Zacher wrote: ↑Mon Oct 02, 2023 6:22 am
So it was better but still only about 40% total conversion. I stirred every 10-15 minutes for 2 hours. Maybe I need a thinner mash?
I checked my notes and here's a recent pretty successful mash for me:
18.5 lb corn meal (from whole kernel feed corn)
10 lb rye malt
5 lb 2 row malt
17 gallons boiling water
I believe that's similar to your recipe. I calculate 2 lb/gal, 1.066 SG @ 100%, 52 lintner
I do my mashes in halves, first half at 12:30 temp was 183F after adding water to corn, next half was at 13:30 temp was 185F after adding more corn and water.
That evening at 18:00 temp was still at 174F
Next morning at 10:30 temp was down to 147F I added malts, down to 142F after mash in.
Next morning after that at 7:30 it was down to 122F so I cooled it to 95F, aerated and pitched yeast. SG was 1.053. I probably stirred a dozen times during the whole process.
I judge that at 80% conversion, best of all it finished dry at 0.998 SG.
So my total gel time was over 18 hours but most of the gelling probably happened while it was over 170F, 6 hours or a little more. My total conversion time was 21 hours. Conversion still only 80% but I was happy with it
You almost certainly don't need to go to this extreme but try holding temps a lot longer than you have.
A sister batch one day behind that one I got 1.056 SG but it finished at 1.012, I ended up with below 6% instead of over 7%. I blame putting the malts in 5F higher producing unfermentables.
Raising your diastatic may help too but the corn has to be well gelled or it's chaff in the wind.
Watch the malt in temp to prevent unfermentables.