low attentuation from pitching yeast slurry?

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laserghost

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wondering if yeast health could be an issue with low attentuation after one week in the fermenter, or am i checking/posting prematurely? last week i brewed edwort's bee cave rye ipa as my first all grain batch using the biab method. recipe's og: 1.064 and i hit 1.067. to this wort i pitched 1.5 cups of yeast slurry from an american brown i bottled the same day. yeast was safale us-05 and that beer sat in the primary for 1 month. it's og was 1.058 and finished at 1.016 – pretty close to the recipe). i racked that to bottling bucket and swirled up the last bit of slurry then poured 1.5 cups into a sanitized measuring cup, covered, and set it aside for pitching.

the brewday went well. i mashed in at 155 and at the end of 90 minutes i was at 150, but the first 30 minutes or so it was 155–154 i stirred every 15–20 minutes and the temps seemed consistent at different spots in the mash. after boiling i chilled to about 69 and pitched the slurry. i frothed the $@*& out of the wort toward the end of the chilling and then halfway between racking to fermenter i pitched the yeast, and shook up the fermenter to aerate more. then racked the remaining wort and shook it up again. finally i put her to rest in the swamp bath where she's sat in 66–67 degree water. visible fermentation occurred within 36 hours, and a nice thick krausen lasted for maybe 3–4 days with lots of bubbling before it started to fall back in.

so i'm now at 7.5 days from pitching the yeast, and about 6.5 days from visible signs of fermentation. the bubbling has slowed significantly but there are still a few bubbles each minute. the surface now is mostly cleared up but there is a thin layer of yeast still on top. the temp has raised up to about 70 in the bath.

this morning i checked the gravity and it was at 1.023 ... recipe's fg is 1.010. i wouldn't be surprised if the gravity came down another point or two, but it seems like 10–13 points is a long way off at this point.

yes, my thermometers and hydrometer are accurate – i've tested them. the hydro sample did not taste sweet. so i'm wondering if i am checking this too early after about a week, or if i should alter this process for next time.

i usually rehydrate/proof dry yeast, but forgot to proof this yeast slurry. i guess i didn't think about proofing it, but considering it was basically dormant yeast, i suppose i should have added some boiled sugar water to wake it back up before pitching.

any other thoughts or comments?
 
Possibly a higher amount of unfermentable sugars? Looks like you went 20 minutes longer than EdWort's mash and started a degree higher.

What did you do (temp and time) for a mash out?

And FWIW, I sometimes have radically different gravity readings from the top than I do I from the bottom of the carboy. I assume that is b/c the yeast are still at work and circulating the wort but who knows, I am no wizard.
 
+1 on looking at the all-grain mash temps first. They can have a much higher affect on the FG than the yeast.
 
Okay thanks. I am still pretty novice, especially with all grain temps. So 155 would yield more unfermentables than 154?
 
Well maybe not that much more unfermentables than usual but I base that on a 60 minute mash. A 90 minute mash might give you slightly more unfermentables as well but that is just speculation.

More than likely it is something with the yeast.
 
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