Beer_Tigger said:
Maine Homebrewer said:
What was your mashing scheme? Did you do an iodine test?
A high mash temp combined with an incomplete conversion could explain your problem.
Or not if you did everything right. Just a thought.
Ding ding ding!
Sounds to me more like a mashing issue. Did you get all the temperatures accurate? Did you remember to check the "Adjust for equipment temperature" for the mash profile?
I'd concentrate on that next time to make SURE you've converted as per your profile.
You did read the part where he said he mashed at 150F for 60 minutes, right?
I just finished a Scottish 80/- that I doughed-in at 160F, measured with a well calibrated thermometer. It finished at 1.014 from 1.051 using CalAle. I repitched from slurry grown in a 1.034 Scottish 60/-, at 68F. 72% apparent attenuation in 4 days.
This beer is only 50% attenuated. A 60 minute single infusion mash at ANY temperature between 140 and 165 will attenuate more than 50% with ANY yeast. So, unless his thermometer is reading more than a full 10 degrees high...the wort will be more than 50% fermentable.
He also fermented using CalAle at 65F, direct from a smackpack. Many people, myself included (and The Pope himself), have trouble getting CalAle to work at 65. I can get second and third re-pitches to do it (but, its still super slow). I've never gotten a first pitch to work at 65F (yes, I've tried several times), and DEFINITELY not when direct pitching from a smack pack. He kept the smack pack on the counter at room temp and pitched into 65F wort, that's probably a 10F temp-shock.
Even at 1.041 OG, a single smack pack is still underpitching by about 60%, assuming a BRAND NEW, 97% viable pack. If its a month old, or less than perfectly handled then its underpitched by a factor of 2 or more. So, underpitched, with no starter, and pitched into cold wort (from room temp), and kept at a suboptimal temperature for the strain in question. That is a textbook recipe for a stuck ferment.
The only other things he could have done to make it more likely would be to let the temp fluctuate by several degrees, and NOT aerate the wort very well.
Of course, A forced ferment would answer that question for certain...but, that's where my money is.