Planning on brewing a Berliner Weisse and souring using lactobacillus brevis. I wanted to try kettle souring (well actually "fermentor souring"), tossing a starter of pure lacto into the wort for a few days until appropriate sourness obtained. It sounds like getting a really oxygen deplete environment is best for this part and I contemplated doing this in a CO2 purged corny keg. My question is: should I expect significant CO2 buildup? Will it be enough to simply burp the keg every 12 hrs or so? From my research is sounds like L. Brevis can be heterofermentative and produce both alcohol and CO2, just not sure how much.
Benefits to doing this in the keg would be easy sampling (just put a picnic tap on keg) to hit the sourness just right. I'm not looking to make some co2 bomb in the garage though. Any thoughts?
Also is there any benefit to boiling after the lacto is done to sterilize wort? I don't mind some continued acidification/souring of the wort to go along with the primary sach fermentation. Can't think of any other reason to do this step.