Airlock v sealed feementing

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SJAughton

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Hi All

I'm curious, I understand the concept of airlock and science I'm curious of the benefits however against a sealed (alright) bucket.

I'm going to brew a 40ptz batch lager, I'm weighing up a traditional fermenter lid tightly on against a lid with an airlock.

What is the general thoights? Not just lager nut all beers and ciders?

Thanks all
 
that's a good question, which is what I'm trying to understand.

I see others online snapping lid down with no airlock so wondered if I'm missing something.

To me, I thought airlock a good way to let it ferment and the C02 escape.
 
Many members lay the lid on top of the FV but do not snap it shut the CO2 can then push its way out while stopping bugs getting in and on the flip side many members like to see airlock activity especially when new to the hobby so they know the yeast is doing its thing
 
Does the layer of CO2 prevent bugs and infection getting into the brew?
I thought the airlock was a preventative measure. But nice to see the bubbles 'proving' fermentation was happening.
From what i understand yes the C02 is a barrier (please do correct me if wrong), my concern was if too much C02 builds with no outlet would it then pollute the brew?

Being new I'm still learning, only one batch went bad from too much oxygen so wanna avoid that again
 
Hi All

I'm curious, I understand the concept of airlock and science I'm curious of the benefits however against a sealed (alright) bucket.

I'm going to brew a 40ptz batch lager, I'm weighing up a traditional fermenter lid tightly on against a lid with an airlock.

What is the general thoights? Not just lager nut all beers and ciders?

Thanks all
A "bucket" type fermenter will never be 100% air tight (unless fitted with a seal/clamp arrangement) so the lid will act as a form of airlock, venting CO2 when a certain pressure is reached. An airlock will give you a visual indication of fermentation rate..
 
A "bucket" type fermenter will never be 100% air tight (unless fitted with a seal/clamp arrangement) so the lid will act as a form of airlock,
This may be true with some but my Richies FV has a very good seal and i am 100% sure if i snapped the lid down the pressure would blow it off when the fermentation was at its most active.
 
nothing wrong with open top fermenters other than heavy debris getting in. The biggest risk is in the lag phase where the wort could get contaminated or inoculated by wild yeast potentially affecting the flavour of the final beer. The krauzen should protect the beer from lightweight debris and airborne contaminants and CO2 blanket from oxidation. However you do risk flies getting in. I went around a small brewery based on a farm a few years ago and they had open top fermenters and their first job in the morning was to climb up the stepladders and fish out the dead flies off the top of the Krause as the flies would fly over the top of the fermenter, get instantly overwhelmed by the CO2 and drop into the fermenter. He's since got lids on top of the fermenters, but at the time I wasn't too impressed!!

Plastic buckets can be airtight. The ones I have has a rim that you snap down around the circumference. These are both airtight and very strong so I suspect the pressure would build through fermentation and risk bursting the bucket. Just use an airlock or blow off tube. Not as if they're expensive or difficult to implement.
 
Thanks all, what's the thoughts on fermenter like the coopers krousen collar?

That's seems very different to a bucket and the lid apparently allows for C02 to escape.

But its an opaque container does that impact anything?

I've had 1 batch go bad, I think during racking too much Oxygen it's ended up smelling like TCP...

Rookie error trying to kearn to avoid other errors.
 
The ones I have has a rim that you snap down around the circumference.

I have used both types below in the past and found lids with ridges round the outside (picture one) snap shut and are airtight the plain lids (picture two) are much thinner dont snap on and do not make an airtight seal.

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I initially thought a krausen collar fv from coopers was a good idea but one piece extra to clean albeit less to clean on packaging day as you replace the collar once its past most fermentation. I use a Richies FV which has a tight seal and the airlock lets me know fermentation progress without needing to take a reading. Once the diluted starsan in the airlock equilises it's only a few days from being done IME. I now only measure gravity at bottling time. If the beer is a few points higher than expected I just use less priming sugar at bottling time.

This means that apart from cracking the lid open for a dry hop the only exposure to air is at bottling time and that is bottled direct from the FV
 
I'm curious, I understand the concept of airlock and science I'm curious of the benefits however against a sealed (alright) bucket.
What, precisely, do you understand about airlocks and science?
What does "the benefits ... against [something]" mean?
I'm going to brew a 40ptz batch lager, I'm weighing up a traditional fermenter lid tightly on against a lid with an airlock.

What is the general thoights? Not just lager nut all beers and ciders?
Are you thinking of pressure fermenting? Most plastic barrels are not designed for this. Some of the older barrels will allow the lid to blow off under pressure, but many of the "snap on" lids won't blow and the barrel will probably explode. I caught one just in time when the airlock bung-hold had got clogged up with yeast.
You've either got to invest in pressure fermentation equipment, complete with a pressure relief valve or do open fermentation (covering your brew with a clean cloth to stop things falling into it) or use an airlock of some kind. I often just screw up a bit of kitchen roll and stuff it in the air-lock hole or, if you've got a violent initial fermentation, invert a glass over the hole and leave the lid loose.
 
I know I get a little oxidation when racking / bottling and would say if you're tasting TCP, you have a different issue.
In my experience oxidation leads to a quick loss of the nice flavours of a beer. So maybe it tastes good after a couple of weeks but then flavours tail off quickly. If you get it bad, it's a cardboard like flavour I believe, though thankfully not had one that bad yet.

TCP - fermenting at too high temps maybe? Though understand you have to go some to create these flavours.. Or chlorine in your tap water. That's an easy fix as @Davegase says :)

FWIW, a sanitised airlock as a starting point would be a no brainer for me athumb..
 
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