Membership questions? Log in issues? Email info@brewersassociation.org

Author Topic: Help with English yeasts not fully attenuating  (Read 5553 times)

Offline Wort-H.O.G.

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 4439
  • Play Nice
    • Harvey's Brewhaus
Re: Help with English yeasts not fully attenuating
« Reply #15 on: December 05, 2014, 01:14:40 pm »
ha! i can almost hear the english accent of the yeast whisperer  ;D
Ken- Chagrin Falls, OH
CPT, U.S.Army
https://www.facebook.com/pages/Harveys-Brewhaus/405092862905115

http://braukaiser.com/wiki/index.php?title=The_Science_of_Mashing

Serving:        In Process:
Vienna IPA          O'Fest
Dort
Mead                 
Cider                         
Ger'merican Blonde
Amber Ale
Next:
Ger Pils
O'Fest

Offline Joe T

  • Assistant Brewer
  • ***
  • Posts: 172
Re: Help with English yeasts not fully attenuating
« Reply #16 on: December 07, 2014, 07:03:01 am »
Well I brewed my oatmeal stout and used almost everyone's advice in my quest for better attenuation. I know, I should change one part of my process each time I brew so I will know what works. But I would rather not drink another underattenuated beer. Here's where I made adjustments:
Grist: I actually used more crystal malt, from 3% up to 5%. I decided to try Golden naked oats for the first time and subbed it for crystal 80. The raw grain had such a nice sweet oat flavor I couldn't help myself. I also subbed in 5% cane sugar.
Mash: lowered temperature to 150 and mashed a full 90 minutes. Lowered pH to 5.25.
Yeast: WLP002. Used 7 ounces of thick slurry from a mild brewed 10 days ago. The slurry and a quart of wort went into a carboy for 90 minutes, swirling periodically until it began to foam. The rest of the 64 degree wort was racked on top.
Oxygenation: 90 seconds pure O2 while rocking carboy.
Fermentation: temperature allowed to rise to 68f and sporting a good krausen at 12 hours.

I fully expect better attenuation on this one. If it ends up too dry I'll make adjustments one thing at a time on successive batches, but at least I won't have to drink another under attenuated beer!

Offline jeffy

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 4222
  • Tampa, Fl
Re: Help with English yeasts not fully attenuating
« Reply #17 on: December 07, 2014, 07:14:14 am »
The only thing that sticks out is that you used yeast from a previous batch which may have been under attenuated.  Wouldn't that yeast have been already bred to drop out?
Jeff Gladish, Tampa (989.3, 175.1 Apparent Rennarian)
Homebrewing since 1990
AHA member since 1991, now a lifetime member
BJCP judge since 1995

Offline Joe T

  • Assistant Brewer
  • ***
  • Posts: 172
Re: Help with English yeasts not fully attenuating
« Reply #18 on: December 07, 2014, 08:03:32 am »
The only thing that sticks out is that you used yeast from a previous batch which may have been under attenuated.  Wouldn't that yeast have been already bred to drop out?
I did consider this.
The yeast in question was a vial of wlp002, bought from my lhbs fresh off the UPS truck in winter shipping conditions, and pitched into 5.25 gallons of 1.038 wort @ 2 weeks past the yeast's production date. This should pretty much eliminate the yeast as a variable, for this batch. Attenuation aside, I couldn't imagine a better pitch for my stout. So what are the odds that the variable(s) that caused the under attenuation caused a full genetic adaptation to those conditions in just one generation? I'll take my chances but I won't rule it out in the event of a failure.

Offline hopfenundmalz

  • Global Moderator
  • I must live here
  • *****
  • Posts: 10680
  • Milford, MI
Re: Help with English yeasts not fully attenuating
« Reply #19 on: December 07, 2014, 08:03:56 am »
On calibrating my thermometer, it's been calibrated in an ice water bath at 32.0f. But it reads 208.6 in boiling water at 2000'. Boiling water should be 210f at my altitude, right? This is the thermometer I use: http://www.thermoworks.com/products/low_cost/rt616.html. I'm not sure 1.4 degrees would make that much difference in fermentability. I'll try a longer mash time if it can improve fermentability but according to Braukaiser's chart, I am achieving damn near 100% conversion efficiency.

On limiting crystal malts, I've had the same results with a SMASH beer.

As far as using simple sugar, it's not off the table but but I would prefer to earn my English ale merit badge without it. If others can achieve satisfactory results without it, I should be able to as well.

Thanks again.
208.1F at 2000 Ft.
Jeff Rankert
AHA Lifetime Member
BJCP National
Ann Arbor Brewers Guild
Home-brewing, not just a hobby, it is a lifestyle!

Offline Joe T

  • Assistant Brewer
  • ***
  • Posts: 172
Re: Help with English yeasts not fully attenuating
« Reply #20 on: December 07, 2014, 08:44:48 am »
On calibrating my thermometer, it's been calibrated in an ice water bath at 32.0f. But it reads 208.6 in boiling water at 2000'. Boiling water should be 210f at my altitude, right? This is the thermometer I use: http://www.thermoworks.com/products/low_cost/rt616.html. I'm not sure 1.4 degrees would make that much difference in fermentability. I'll try a longer mash time if it can improve fermentability but according to Braukaiser's chart, I am achieving damn near 100% conversion efficiency.

