Using CO2 in bottling from a bucket fermenter

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Paulus

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Hi All,
I've had an idea about using CO2 in bottling from a fermenter to a mixing bucket then to bottles.
I would like a sanity check before investing in equipment so please feel free to say yes or no if it has been done before or just won't make any difference.

I brew from kits, I am still trying to get the fermenting and bottling as good as I can before going BIAB.

My system is a plastic bucket fermenter, from where I siphon the beer to another bucket with a rehydrated DME solution for mixing. I then siphon from the 2nd bucket
to the bottles.

I believe that there is room to improve the process by partially filling the 2nd bucket with CO2 and do the same with the bottles immediately prior to filling.

From what I understand CO2 is heavier than air so the beer in the fermenter bucket won't come into contact with air when the lid is removed. If the 2nd bucket has CO2 in the base then
filling this bucket from the siphon into the bottom of the bucket will just push up the CO2. The same goes for filling the bottles?

Does this sound right? I don't have the capacity to brew at pressure and I only want the beer in bottles not kegs.
 
I think you will find you just a mixture of CO2 and air, the two will combine.
Far better to skip the transfer process altogether and dose each bottle with your priming solution. Bottle directly from your fermenter hopefully using a tap installed near the base. The tap would be high enough to be above the tub. Far gentler on the beer, less process, less room for contamination and oxygen contact.
I have always argued that dosing each bottle with standard white sugar or Demerara sugar is my preferred choice in almost all styles.
 
Some will say you’re overthinking it and it’s not necessary. Oh, they just did. But I like a bit of unnecessary complication 😂. I’ve done something similar but with pressure barrels. The trick is to keep the CO2 in the circuit. Assuming you’re going to the expense of buying a gas regulator and cylinder what I do is….
1. Fill a sanitised barrel with cold tap water, fit the lid then use the CO2 to push the water out thus filling the barrel with CO2.
2. Connect a gas line from the barrel to the bucket lid and a beer line from the bucket tap to the barrel.
3. With the bucket higher than the barrel the beer will flow from the bucket and the CO2 will fill the space left in the bucket.
Are you keeping up?
4. The barrel, when full, can then be pressurised to dispense beer into CO2 flushed bottles using a counter pressure bottle filler.

All, a very costly process with questionable gain.

Hope that helps acheers.
 
Hi All,
I've had an idea about using CO2 in bottling from a fermenter to a mixing bucket then to bottles.
I would like a sanity check before investing in equipment so please feel free to say yes or no if it has been done before or just won't make any difference.

I brew from kits, I am still trying to get the fermenting and bottling as good as I can before going BIAB.

My system is a plastic bucket fermenter, from where I siphon the beer to another bucket with a rehydrated DME solution for mixing. I then siphon from the 2nd bucket
to the bottles.

I believe that there is room to improve the process by partially filling the 2nd bucket with CO2 and do the same with the bottles immediately prior to filling.

From what I understand CO2 is heavier than air so the beer in the fermenter bucket won't come into contact with air when the lid is removed. If the 2nd bucket has CO2 in the base then
filling this bucket from the siphon into the bottom of the bucket will just push up the CO2. The same goes for filling the bottles?

Does this sound right? I don't have the capacity to brew at pressure and I only want the beer in bottles not kegs.

As others have said, not worth it. Whilst decanting into the second FV (or filling bottles) the beer gets slightly aerated but as you are giving the yeast some food they will wake up and use the O2 along with the sugar.

If you were not adding the sugar to carbonate (say if you were going to force carbonate in a cornie) then using some form of CO2 flushing is worth it.
 
Whilst decanting into the second FV (or filling bottles) the beer gets slightly aerated but as you are giving the yeast some food they will wake up and use the O2 along with the sugar.
The yeast will wake up and use up the O2. But it's not an instantaneous process and the oxygen during the time between oxygen uptake and the oxygen being metabolised by the yeast, it can oxidise the beer. Some styles can benefit from this, and it can be detrimental to other styles like heavily hopped ales.

I've also heard that the yeast will metabolise most but not all of the oxygen but TBH the biochemistry of how much and how quickly the yeast metabolises the O2 is beyond me. DocAnna has posted about this before.

In addition to this, there is more oxygen in the headspace at the top of the bottle than dissolved in the beer after transfer. There is a good thread on reducing the headspace to ~5mm (ie filling up almost to the cap) that reduces oxidation of the beer somewhere on the forum. I do this with all my hoppy beers now.
 
Re headspace, if you’re carbonating in the bottle use PET bottles and squeeze them after filling to get the beer up to the bottle rim then screw the cap on. As the beer carbonates you loose the dent and gain a CO2 headspace.
 
Put it down to my OCD. Each to their own, I enjoy devising (to some) pointless and complicated processes/gadgets while others enjoy playing with sparrow’s farts 😂. I’m not saying anything negative about sparrow’s farts ashock1
 
Yeast will not take up any oxygen when bottling, if it did there would be no oxidised beer and breweries wouldn't be going to the expense of purging bottles as they fill them. The only way yeast will take up oxygen in the bottles is by dosing with fresh yeast.
What does happen is yeast produces sulfites (lager yeast produces the most) and this is a flavour-stabilising antioxidant while consuming the priming sugar
 
Yeast will not take up any oxygen when bottling, if it did there would be no oxidised beer and breweries wouldn't be going to the expense of purging bottles as they fill them. The only way yeast will take up oxygen in the bottles is by dosing with fresh yeast.
What does happen is yeast produces sulfites (lager yeast produces the most) and this is a flavour-stabilising antioxidant while consuming the priming sugar

Ooooo now that is interesting. Do you have any articles or links for further reading.
 
Yeast will not take up any oxygen when bottling, if it did there would be no oxidised beer and breweries wouldn't be going to the expense of purging bottles as they fill them. The only way yeast will take up oxygen in the bottles is by dosing with fresh yeast.
What does happen is yeast produces sulfites (lager yeast produces the most) and this is a flavour-stabilising antioxidant while consuming the priming sugar

I was sure it did, I'm sure I remember it from something I read a while ago in the Fix book or the yeast book from the yeast, water, hops, malt series.

I can understand the big breweries being paranoid during packaging when they either pasteurise or centrifuge the beer before packaging to remove the yeast.

I'll read your link and see if I can find my source 🫤.
 
I was sure it did, I'm sure I remember it from something I read a while ago in the Fix book or the yeast book from the yeast, water, hops, malt series.

I can understand the big breweries being paranoid during packaging when they either pasteurise or centrifuge the beer before packaging to remove the yeast.

I'll read your link and see if I can find my source 🫤.

Crikey, your link was a hard read :oops:.

Some interesting stuff there, though, and I liked that one of the referenced articles was written by someone called Saison:D.

What I picked up was :-

Re-innoculating during bottling is the preferred method if you are going to bottle condition. They don't talk about just sticking in more fermentables. Possibly because they just take it as read that it isn't the most effective. Could also be because they are being paid to develop a superior industrial/commercial yeast wink....

It is most effective with yeast starter in a sucrose medium (not dry and not in wort although they acknowledge it
is common to add yeast from the next batch's krausen).

That re-innoculating even without adding more fermentables improves beer stability. Very interesting that.

The bit about using a sucrose based starter makes me think that instead of making a sugar solution and using that to bottle, it would be interesting to prepare the solution in advance and put some yeast in it so that it 'hits the ground running' when you add it to the bottle. Not sure how long 'in advance' would be, day before ? Or how much yeast to add :confused.:

Good article.
 

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