Filling presure barrel keg with CO2 prior to racking beer for conditioning to avoid oxidisation

[Bearfoot Brewer]

Hi guys,

I have had trouble with my brews tasting great and crisp and the end of fermentation, then after racking into a pressure barrel (PB) for conditioning, the flavour is lost to a duller, slightly caramel flavour (still very drinkable! but not ideal..). I highly suspect this is due to oxidisation, and one of my brews which I (accidentally!) purged with CO2 after racking into PB did not suffer with this problem. I have also had this problem when bottling.

So, aside from racking carefully and quietly from fermentor to PB, and then purging with a blast of CO2, I was wondering if it was also worth filling the PB with CO2 prior to racking? as people commonly do with corny kegs.

I would sanitise with VWP, rinse thoroughly, then fill the PB with tap water, open the tap, then carefully give blasts of CO2 (from a Soda stream with S30 adaptor) displacing the water and filling the keg with CO2, prime the keg (80g sugar and 0.3g of sodium metabisulphite to further reduce oxidation), then rack carefully, then give a final purge before leaving to condition.

I know this may seem over the top! But I have had such problems with off flavours which at this point I can only seem to attribute to oxidation. There does also tend to be a fair amount of head space in PB's, this would eliminate the oxygen there, as well as the risk of beer mixing with oxygen when siphoning. I could switch to Corny kegs, however this would be a large expense, and I already own two pressure barrels. On top of this I prefer the aesthetic of barrels over corny's and I prefer to brew traditional English styles, which should, in theory, be less prone to oxidation than NEIPA's and the like.

So has anyone tried this before? I couldn't find any info elsewhere.
Do people think this is excessive and that racking carefully + purging with a blast of CO2 after racking would be enough? And a much more economical use of CO2?

I am due to keg my beer (a tribute clone which I can currently hear happily bubbling away!) in about a weeks time.

Thanks in Advance!

 

[Drunkula]

I don't think it's excessive. If it's cost if you could pipe co2 from a ferment into the barrel post sanitise and seal it. I've even considered lowering a candle in on a wire to consume all the oxygen. Not done it but I would.

 

[Bearfoot Brewer]

I don't think it's excessive. If it's cost if you could pipe co2 from a ferment into the barrel post sanitise and seal it. I've even considered lowering a candle in on a wire to consume all the oxygen. Not done it but I would.

Ohh yes nice suggestions, just need to figure an airtight seal to get siphon into the bung on my fermentor and pump the CO2 into the PB, nice..
Haha the candle Idea is genius as well! Would love to know how effective this is. May just do a rest run and see if/ how long it takes for the flame to extinguish due to lack of oxygen

 

[foxy]

It takes a lot of CO 2 to purge a keg/ PB and even then there will be some oxygen still in there, as Drunkula said if you can use the venting CO 2 from the ferment that would be a great help. If you can run a line from the fermenter to the tap of the PB even better. The problem is, are you sure it's oxidation, being as you mention you are getting it in the bottles as well.
Sure you aren't mistaking caramel for a butterscotch flavour?

 

[terrym]

If you are making up kits it might be homebrew 'twang' which I attribute to cheap or old LME.
More on that here, amongst the many threads on this subject (use the forum search engine)
https://www.thehomebrewforum.co.uk/threads/homebrew-twang.68929/

 

[Bearfoot Brewer]

If you are making up kits it might be homebrew 'twang' which I attribute to cheap or old LME.
More on that here, amongst the many threads on this subject (use the forum search engine)
https://www.thehomebrewforum.co.uk/threads/homebrew-twang.68929/

Thanks for the suggestion, and I started with kits and get where you're coming from. but I am doing all grain brewing. I'll do everything I can do to eliminate oxygen in this current brew and report back

 

[Bearfoot Brewer]

It takes a lot of CO 2 to purge a keg/ PB and even then there will be some oxygen still in there, as Drunkula said if you can use the venting CO 2 from the ferment that would be a great help. If you can run a line from the fermenter to the tap of the PB even better. The problem is, are you sure it's oxidation, being as you mention you are getting it in the bottles as well.
Sure you aren't mistaking caramel for a butterscotch flavour?

yes definitely going to look into pumping CO2 from an active ferment into PB through the tap.
The bottled beer was an IPA with a significant amount of dry hopping, and the hop flavour went very flat leaving only really bitterness, along with that sort of caramel flavour.. I was thinking perhaps the bottling wand was a bit vigorous mixing beer with oxygen in the bottle? Or Oxygen may have been introduced when dry hopping?
Yes you may have a point, potentially the sweetness of my last brew was down to diacetyl and sugars present due to stuck fermentation. I failed to aerate the wort properly and pitched the dry yeast straight in, plus temps were a little on the low side (18*C as opposed to 20). FG was 1.017 when I was aiming for around 1.010. I am now giving the fermenter a long vigorous shake then pitching hydrated yeast and fermentation seems much happier in a warmer room.
.
Hopefully now with aerated wort, hydrated yeast, good temperatures, and increased fermentation time to eat up diacetyl, along with oxygen reducing measures, I will defeat the "homebrew twang"! Fingers crossed.. Learning so much as I go!

