Conversion problems with a tried and true

[jon1163]

Mornin...

I started stilling about eight years ago and have had great success with the tried and true recipes here as well as a few modifications of my own. I still all grains and neutrals in a three inch pot and thumper as well as a four inch flute (15.5 gal and 26 gal boilers on hand). In addition to my normal stilling for drinking stock I've been trying to put away a three or five gallon barrel of all grain each year. The intent being to break a new barrel open each year at the five year mark. My last three gallon barrel was HBB aged three years and I'm trying to duplicate it. The problem I'm trying to wrap my head around is that I'm new to large batch mashing and am wondering if I might need to deviate from the HBB tried and true temperatures for mashing or if something else I'm doing might be the issue.

I haven't had problems mashing in ten gallon batches in the past but now I have am mashing in thirty gallon barrels:

My well water is 8ph - pitching Red Star bread yeast at 95F

1. boil water in my 26 gallon boiler
2. dump water into the 30 gallon barrel and add corn, honey malt, oats...wrapping it and stirring every thirty minutes for about three hours. At this point it drops to about 175F - 6.4ph
3. Taste - tastes starchy
*****4. cool with my coil to 155 and add malt and oyster shells. This is where I think something is going awry. The last batch I ran this way I pitched a bit low, 147/150F and wrapped and mashed all night - read 1.05 SG. It wasn't as sweet tasting as normal. When I stilled the 25 gallons I had a horrible yeild, about four pints before cuts. I ran a batch before this one and added grains at 160F and had a much better yield from the 25 gallons, 10 pints before cuts. (1.05 SG). But it seems I should be pulling a bit more volume than 10 pints?

Today and too soon to tell:
I mashed last night and just pitched yeast...same procedure as before except that I added malt at 155/160F and also added Liquid exo-alpha amy, liquic endo alpha amh, and liquid glucosamylase. ph 6.1 after mashing 1.05 SG. Woke up this morning and it tastes sweet as can be but I don't want to have to add, procure, or keep on hand liquid enzymes if I don't have to.

- My theory is that on that bad batch I added malt at too low a temp and didn't convert well. Why though would I have a SG of 1.05 if I didn't convert? Maybe I misread the temp and denatured my enzymes but I don't think this is the case.
- For the next batch I don't know if the 10 pints is a quality yield
- Any other advice regarding anything else you can think of?

Thanks

[Durhommer]

Sounds like you have a solid procedure for what you are doing maybe just a hiccup with the temps. The last batch I made (wheat barley malt rye malt) I did in 10 pound batches and after all done got in the 1060s just keep a close watch on your temps although some will say ph is key too

[Deplorable]

High pH of starting water could be part of yoru problem. Lower your water to 7 to begin with, and you're likely to see better conversion from your malts. Not sure why you added oyster shell to the mash with your malted grains. That shouldnt go in until you pitch yeast if you add them at all. I dont find them to be needed in an AG ferment, and it would seem counter productive to put them in with the malts when they need the acidic enviroment to work.
Using corn meal, malted wheat and rye, and SebStar A&B enzymes my first AG Bourbon Mash using SCDs Easy Large Batch Mashing process and and CROW bourbon recipe, I got 1.074 OG.

[jon1163]

Thanks for the advice. I woke up this morning and found it in three days my mouth dropped to .997 so it appears that I did some thing correct in this last batch. I also have a little space heater in the laundry room turned distillery that I kept around 83° forThe duration of the fermentation.

Thanks for the advice and I’ll read up on adjusting pH prior to mashing. I’m a newcomer to worrying about ph

[Bee]

I agree your pH is too high. Should be 5.2-5.5 when you add your malt. Forget the shells too. Not needed for AG.

ETA: With high pH like that, you'll end up with blue, copper-tainted distillate.

[shadylane]

+1 on the above