Stops around 4.5P

[GlacierBrewing]

Okay, here's one that's stumping me.
I've brewed the same recipe twice now using two versions of the same strain of yeast. It starts around 17P, ferments normally down to about 4.5P then STOPS......(tumbleweed blows across the brewhouse)....The first brew was using our house ale yeast on it's second generation. The second brew was using our house ale yeast, a new pitch, also on it's second generation. I've repitched, roused, transferred and repitched, warmed the tank.....nothing. This yeast has always been a workhorse for me; it's a german ale yeast. The specs from the yeast house show it to be able to hardy and strong. Whadda think?

Prost!
Dave

[kugeman]

Well, that is almost 74% apparent attenuation, which isn't that bad. Are you sure there are still fermentable sugars in the beer? You could pull off 500 ml of beer, add some extra yeast, and throw it on a stirplate if you have access to one. If there's no more fermenation in a day or so, then you have simply used up all of the fermentable sugar.

What is your app. attenuation usually like? What was the mash temperature on this batch of beer? Have you recalibrated your mashtun thermometer recently? (That was the cause of some poor attenuating beers I had a string of in the past. I thought I was mashing at 154F but the thermometer was off and I actually was mashing at 158F. Presto! 68% attenuation!). Have you brewed 17plato beers with this yeast before? What were the results?

The fact that you have had two batches of the same beer, that have been brewed the same way, with fresh pitches of yeast, and you have the exact same problem with both leads me to believe that it's not a yeast problem.

Just some thoughts off the top of my head...

[GlacierBrewing]

Well, that is almost 74% apparent attenuation, which isn't that bad. Are you sure there are still fermentable sugars in the beer? You could pull off 500 ml of beer, add some extra yeast, and throw it on a stirplate if you have access to one. If there's no more fermenation in a day or so, then you have simply used up all of the fermentable sugar.

Ya know Hutch. You're a very smart brewer! 74%. That little nugget popped into my wort-soaked brain about an hour after I posted this thread.

What is your app. attenuation usually like? What was the mash temperature on this batch of beer? Have you recalibrated your mashtun thermometer recently? (That was the cause of some poor attenuating beers

App atten is usually in that ballpark. Mash temp was in the normal range with TWO calibrated thermometers.

I had a string of in the past. I thought I was mashing at 154F but the thermometer was off and I actually was mashing at 158F. Presto! 68% attenuation!). Have you brewed 17plato beers with this yeast before? What were the results?

This is the first 17P beer I've done with this yeast. I don't know why I didn't think of that before the brew!

The fact that you have had two batches of the same beer, that have been brewed the same way, with fresh pitches of yeast, and you have the exact same problem with both leads me to believe that it's not a yeast problem.


No, I agree with you Hutch. I think it's a Brewer-Attention-to-Detail problem. I think I jumped the simple solution for the complex. Kinda a reverse Occam's razor!

Thanks Hutch.

prost!
dave

[Ted Briggs]

If you dont want to change the recipie/proceedure just try some yeast nutriant next time. That will get a little more attenuation.