Long time listener, first time caller, been having a couple of issues with my rye process I was hoping the hive could help to diagnose. In short: the fermentation results in a wild foam over once the yeast kicks off, and the stripping run from that fermentation runs at a snail's pace. I'm not sure if these problems are codependent or independent.
Here's my protocol:
1) 180 gallons water+400 lbs rye flour into cooker
2) Adjust pH to 5.2 with citiric, add 100 ml bioglucanase, heat to 112 F, hold for 30 mins
3) Recheck, adjust pH if needed, add 200 ml Hitempase, heat to 160 F, hold for 60 mins
4) Recheck/adjust, cool to 152 F, add 50 lbs distiller's malt, hold for 45 mins
5) Recheck/adjust, begin cooling, add 100 ml Amylo 300 below 130 F, send to fermenter with 30 gallons more water, target pitch temp is 83 F, chiller panel set to hold at 85.
This results in a volume of about 250 gallons, gravity of about 1070, fermented to dryness over 5 days. I also mash twice per fermenter.
I've pitched both USW-6, BE-134, and have co-pitched the two, the problems arise regardless of yeast used.
Fermcap is also used.
This is when the problems begin. The fermentation foams over the first night. The first time this happened I split the fermentation into two fermenters (250 gallons into a 550 gallon) the second mash day and there was enough foaming for the half-volume fermentation to throw over about 20 gallons of mash. So that's problem number 1, violent foaming at the start of fermentation.
Problem number two arises on the stripping run. The still heats up at a normal pace (fermentation temperature to 170) in the first hour, then between 170 and 180 hits a wall, taking about an additional two hours to reach anything resembling a boil. Once spirit does emerge I would describe the rate of flow as a trickle, and this is with the steam valve fully open (I run a copper steam jacketed batch hybrid, 250 gallons). I don't run into this problem with GNS-based distillations or with bourbon stripping runs for that matter.
Some additional notes: I switched out 100 lbs rye flour with 100 lbs ground read wheat for one half-fermentation, this fermentation did not foam over although I have yet to distill it. I've also worked with coarse ground rye rather than flour following the protocol above and did not have the above issues. The strangest phenomenon through all this occurred after one distillation that I gave up on. After watching the still trickle for a few hours I turned the steam off, went home, came back the next day, fired the still up again with the same mash in the still, and was able to produce spirit at a normal pace (i.e. recovered the expected proof gallonage for the mash volume in about 6 hours).
So: What's happening? What have I done wrong? How can I avoid doing this again? Is the demon rye flour in itself to blame as is my hunch?