Ive got a hibiscus gose recipe Im wanting to try since I have plenty of hibiscus blossoms in my back yard. The owner of one of the local breweries suggested kettle souring so I figured Id read on further here. As I read more, it seems my electric RIMS system might be better suited for sour mashing than I thought.
My mash tun is a 70 qt Igloo with a suction manifold and I have a return head for mashing as well as a sparge head. The difference is the mashing head directs wort upward in a gentle stream in the grain bed vs. the typical shower from a sparge. I can adjust the copper tube of the return line to keep it right on top of the grain bed or even below the surface, if I wanted.
Heres what Im thinking:
Do a normal mash routine with protein rest for 20-30 min then infusion at 148 for one hour. Rack off the wort to the boil kettle, boil 10-15 min, rack through my chiller into a purged corny which will come out at +/- 80F in the summer here. I can pitch the additional grain, sparge head is brought into contact with top of grain bed, cover the grain bed with plastic wrap, purge with a CO2 line, then push the wort from the keg back to the grain bed with CO2.
It seems like this would void as much O2 as possible.
I can set my PID to maintain 115 or so and leave the circ. pump on. It should maintain +/- 1F, so I can draw a sample every 12 hours until its reached the sourness I desire. I even thought about just running the circ. pump every 6-8 hours with my RIMS tube powered up as my garage ambient temp is about 90F right now in the summer heat. Biggest temp drop would be in the RIMS tube or plumbing, but that would be an anaerobic environment anyhow.
The brewer I talked to suggested pH 3 to 3.5 would be good for a sour.
Thoughts or suggestions? Im in the same boat as the OP- the $14 cost for bacteria is off-putting to me and I like the idea of experimentation- that is so long as I know no one will get sick
