How Much Saved Wort for Natural Keg Carbing?

[zgardener]

I've been kegging for about 5 months now, and I have found that while naturally keg carbing with corn sugar gives a much better mouth feel and creamier head, it leaves a strange off flavor as opposed to force carbonating. I figured before I give up on naturally carbonating kegs all together I'll try adding some saved wort when kegging.

I've done some searching on HBT, but to my surprise I haven't found much about how much saved wort to add for a specific volume of beer. Is there a spreadsheet or formula out there that will take finished volume of beer being kegged, the gravity of unfermented saved wort, and the desired level of carbonation into account so as to suggest the volume of saved wort needs to be added?

 

[nebben]

I don't really know much about this, so first off I apologize for even responding!

But one thing I seem to recall is that a lot (some?) of German breweries use this technique to bottle carb their beers. For whatever that's worth...

 

[motobrewer]

https://www.homebrewtalk.com/f35/kaisers-krausen-article-210796/

http://www.braukaiser.com/wiki/index.php?title=Kraeusening

 

[zgardener]

https://www.homebrewtalk.com/f35/kaisers-krausen-article-210796/

http://www.braukaiser.com/wiki/index.php?title=Kraeusening

Thanks motobrewer, excellent stuff! Exactly what I needed! I'm going to try to find time this Sunday to do my nut brown, we'll see how this goes in a few weeks!
Have you tried either of Kais' discussed methods? Either Speise or Kraeusening? If so, how'd they come out?

 

[motobrewer]

i've never tried to krausen.

 

[Golddiggie]

http://www.braukaiser.com/wiki/index.php?title=Kraeusening

This one made my head hurt trying to wrap it around all the freaking math... Please tell me there's a calculator to help with this (someplace)...

Also, if the fermenting wort isn't at the tolerance level for the yeast in use, can't you just use the yeast that's left in it? I've gotten into the habit (already) of using a secondary fermenting carboy, so I leave a good amount of drek in the primary. Would I want to set some of that aside? The amount stated to reserve of that is more than a bit vague... I mean, how are you supposed to know (when you're doing this for the first time) with a volume of "..until you have enough yeast."... How much is 'enough yeast'?? Are we talking 1oz, 2oz, more, less? At what point (in yeast tolerance vs %ABV of the brew) do we even need to do this part?

While I would like to do whatever possible to make my beers better, this seems like it has far too many variables than I want to deal with (right now). Especially since there's no guarantee that the wort will ferment to a specific FG number. So you really won't know how much to reserve for priming later.

If you follow proper sanitation procedures, do you NEED to boil the reserved wort?

 

[zgardener]

This one made my head hurt trying to wrap it around all the freaking math... Please tell me there's a calculator to help with this (someplace)...

It wouldn't be hard to set up a spread sheet with the formulas on Kai's wiki, I'm waiting on a premium membership for Xmas, so if I get what I ask for, I'll work up an excel file and post it.

If you follow proper sanitation procedures, do you NEED to boil the reserved wort?

As for sanitation... I assume that you wouldn't need to, but you might as well go thru the effort of properly canning the wort as if you would for preserves to ensure that it stays sterile, which, to me, sounds much labor intensive than just boiling for 10 minutes and cooling in the freezer for another 30.

 

[Golddiggie]

I'm also trying to figure out how much actual sugar content is inside the must I have reserved... I have the gravity for it, and such, but just can't remember (or find online, for some reason) how the numbers convert... I know there's a direct relationship between gravity and amount of sugars in solution.

I do like what priming with honey brings to the brew, for flavors and such, so I might just continue using that method. Or go with using some DME (same as what I used in the brew) for priming. Less additional variables to try and factor into the equation.

Part of what makes me not comfortable with the reserved wort method is for at least the first few times, you're probably going to reserve either too much, or not enough... It's easy to get the OG, but the FG doesn't always go to plan.

I'll probably use up the rest of the reserved must in the next starter, or two... Then it really won't be an issue of how much to use of that... I was thinking of using it to back-fill what I lost with hydrometer samples (of the must) but I've just been making sure everything that touches it is sanitized and haven't had any issue (a pretty common practice in mead making I'm finding)... Once you pass the 1/3 break point, you take far less samples anyway.

 

[zgardener]

I usually brew up about 6 gallons, so saving too much or too little isnt really an issue, about 5.5 gallons goes into the fermenter, allowing me to yield a full 5 gallons, and still have .5 left over to save for priming or starters.

I'm sill pretty green with this method, but I'm intrigued, and always looking to try something new and step up my game. My biggest issue is that I wont be able to get the most accurate volume measurements unless I use a bottling bucket and then transfer from there, which means more sanitation, and more chances that an infection can be picked up.

 

[Golddiggie]

I think it's going to take me a while before I try this method... I've not used the 'priming sugar' yet, and probably never will... So far I've used honey (1.25x more than the sugar weight to get the same CO2 volume) with good results. I'm probably going to use the DME method next, to see how that comes out. Basically, I'm going to use every method except for the standard 'priming sugar' to prime with...