Author Topic: Not able to raise alcohol level  (Read 261 times)

Offline Gezz

  • 1st Kit
  • *
  • Posts: 3
Not able to raise alcohol level
« on: July 13, 2019, 10:48:19 PM »
Hi all this is my first post! Im relatively new to brewing and have a problem getting my levels do wn to 1.008 as stated in Beer Smith. Its a pilsner and started at 1.055 and has well and truley stopped at 1.030, any suggestions on how fo lower it any further?

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 3679
Re: Not able to raise alcohol level
« Reply #1 on: July 13, 2019, 10:53:28 PM »
First question, how are you measuring gravity?
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline Gezz

  • 1st Kit
  • *
  • Posts: 3
Re: Not able to raise alcohol level
« Reply #2 on: July 13, 2019, 11:56:07 PM »
With a refratometer

Online spurviance

  • Cellarman
  • **
  • Posts: 50
Re: Not able to raise alcohol level
« Reply #3 on: July 14, 2019, 12:02:00 AM »
Refractometers read artificially high when alcohol is present.  There are correction calculators online.
On tap,  Vienna Lager, Doppelbock, Dortmunder Export, Pale Ale, Porter, Saison

Fermenting, Saison

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 3679
Re: Not able to raise alcohol level
« Reply #4 on: July 14, 2019, 12:13:52 AM »
Okay, if that's an uncorrected reading, that could be the problem. 

Refractometers are calibrated to measure the density of a sugar solution -- like wort.  Once fermentation starts and alcohol is in the mix, the readings are  seriously skewed.  But you can still use a refractometer (I do,)  you just have to apply a correction formula for fermenting or fermented beer.  There are calculators available online, Brewer's Friend has one for example.  Maybe someone can recommend another. (I've incorporated the correction into my own spreadsheet, so I'm not too familiar with what's out there.)

I'd guess that you've reached a perfectly reasonable final gravity already.  Maybe not exactly 1.008, but that's just Beersmith's prediction anyway, your actual result will vary because of many factors.

If you already corrected the reading, ignore all that... and try raising the temperature to room temperature to reinvigorate the yeast (assuming this was a cold lager fermentation.)

Good luck, and welcome to the hobby and the forum!
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline Gezz

  • 1st Kit
  • *
  • Posts: 3
Re: Not able to raise alcohol level
« Reply #5 on: July 14, 2019, 12:23:51 AM »
Thanks a  lot you guys I'll look into a correction formular, cheers mate!

Offline mainebrewer

  • Brewer
  • ****
  • Posts: 490
  • Palermo, Maine
Re: Not able to raise alcohol level
« Reply #6 on: July 14, 2019, 10:00:49 AM »
Plugging your numbers into one of the correction tables, your current final gravity is around 1.014. Still high for a pilsner. As Robert suggested, try raising the temp and rouse the yeast.
BJCP Certified

Offline denny

  • Administrator
  • Retired with too much time on my hands
  • *****
  • Posts: 20754
  • Noti OR [1991.4, 287.6deg] AR
    • Dennybrew
Re: Not able to raise alcohol level
« Reply #7 on: July 14, 2019, 02:25:43 PM »
Plugging your numbers into one of the correction tables, your current final gravity is around 1.014. Still high for a pilsner. As Robert suggested, try raising the temp and rouse the yeast.

Not necessarily high if it's an extract pils.  But we have no idea of the recipe, the yeast used, or the procedures.
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts." - Bertrand Russell

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 3679
Re: Not able to raise alcohol level
« Reply #8 on: July 14, 2019, 02:40:53 PM »


Plugging your numbers into one of the correction tables, your current final gravity is around 1.014. Still high for a pilsner. As Robert suggested, try raising the temp and rouse the yeast.

Not necessarily high if it's an extract pils.  But we have no idea of the recipe, the yeast used, or the procedures.

 Not necessarily high either for an all grain depending on the grain bill, mash, etc, and yeast, as Denny says... perfectly normal for many Pilsners with that OG.  75% AA.   Not to worry.
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline Richard

  • Brewer
  • ****
  • Posts: 268
Re: Not able to raise alcohol level
« Reply #9 on: July 14, 2019, 04:02:46 PM »
If you have BeerSmith there is a built-in refractometer correction tool (at least there is in version 3, I'm not sure about earlier versions). It is under Tools->Refractometer. Also, any place you enter a gravity reading on the session tab or after clicking "Add Reading" there is a small button with a picture of a refractometer next to the entry box that will pop up the tool.
Original Gravity - that would be Newton's

Offline mainebrewer

  • Brewer
  • ****
  • Posts: 490
  • Palermo, Maine
Re: Not able to raise alcohol level
« Reply #10 on: July 14, 2019, 05:09:41 PM »


Plugging your numbers into one of the correction tables, your current final gravity is around 1.014. Still high for a pilsner. As Robert suggested, try raising the temp and rouse the yeast.

