Keg The Prime vs Keg The Gas - experiment

[Journeyman]

I've noted a strange thing - many people talk about how their best keg beer is at the end of the keg. Since I began kegging I've noted the same - towards the end of a keg the head improves and the flavours smooth out. I've come to a tentative conclusion, that carbonation is only a part of the maturing process - while with bottles we wait weeks before drinking (mostly) with kegs it's "get the bubbles in and get it inya."

Someone here, (Otto or maybe Titan) mentioned it's hard to judge because you can't do a side-by-side comparison so I thought I would give it a go.  

So I am doing 2 kegs the same, one to be primed and the other on serving gas. I have a bottle carb cap so I plan to bottle a beer from the gas keg at 1 week then at 2 weeks, put the primed keg into the fridge and when cold, bottle one from each then 2 weeks later bottle another from each. Then have SWMBO set up a blind test and see what the differences might be. The bottles will be in the fridge so there's no chance of extra ferment happening.

What I THINK might result is, in order of quality, from the least, 1 week gas, 2 week prime/gas, 4 week gas, 4 week prime. 

I've also thought about maybe doing 2 bottles of each step, each time, 1 for the fridge and 12 for the shelf. Just to cover what might happen from carbonation at room temps - would the gas bottles improve given there's no sugar to feed yeast activity?

If any body has suggestions I'd be happy to include them if possible.

The FV's have just gone onto CC. I'll use gelatin finings to clarify them and take care not to add trub to either.

[MitchellScott]

3 hours ago, Journeyman said:

I've noted a strange thing - many people talk about how their best keg beer is at the end of the keg. Since I began kegging I've noted the same - towards the end of a keg the head improves and the flavours smooth out. I've come to a tentative conclusion, that carbonation is only a part of the maturing process - while with bottles we wait weeks before drinking (mostly) with kegs it's "get the bubbles in and get it inya."

Someone here, (Otto or maybe Titan) mentioned it's hard to judge because you can't do a side-by-side comparison so I thought I would give it a go.  

So I am doing 2 kegs the same, one to be primed and the other on serving gas. I have a bottle carb cap so I plan to bottle a beer from the gas keg at 1 week then at 2 weeks, put the primed keg into the fridge and when cold, bottle one from each then 2 weeks later bottle another from each. Then have SWMBO set up a blind test and see what the differences might be. The bottles will be in the fridge so there's no chance of extra ferment happening.

What I THINK might result is, in order of quality, from the least, 1 week gas, 2 week prime/gas, 4 week gas, 4 week prime. 

I've also thought about maybe doing 2 bottles of each step, each time, 1 for the fridge and 12 for the shelf. Just to cover what might happen from carbonation at room temps - would the gas bottles improve given there's no sugar to feed yeast activity?

If any body has suggestions I'd be happy to include them if possible.

The FV's have just gone onto CC. I'll use gelatin finings to clarify them and take care not to add trub to either.

Sounds interesting. I find most of my beers are probably best early as most of my beers are hoppy and that tends to fade as time goes on in the keg. The only thing that improves is clarity. Malty beers though absolutely will improve with age.

One thing to note is the keg that is naturally carbed will have a decent amount of yeast in the bottom after carbonation is complete. This will probably need to be cleared out through the tap before bottle the sample.

Mitch.

[Journeyman]

1 hour ago, MitchellScott said:

Sounds interesting. I find most of my beers are probably best early as most of my beers are hoppy and that tends to fade as time goes on in the keg. The only thing that improves is clarity. Malty beers though absolutely will improve with age.

One thing to note is the keg that is naturally carbed will have a decent amount of yeast in the bottom after carbonation is complete. This will probably need to be cleared out through the tap before bottle the sample.

Mitch.

Yes, I thought of that. I might have to do the noble sacrifice and drink the 1st pint.  

I'm currently looking around to find the right carb levels for a keg - so far seems to be maybe 1/2 the per litre amount for bottles, which at 2 carb drops is (I think) about 8g/L. I figured I'd go to 4g/L.

[MitchellScott]

5 minutes ago, Journeyman said:

Yes, I thought of that. I might have to do the noble sacrifice and drink the 1st pint.  

I'm currently looking around to find the right carb levels for a keg - so far seems to be maybe 1/2 the per litre amount for bottles, which at 2 carb drops is (I think) about 8g/L. I figured I'd go to 4g/L.

https://www.brewersfriend.com/beer-priming-calculator/

[Journeyman]

13 minutes ago, MitchellScott said:

https://www.brewersfriend.com/beer-priming-calculator/

Well that's more than I thought. 2.2 vols = 101 g sugar. I was thinking maybe 80 tops given 8g/L for 19L is 159g. And I was guesstimating the 8g by 2 carb drops @ 3g per 750ml.

Thanks.

[Mark D Pirate]

@MitchellScott

3.68 g / L works very well , ( 70 g of white sugar in corny)  

[Journeyman]

1 minute ago, Mark D Pirate said:

@MitchellScott

3.68 g / L works very well , ( 70 g of white sugar in corny)  

Is that a 2 week carb time to give a good carb level?

