Blending old and young sour beers: carbonation

Hi all,

Just wondering how to blend old and young sour beers. Example:

If I have an "old" sour beer with Brett and Lacto at 1.008 stable for a couple of months.

I have a freshly fermented beer sitting at 1.006 fermented with Sacc.

Now, is there some rules/guidelines/calculations for priming sugar when blending beers like this? I assume the Brett from the old beer would start ferment the leftover sugars in the young beer? I guess the amount of priming sugars depends on the old/young ratio, the FG etc?

Cheers

Short answer is no, there aren't any guidelines when blending beers you don't have a lot of experience with.

If the older beer is stable at 1.008, what would lead you to believe it will further ferment the young beer which is already at 1.006? I'm not saying the brett from the old beer won't drop the young beer any if you blend them, but there's really no way of knowing. When lambic is blended to make geuze, the blender has a pretty good idea (I'd say they know, but even they can make mistakes) what the final gravity of their product will be and know how much young lambic to blend to provide the desired carbonation and flavor. In your case, working with two unique beers you've never brewed before, making an educated guess will be rather difficult.

You know what... I would just blend it on taste (I planned to blend old lambic and fresh APA too...), add regular amount of sugar, wait the usual 2-3 weeks for carb, and then keep it cool. If the brett/lacto are going to eat the residual sugars of the young beer.... well it's not gonna happen quickly, so you have time to monitor the carbonation, and when it's at the right level, you can cold crash it and it will stops any activity.

Or you carb on the low side, and when you feel that the carb is going on the high side, with age, you can cold crash it then.

I would go this way because, as TNG said... you need decades of experiences on similar beers to develop this art of blending.

Thanks guys.

I listened to an interview with Jester King and they said that they blended something like 80% young beer with 20% old beer. I would be nervous in that case without any kind of calculations. But I guess they could have tested this on a couple of bottles first. Experience might be the key here.

But why would the Brett in the old beer not consume the leftover sugars in the young beer? Would the added priming sugar be easier/faster to consume?

Stiltzkin said:

Thanks guys.

I listened to an interview with Jester King and they said that they blended something like 80% young beer with 20% old beer. I would be nervous in that case without any kind of calculations. But I guess they could have tested this on a couple of bottles first. Experience might be the key here.

But why would the Brett in the old beer not consume the leftover sugars in the young beer? Would the added priming sugar be easier/faster to consume?

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Is the 'old' beer brett and lacto only or did you add brett after a sacc fermentation?

Old beer is mixed primary: Sacc, lacto and Brett.
Young beer is only Sacc.

Stiltzkin said:

Old beer is mixed primary: Sacc, lacto and Brett.
Young beer is only Sacc.

Click to expand...

Ok, so again, if the brett in the older beer stopped at 1.008, why do you think it will ferment the younger beer already at 1.006 further?

Brett can work on longer chain sugars that sacc can't. It doesn't know what the SG is and doesn't have a magic number to tell it when to stop. The Brett can almost certainly take the young beer down a few more points.

I doubt it will go any lower than that. Brett really only super attenuates when pedio is involved. Did you use a blend or just a vial each of brett lacto and sacc for the old beer?

Actually it's not only Pedio, a more acidic ph is what makes Brett attenuate in the high ranges. THe reason blending old and young beer in lambic breweries and gueuzeries is because of the turbid mash involved and the very complex wort. The young lambic isn't finished fermenting at all unlike your your sacch blonde at 1.006. You may get bottle fermentation enough to carb but it would probably take months on its own with no priming solution added.

kaips1 said:

Actually it's not only Pedio, a more acidic ph is what makes Brett attenuate in the high ranges. THe reason blending old and young beer in lambic breweries and gueuzeries is because of the turbid mash involved and the very complex wort. The young lambic isn't finished fermenting at all unlike your your sacch blonde at 1.006. You may get bottle fermentation enough to carb but it would probably take months on its own with no priming solution added.

Click to expand...

Fair enough.

BryanThompson: The old beer is fermented with yeast from vials and some bottle dregs.

Just out of curiosity, in what range do you think the SG of young lambic is when they blend it?