Not necessarily high if it's an extract pils.  But we have no idea of the recipe, the yeast used, or the procedures.

 Not necessarily high either for an all grain depending on the grain bill, mash, etc, and yeast, as Denny says... perfectly normal for many Pilsners with that OG.  75% AA.   Not to worry.
I stand corrected, I should have qualified my original response.
1.014 is higher than I would want either my German Pils or Czech Pils to finish.
BJCP Certified

Offline Kevin

  • Assistant Brewer
  • ***
  • Posts: 159
  • Free from the Style Police!
Re: Not able to raise alcohol level
« Reply #11 on: July 14, 2019, 05:51:08 PM »
One more caveat when using Beersmith... if you don't customize your equipment profile (and even you mash profile) you are playing a guessing game every time you brew. You can't just click on one of the profiles that comes with the software... those are just starting points for you to build your own. Once you get all the weights and measures dialed in those estimates will be much closer to actual.
“He was a wise man who invented beer.”
- Plato

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 3679
Re: Not able to raise alcohol level
« Reply #12 on: July 14, 2019, 05:52:13 PM »

I stand corrected, I should have qualified my original response.
1.014 is higher than I would want either my German Pils or Czech Pils to finish.
Though just for perspective, Pilsner Urquell finishes at 3.8°P (1.015) from a start of only 12.0°P (1.048,) only 68% AA.  I too aim for a much higher degree of attenuation,  but there's room for variation.
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Online a10t2

  • Official Poobah of No Life.
  • *
  • Posts: 4595
  • Ask me why I don't like Chico!
    • SeanTerrill.com
Re: Not able to raise alcohol level
« Reply #13 on: July 14, 2019, 06:57:07 PM »
Though just for perspective, Pilsner Urquell finishes at 3.8°P (1.015) from a start of only 12.0°P (1.048,) only 68% AA.  I too aim for a much higher degree of attenuation,  but there's room for variation.

Dang, I hadn't realized PU was quite that low-ABV. Although to be 4.4% it would have to finish at 3.6°P (theoretically), but that's getting subtle.

Gezz, another subtlety of using a refractometer is that the actual gravity is generally lower than the refractometer reading, generally by 2-5%. You can determine this wort correction factor experimentally, just by dividing a refractometer reading by the hydrometer reading. The calculator in my signature can apply both corrections once you've determined WCF for your worts.
Sent from my Microsoft Bob

Beer is like porn. You can buy it, but it's more fun to make your own.
Refractometer Calculator | Batch Sparging Calculator | Two Mile Brewing Co.

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 3679
Re: Not able to raise alcohol level
« Reply #14 on: July 14, 2019, 08:20:42 PM »


Gezz, another subtlety of using a refractometer is that the actual gravity is generally lower than the refractometer reading, generally by 2-5%. You can determine this wort correction factor experimentally, just by dividing a refractometer reading by the hydrometer reading. The calculator in my signature can apply both corrections once you've determined WCF for your worts.

Sean, I'm still not convinced this is a thing.  I have two digital refractometers, and both read identically, and dead on correct, as confirmed by comparison with N.I.S.T.-certified brewery Plato saccharometers.  I'm inclined to think that the supposed "wort correction factor" that's become homebrew orthodoxy for the hand-held, optical units is just an artifact of the eyeball-brain complex trying to decide just where that fuzzy blue zone actually cuts off on the tiny little scale, while the digital refractometer knows exactly how to read itself.  When I had a hand-held unit, I could never determine a consistent correction; it depended on what I thought I saw any given day, which a lot of times was right with no correction at all.   We can seem to generate one, but that may just be an artifact of trying to rationalize the artifact of eye-brain fuzziness.  IOW the "correction" is not instrument-specific as claimed, which would throw into question the very notion of precision optical instruments and the science of refractometry, but rather user-specific.  Perhaps beyond this topic, but worth considering.
« Last Edit: July 14, 2019, 08:27:58 PM by Robert »
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.