[MitchellScott]

Ah shoot, yeah, I forgot about the kegging situation - that calculator is based for bulk priming.

As Mark said, 70 odd grams works pretty well from what I have heard but I have never actually naturally carbed a keg so can't say from experience.

Cheers.

[Journeyman]

I miscalc'ed a bulk prime for my coffee stout and did 170g (from memory) for 20L - don't know why but I had in mind carb drops were 4g each so 10.6 g/L ((8/3)x4)

No bombs but I have to pour VERY carefully or I get a nice glass of stout with a slow Vesuvius out of the bottle.  'No 'glug' sounds while pouring, or else.

Note to self - ALWAYS check your assumptions!

[Pale Man]

What happens when the sugar primed keg is ready to drink? Just add poring CO2? I've never understood this process.

I've got four brand new kegs on the way to start my kegging journey and will want to age a stout or something similar.

[Journeyman]

6 minutes ago, Pale Man said:

What happens when the sugar primed keg is ready to drink? Just add poring CO2? I've never understood this process.

I've got four brand new kegs on the way to start my kegging journey and will want to age a stout or something similar.

Once it is primed at room temp (or ferment temp) you just stick it on the gas at serving pressure. I plan to burp it first as I have no way to test what pressure will build up from the priming. Then let it come down to fridge temp and it should be right to go. I'd guess there is a period where it absorbs CO2 as it cools down - given other comments around the sites about how long to leave a keg after pressure changes I'm thinking next day, 24 hours, should be plenty, given it is already carbed.

[Journeyman]

9 minutes ago, Pale Man said:

I've got four brand new kegs on the way to start my kegging journey and will want to age a stout or something similar

You're gonna need a bigger boa...  I mean, unless you are exceedingly parsimonious in your libation, 4 kegs ain't gonna cut it.  

[Boozadog]

51 minutes ago, Journeyman said:

Well that's more than I thought. 2.2 vols = 101 g sugar. I was thinking maybe 80 tops given 8g/L for 19L is 159g. And I was guesstimating the 8g by 2 carb drops @ 3g per 750ml.

Thanks.

Im thinking that sugar amount actually isn't enough or maybe it's is but time relavent and temp relevant is needed anyhow  

Firstly I do like carbanation in my beer

I primmer a keg of pale ale about 3weeks ago as I didn't have any CO2 anyways as per the a thread I asked others 

( primary/purgless) 

Anyways the advice of others which I respect was about 60g/70g but the priming calc suggests 148g dextrose I wanted like 2.6volumes I wimped out last minute and did 101g as a 50/50 based on both advice and maths i left the keg for 2weeks room temp.

Hooked up to CO2 10/12psi chilling 24hrs 

Poured clear no head little carbanation

Left again 24hrs again on CO2 still similar results.

I spat the dummy turned up the CO2 to 30psi did the hole (rock and roll force carb for2mins)BIG MISTAKE I think

 I purged the keg and put back to serving psi and checked a few hrs later my Clear beer was now cream beer stired up the trub.

Anyways I've let it now sit for about 4 days amazingly have made a beautiful tasting (Mango pale ale )

Still nowhere as clear as the original pour that  I thought was under carbed but my cream beer is now

(ye oldlee Mango pale ale)

My point is my shake mistake aside 200g may have been what I needed  to naturally prime the keg to a good CO2 volume ,I see various recipe's that call for this amount when kegging and I'm Not saying others aren't right and or the calculator online is wrong but in this situation for me that amount of sugar 101g like above id say that carbanation volume was luck to be 1.5vol

Or maybe it's more time and temperature aswell.

[Journeyman]

3 minutes ago, Boozadog said:

did 101g as a 50/50 based on both advice and maths i left the keg for 2weeks room temp

Any idea what the 'room temp' was for that time?

I'm planning on a cupboard with an electric blanket on an STC1000 controller. (like the cheaper Inkbird one but el cheapo from ebay - was a bugger to get working but eventually did a rewire and new probe. Should be good enough to keep it circa 18 - 20° in there.

[Otto Von Blotto]

Personally I don't think the carbonation method has much to do with the beer seemingly being better at the end of a keg, it's more to do with it sitting chilled for a period of time

A better way to test that idea would be to do two identical batches a few weeks apart then try a glass from each keg once the second one is chilled and carbonated, since the first would already have been chilled for the few weeks. 

There may be small inconsistencies between each batch but if you pay close attention to detail, it shouldn't be enough to make any noticeable difference in flavour. 

[Journeyman]

3 minutes ago, Otto Von Blotto said:

A better way to test that idea would be to do two identical batches a few weeks apart then try a glass from each keg once the second one is chilled and carbonated, since the first would already have been chilled for the few weeks. 

Good for the next batch perhaps - one of my XPA's just blew so once I clean that I will have space for 2 kegs in there so 1 will be this test keg and I can do another after that. I have an IPA that can't be far off and I can make a determined effort on the Old English...

