Over attenuation

[LopeJuice]

Been brewing a lot of hoppy beers lately, almost all using 1056, and they've been finishing much lower than anticipated. Pale ales finishing around 1.04-08

I tried using gypsum but it doesn't seem to have made much of a difference, IPA just finished at 1.07 today and the target was 1.14

Any advice would be greatly appreciated.

 

[BBL_Brewer]

Could you give us a little more info on your brewing process? All grain or extract, what were your OG's, if all grain what are your mash temps that kind of stuff.

 

[sptaylor70]

What was your OG? What was your fermentation temperature? What was your pitching rate? If your OG is low, or your fermentation temperature is high, or if you overpitch the yeast by enough, your yeast can, in some cases, overshoot the mark.

What was your mash temperature? How much Crystal malt did you use (as a percentage of your grain)? Did you use sugar in your wort? Fewer dextrins, from mashing low, or using none-to-not-much Crystal, or using excessive amounts of sugar, can result in a lower-than-expected FG.

My LHBS proprietor has become pretty disenchanted with 1056 due to perceived batch-to-batch variability. You could try US-05, which is the same yeast. Or try Wyeast 1278 Anchor Liberty or Wyeast 1332 Northwest.

 

[MrHadack]

I think we'll need some additional details. Can you add anything along the lines of fermentation temperature, length of fermentation, and starting gravity of the batches?

I'm not sure gypsum would affect the attenuation at all. At least, I haven't seen anything anywhere to suggest that.

 

[Yooper]

I wouldn't necessarily say an IPA finishing at 1.007 is overattenuated- most of mine are in the 1.008-1.010 range which is ideal for an IPA.

Mash temperature and ingredients play the largest role in attenuation, so if you're mashing lower than 151ish, simply try mashing a few degrees higher. Of course an accurate thermometer is a must!

 

[Setesh]

It is possible that your thermometer is inaccurate and you are mashing much cooler than you think you are. Try mashing warmer next time and see if that helps. As Yooper says, an accurate thermometer is a must have. You can even use one of the super fragile lab grade ones since you only need it to calibrate your normal thermometer. As long as you know how far it is off then you can compensate for it in the future.

Also check your hydrometer. I have had them off by as much as 8 points before. It may tell you that your OG is 1.060 and your FG is 1.005 when it was actually 1.065 OG and 1.010 FG.

 

[LopeJuice]

All grain, single infusion, no mash out. Mashing between 150-154 on the last few batches. Recipes have been very simple grain bills, mostly pale malt. Last one had about 3% crystal. OG are around 1.055-65 depending on the style, all have been pale ales or IPAs. Fermenting in a temp controlled fridge at 63f. hope that helps paint a better picture!

was told by my lhbs that gypsum would increase flocculation. so far that hasn't been true, i've been using about a teaspoon in the last couple batches and haven't noticed a difference.

 

[LopeJuice]

It is possible that your thermometer is inaccurate and you are mashing much cooler than you think you are. Try mashing warmer next time and see if that helps. As Yooper says, an accurate thermometer is a must have. You can even use one of the super fragile lab grade ones since you only need it to calibrate your normal thermometer. As long as you know how far it is off then you can compensate for it in the future.

Also check your hydrometer. I have had them off by as much as 8 points before.

thanks for the tips! recently bought a new digital thermometer that I was hoping would be more accurate, haven't checked it against anything else yet though. There is a few points difference between my refractometer and hyrdrometer, wasn't sure which to trust so I've mostly been using the hydrometer but that's a great point! I will look into it, thanks.

 

[Setesh]

thanks for the tips! recently bought a new digital thermometer that I was hoping would be more accurate, haven't checked it against anything else yet though. There is a few points difference between my refractometer and hyrdrometer, wasn't sure which to trust so I've mostly been using the hydrometer but that's a great point! I will look into it, thanks.

If you scroll about halfway down this page you will see Hydrometer Calibration. You can use that method to test your hydrometer out.

 

[agrazela]

You say you mash between 150 and 154°F. I'd say definitely get on controlling that mash temp more tightly. Based on my records, for me the difference between mashing (for 1 hour) at 150°F and 154°F is the difference between ~95% fermentability and ~84% fermentability (respectively)...that's a big difference, and could certainly account for the ~7 pts you unintentionally attenuated from your ~60 pt wort.

 

[LopeJuice]

You say you mash between 150 and 154°F. I'd say definitely get on controlling that mash temp more tightly. Based on my records, for me the difference between mashing (for 1 hour) at 150°F and 154°F is the difference between ~95% fermentability and ~84% fermentability (respectively)...that's a big difference, and could certainly account for the ~7 pts you unintentionally attenuated from your ~60 pt wort.

wow I had no idea it was that much of a difference. I know there are lots of other factors but is there a general chart somewhere that has fermentability vs mash temp? thank you for the post! This is definitely something I need to pay more attention to.

 

[Setesh]

wow I had no idea it was that much of a difference. I know there are lots of other factors but is there a general chart somewhere that has fermentability vs mash temp? thank you for the post! This is definitely something I need to pay more attention to.

How far down the rabbit hole do you want to go?

http://www.homebrewersassociation.o...pdf/2012/1616-04 Attenuation - Gregg Doss.pdf

 

[LopeJuice]

How far down the rabbit hole do you want to go?

http://www.homebrewersassociation.o...pdf/2012/1616-04 Attenuation - Gregg Doss.pdf

I've got some reading to do! thank you