On limiting crystal malts, I've had the same results with a SMASH beer.

As far as using simple sugar, it's not off the table but but I would prefer to earn my English ale merit badge without it. If others can achieve satisfactory results without it, I should be able to as well.

Thanks again.
208.1F at 2000 Ft.

Really? I always thought the formula was 212@ sea level, minus one degree for every 1000'.

Offline hopfenundmalz

  • Global Moderator
  • I must live here
  • *****
  • Posts: 10680
  • Milford, MI
Re: Help with English yeasts not fully attenuating
« Reply #21 on: December 07, 2014, 09:13:28 am »
On calibrating my thermometer, it's been calibrated in an ice water bath at 32.0f. But it reads 208.6 in boiling water at 2000'. Boiling water should be 210f at my altitude, right? This is the thermometer I use: http://www.thermoworks.com/products/low_cost/rt616.html. I'm not sure 1.4 degrees would make that much difference in fermentability. I'll try a longer mash time if it can improve fermentability but according to Braukaiser's chart, I am achieving damn near 100% conversion efficiency.

On limiting crystal malts, I've had the same results with a SMASH beer.

As far as using simple sugar, it's not off the table but but I would prefer to earn my English ale merit badge without it. If others can achieve satisfactory results without it, I should be able to as well.

Thanks again.
208.1F at 2000 Ft.

Really? I always thought the formula was 212@ sea level, minus one degree for every 1000'.

212 at Sea Level and standard pressure. Atm pressure will have be a smaller adjustment than altitude.
Pressure vs altitude.
http://www.engineeringtoolbox.com/boiling-points-water-altitude-d_1344.html

Presure and altitude can be input on this calculator.
http://www.csgnetwork.com/h2oboilcalc.html



Jeff Rankert
AHA Lifetime Member
BJCP National
Ann Arbor Brewers Guild
Home-brewing, not just a hobby, it is a lifestyle!

Offline Joe T

  • Assistant Brewer
  • ***
  • Posts: 172
Re: Help with English yeasts not fully attenuating
« Reply #22 on: December 07, 2014, 09:18:46 am »
Yup, 1 degree/500'. Funny to have "known" something for so long and and be so wrong all along. That explains a whole lot. Like always coming in low on infusions and decoctions. (Slaps forehead)

Offline hollnagel

  • 1st Kit
  • *
  • Posts: 8
Re: Help with English yeasts not fully attenuating
« Reply #23 on: December 09, 2014, 05:47:26 pm »
I have had very similar experiences with Wyeast 1968 (like WLP002 - very hi floc, very low attenuation). I have brewed my ESB recipe many times with it, attempting several tweaks to dry it out, get a lower FG.  But there seems to be only so much I can do with it.  However, similar to your experience, I have a very easy time getting where I want with American strains like 1056.  I have a theory, would like to pose to others reading: perhaps these hi-floc strains are best suited for different fermenting geometries and conditions (for example, not a tall slender 6-gal carboy)?  One thing I may try next time with my ESB is to pitch two different strains of yeast into the same 5-gal batch, such as 1968 & 1056.  Maybe someone has some thoughts on that as well.

Offline Joe T

  • Assistant Brewer
  • ***
  • Posts: 172
Re: Help with English yeasts not fully attenuating
« Reply #24 on: December 09, 2014, 06:44:22 pm »
Well I brewed my oatmeal stout and used almost everyone's advice in my quest for better attenuation. I know, I should change one part of my process each time I brew so I will know what works. But I would rather not drink another underattenuated beer. Here's where I made adjustments:
Grist: I actually used more crystal malt, from 3% up to 5%. I decided to try Golden naked oats for the first time and subbed it for crystal 80. The raw grain had such a nice sweet oat flavor I couldn't help myself. I also subbed in 5% cane sugar.
Mash: lowered temperature to 150 and mashed a full 90 minutes. Lowered pH to 5.25.
Yeast: WLP002. Used 7 ounces of thick slurry from a mild brewed 10 days ago. The slurry and a quart of wort went into a carboy for 90 minutes, swirling periodically until it began to foam. The rest of the 64 degree wort was racked on top.
Oxygenation: 90 seconds pure O2 while rocking carboy.
Fermentation: temperature allowed to rise to 68f and sporting a good krausen at 12 hours.

I fully expect better attenuation on this one. If it ends up too dry I'll make adjustments one thing at a time on successive batches, but at least I won't have to drink another under attenuated beer!

Sorry to quote myself but I wanted to follow up. Final gravity after 2 days is 1.012. That's around 75% attenuation. After 3 days is 1.012. It has dropped clear and I don't expect it to go lower. My gut tells me the pitching rate was the main factor in the higher attenuation. But there's no way yet. Time will tell if the beer has been improved or not but at least I have achieved my short term goal and I can build from here.

Offline brewday

  • Brewer
  • ****
  • Posts: 453
Re: Help with English yeasts not fully attenuating
« Reply #25 on: December 09, 2014, 06:56:30 pm »
I use 1968 a lot.  Conical or carboy, I consistently get 75%+ AA with it.  I always mash low (mid to upper 140s) and pitch a good starter with plenty of O2.  Ferment @66 for three days then take it to 70 to finish.