[Pale Man]

1 hour ago, Journeyman said:

Once it is primed at room temp (or ferment temp) you just stick it on the gas at serving pressure. I plan to burp it first as I have no way to test what pressure will build up from the priming. Then let it come down to fridge temp and it should be right to go. I'd guess there is a period where it absorbs CO2 as it cools down - given other comments around the sites about how long to leave a keg after pressure changes I'm thinking next day, 24 hours, should be plenty, given it is already carbed.

Sort of making sense.

[Pale Man]

1 hour ago, Journeyman said:

Once it is primed at room temp (or ferment temp) you just stick it on the gas at serving pressure. I plan to burp it first as I have no way to test what pressure will build up from the priming. Then let it come down to fridge temp and it should be right to go. I'd guess there is a period where it absorbs CO2 as it cools down - given other comments around the sites about how long to leave a keg after pressure changes I'm thinking next day, 24 hours, should be plenty, given it is already carbed.

So in layman's terms for me. Your keg is just a big bottle? Prime it, seal it, condition it, then when ready gas for serving?

[Boozadog]

1 hour ago, Journeyman said:

Any idea what the 'room temp' was for that time?

I'm planning on a cupboard with an electric blanket on an STC1000 controller. (like the cheaper Inkbird one but el cheapo from ebay - was a bugger to get working but eventually did a rewire and new probe. Should be good enough to keep it circa 18 - 20° in there.

It was at around 20 maybe down to about 13 overnight on some cold nights was just in my kitchen next to my fv but I have a temp gauge near it I monitor with bottled brews but aim for around 18/21target 

[Journeyman]

14 hours ago, Pale Man said:

So in layman's terms for me. Your keg is just a big bottle? Prime it, seal it, condition it, then when ready gas for serving?

You got it!  

[Journeyman]

14 hours ago, Boozadog said:

It was at around 20 maybe down to about 13 overnight on some cold nights was just in my kitchen next to my fv but I have a temp gauge near it I monitor with bottled brews but aim for around 18/21target 

I'd hazard the temp overnight may be the reason for the lack of carb. The bottles and I presume kegs, seem to lose heat faster than it comes back up - which seems logical - heat radiates, cold doesn't.

So with a few degrees drop, your yeast goes to sleep and it doesn't fire up again until it's almost back to ferment temps. At a guess your brew spent most of the time well below ambient. From what I've read and experienced those first few days in particular it's important the brew doesn't drop below a good ferment temp.

[Pale Man]

5 hours ago, Journeyman said:

You got it!  

I'm reading on another forum you can attach a spunding valve. Apparently gas your conditioning keg to 30 psi and set the spunding valve to 15 psi and it will blow off to that pressure and keep it throughout the conditioning process. Very interesting. Anyone have anymore info on this? Sounds like something I want to do.

[Journeyman]

7 minutes ago, Pale Man said:

Anyone have anymore info on this? Sounds like something I want to do.

Why? That's the question that matters to me. There has to be a good reason for me to add in stuff to successful activity. Corollary of the "if it ain't broke" saying, "if it's working don't mess with it."  

So what would be your expected gain from doing it?

[Pale Man]

3 hours ago, Journeyman said:

Why? That's the question that matters to me. There has to be a good reason for me to add in stuff to successful activity. Corollary of the "if it ain't broke" saying, "if it's working don't mess with it."  

So what would be your expected gain from doing it?

I don't know. I'm just researching for the correct way to do it? I guess you know exactly what pressure is in the keg that way.

What would you do? Prime and fill the keg, seal it and chuck some gas on and leave it. How much pressure would you put on? I'm all ears

[Journeyman]

16 hours ago, Pale Man said:

I don't know. I'm just researching for the correct way to do it? I guess you know exactly what pressure is in the keg that way.

What would you do? Prime and fill the keg, seal it and chuck some gas on and leave it. How much pressure would you put on? I'm all ears

I'll prime and fill then seal it in the cupboard. Not really concerned too much about the pressure inside until the 2 weeks is up. Then stick it in the fridge till cold, burp it and put it on gas at my normal 12 psi. 24 hours later, do the bottles.

I haven't looked much at the 'ferment under pressure' idea, which is where the spunding valve stuff comes from I think. I'm lazy - do the minimum and the more fancy it gets, from what I have seen, the more work and the more chance of things like infection. I could easily be wrong because, as I said, I haven't looked closely, but it seems to me there are a slew of possible things to go wrong being posted about once you move away from the simple ferment -> bottle or ferment -> keg.

I'm not even sure I'll be continuing the partial mash idea except occasionally - depends how well these 'experiment' kegs turn out. Also I have just ordered the 1st LME cans from Coopers so will see what difference they make. If it is as much as the guys on here claim, that might just do me as a standard action.

KISS and have a lazy life is my ideal.  Partial mashes are about as much work as I want to put in and the AG guys seems to have a whole new layer of issues, things to go wrong and time to brew.