Adding Juice to Keg

[troglodytes]

So I'm about to keg a sour that's been sitting about a year now. The beer itself is a bit lacking in complexity and really quite sour (recent pH reading was 3.05pH). I've been thinking of ways to experiment with this one and was about to add 16-24oz of tart cherry concentrate to a keg and rack on top...but I figured I should check in here first.

I'm thinking at keezer temps and no sacch left alive after a year in these harsh conditions the juice shouldn't really ferment much by the time the keg is finished 1 -2 months. Am I correct in my thinking? I just don't want to severely over carb in the keg (I don't have a spunding valve). I understand that I'm not raising abv and am essentially back sweetening, but I'm up for the experiment as the pH is so low, some back sweetening could make for something really pleasant, especially as we get into spring.

Any of my assumptions off base?

 

[sweetcell]

my main concern with your pan is that adding tart cherry juice will not reduce sourness. if you're looking to cut sourness, i would consider going with sweet cherry juice.

you could also try blending in another beer. if you don't have one handy, brew up a very-low IBU wort (could even use extract) and ferment with belle saison/3711 or some other high attenuator.

sacch is dead, but brett is still active in there. at fridge temps you'll get a bit of activity, but probably won't get much over 1 or 2 months. i'd keep an eye on carbonation levels, and if they start getting too high then bleed the keg a bit.

 

[troglodytes]

Perfect. Bleeding off some excess CO2 was my plan in case there was some activity in the keg.

I should note that me wanting to add cherry juice has more to do with wanting to add some complexity then lowering sourness levels. But the addition of sugar will naturally lower the perception of sourness even if it just as tart (I would assume). I personally love it super sour and stoked that my house culture is now at a point where it lowers pH so much. I toyed with the idea of blending with another beer, but I've never fruited anything and thought this might be the best opportunity since this batch cost me close to nothing and its ready to go in the keg.