 

[foxy]

yes definitely going to look into pumping CO2 from an active ferment into PB through the tap.
The bottled beer was an IPA with a significant amount of dry hopping, and the hop flavour went very flat leaving only really bitterness, along with that sort of caramel flavour.. I was thinking perhaps the bottling wand was a bit vigorous mixing beer with oxygen in the bottle? Or Oxygen may have been introduced when dry hopping?
Yes you may have a point, potentially the sweetness of my last brew was down to diacetyl and sugars present due to stuck fermentation. I failed to aerate the wort properly and pitched the dry yeast straight in, plus temps were a little on the low side (18*C as opposed to 20). FG was 1.017 when I was aiming for around 1.010. I am now giving the fermenter a long vigorous shake then pitching hydrated yeast and fermentation seems much happier in a warmer room.
.
Hopefully now with aerated wort, hydrated yeast, good temperatures, and increased fermentation time to eat up diacetyl, along with oxygen reducing measures, I will defeat the "homebrew twang"! Fingers crossed.. Learning so much as I go!

Aerating the wort, isn't necessary with modern dry yeast, they just don't need it, some you have to still hydrate, but not aerate. When bottling with a wand their is air/oxygen in the bottle, contrary to popular belief the oxygen in the head space will not be taken up by the yeast during carbonation, only the DO will be used. For home brewers who carefully store their bottles there should never be a problem with oxidised beer unless you take forever and a day to drink it.
It is difficult to tell what the problem could be without knowing the ins and outs of your process. I have had an astringent IPA from dry hopping, only a mild case but it was there. For me I didn't mind the bitterness, it was the fact that I knew it shouldn't have been there which upset me the most, that and the fact that I had entered it into a comp.

 

[Bearfoot Brewer]

It takes a lot of CO 2 to purge a keg/ PB and even then there will be some oxygen still in there, as Drunkula said if you can use the venting CO 2 from the ferment that would be a great help. If you can run a line from the fermenter to the tap of the PB even better. The problem is, are you sure it's oxidation, being as you mention you are getting it in the bottles as well.
Sure you aren't mistaking caramel for a butterscotch flavour?

Also, If I was to sanitise my PB, then fill with CO2 from the ferment, then seal it, it would be sat there for a few days, hopefully there wouldn't be infection if it was sealed? Gives me the eeby jeebiez leaving it a few days between sanitising and racking though
The alternative would be to get a demi john of elderflower bubbly on the ferment and pump CO2 straight from there into the PB say, the hour immediately prior to racking.. Hmm I like that option.

 

[foxy]

Also, If I was to sanitise my PB, then fill with CO2 from the ferment, then seal it, it would be sat there for a few days, hopefully there wouldn't be infection if it was sealed? Gives me the eeby jeebiez leaving it a few days between sanitising and racking though
The alternative would be to get a demi john of elderflower bubbly on the ferment and pump CO2 straight from there into the PB say, the hour immediately prior to racking.. Hmm I like that option.

It will stay sanitised, the CO2 sees to that.

 

[Bearfoot Brewer]

It will stay sanitised, the CO2 sees to that.

Thanks, I will give this a go. Going to drill a hole in one of my cork bungs big enough to fit my siphon tube into.

 

[Bearfoot Brewer]

I racked a couple of days ago and I used the technique of sterilising Pressure Barrel, then filling with water, then displacing water with CO2 using S30 canister.
I was surprised how well it worked! I have been using that Hamilton Bard 225g canister for a while, and had a 425g Soda stream with adaptor ready for back up.
As it turns out I didn't even finish off the 225g canister and managed to completely fill the keg with CO2.
Racking appeared to go very well from the tap of the fermentor and siphoned quietly into the pressure barrel.
The beer is of course conditioning at the minute but I will post back how it tastes, so far so good.
Next time I may vent the CO2 from ferment into PB however, as I used way less CO2 than I thought, I may consider using this method again.
Cheers

 

[Bearfoot Brewer]

Success! Best beer I have brewed to date. As Foxy suggested I think the off flavour i was detecting in previous brews was more from diacetyl than oxidisation, so the steady ferment temp and longer 14 day ferment definitely seemed to help with that. The measures to reduce oxidation can only have helped though, it all resulted in a clean, crisp flavoursome summer English pale ale - chuffed ☺