the airlock hole/grommet in my bucket lid for a thermowell. No issues in what must be close to 50 batches doing it that way. I also don't snap the bucket lid down, just let gravity hold it on. However, I should mention that I do ferment in a chest freezer ferm chamber, so the fermenter is not normally exposed to environmental variations. YMMV.

thank you again, the answer i was looking for

 

[doug293cz]

loosen the cap on a bottle for it to ferment, that is what i heard from comments...... so yeah whats the point of using an airlock in that case.

Fermentation can get very vigorous, even violent. With an active enough fermentation, the krausen could clog up the bottle cap, and the bottle could explode. An airlock in a stopper or gasket will typically blow out of the fermenter if things get too wild. This can make a huge mess, but at least the fermenter doesn't explode. Many people rig a blow off tube instead of using a simple airlock. The blow off will handle a lot more foaming krausen, without creating a mess.

Brew on

 

[Conan]

Fermentation can get very vigorous, even violent. With an active enough fermentation, the krausen could clog up the bottle cap, and the bottle could explode. An airlock in a stopper or gasket will typically blow out of the fermenter if things get too wild..

Brew on

Not to contradict, but every once in awhile that airlock will stick in the gasket and blow the lid off a bucket and the gasket out of the lid. It may also lift the lid off a fermentation chamber, all at 62°F.

Which is why the rest of your statement, about using a blowoff tube, is incredibly accurate.

Fermenting in glass (bottles, carboy, growler) can be a bad idea if something does clog and doesn't give. This is primarily dangerous if trying to bottle condition/ naturally carbonate in growlers, which aren't designed to handle pressure.

Since we all seem to be a little lost, what kind of bottle are you talking about? Kyle

 

[doug293cz]

Not to contradict, but every once in awhile that airlock will stick in the gasket and blow the lid off a bucket and the gasket out of the lid. It may also lift the lid off a fermentation chamber, all at 62°F.

Which is why the rest of your statement, about using a blowoff tube, is incredibly accurate.

Which is exactly why I said "typically" rather than "always".

Brew on

 

[Lebl468]

I had raisin bits get flicked up into the stem of an airlock and plug it up during a second fermentation on a banana wine. Luckily, I had a garbage bag over the carboy to keep out light, so when it finally pressured the airlock out, it made a "Wacky Waving Arm Inflatable Tube Guy" out of the garbage bag and jettisoned about a gallon of wine all over the bench. A mess indeed.

 

[doug293cz]

I had raisin bits get flicked up into the stem of an airlock and plug it up during a second fermentation on a banana wine. Luckily, I had a garbage bag over the carboy to keep out light, so when it finally pressured the airlock out, it made a "Wacky Waving Arm Inflatable Tube Guy" out of the garbage bag and jettisoned about a gallon of wine all over the bench. A mess indeed.

Rehydrated raisins sound like a great way to plug up an air lock.

Brew on

 

[uncleleon]

Someone post a picture of a fermentation vessel that they have exploded! (Without a propellant)

 

[Gavin C]

Someone post a picture of a fermentation vessel that they have exploded! (Without a propellant)

check this out

https://www.homebrewtalk.com/f14/glass-carboy-explosion-517237/

 

[uncleleon]

Wow! Awesome. er, I mean that sucks for him. I figured pressure would blow the bung out first.

 

[Conan]

A bit of safeguard can be just snipping the 'X' at the bottom opening of your airlocks. That way hop matter and yeast can make it up into the body of the airlock and not plug up the opening and create a miniature Saccromyces-propelled rocket. Kyle

 

[burninator]

I had raisin bits get flicked up into the stem of an airlock and plug it up during a second fermentation on a banana wine. Luckily, I had a garbage bag over the carboy to keep out light, so when it finally pressured the airlock out, it made a "Wacky Waving Arm Inflatable Tube Guy" out of the garbage bag and jettisoned about a gallon of wine all over the bench. A mess indeed.

I know this was probably upsetting for you, but I laughed...a lot...at this visual.

 

[helibrewer]

I heard you can just put on the cap of a bottle on loosely so the co2 can escape and oxygen wont get in. ..... so if its that simple then whats the reason for an airlock? or even those who use condoms?

I attach a blow off tube and leave it through the entire fermentation. It's a nice 1/2" hose that is about 3 feet long so there is very little chance of back-siphoning during the cold crash.

 

[Lebl468]

I know this was probably upsetting for you, but I laughed...a lot...at this visual.

No way! As messy as it was, me and the wife laughed for about 10 minutes before I started cleaning up. It was behind us as we were watching TV, and suddenly we heard a BUMPH!, then what sounded like a 1/20 scale jet engine spooling up to full power, I had no idea what was going on, the my wife exclaimed "S**T!, look at the garbage bag!" Total Waving Tube Guy action.

 

[andy6026]

A bottle cap would fall right through the hole in my fermenter bucket, but a bung and airlock fit just right. And I like to hear it gurgle.

 

[Zepth]

That's twice now you've forgot the most important part of the wacky waving inflatable arm man. The flailing! Wacky waving inflatable arm flailing tube man!

 

[Lebl468]

That's twice now you've forgot the most important part of the wacky waving inflatable arm man. The flailing! Wacky waving inflatable arm flailing tube man!

Do I have to include it, it's already hard enough to say!