Help please - high FG

[Nick Pead]

Hi all,

Thanks in advamce for any advice.

Brewed an old ale 2 weeks ago, which all went very well. Expected OG was met at 1.066, but FG is stubbornly refusing to come down from 1.027, was hoping for 1.016.

Recipe included 200g of black treacle and the only slight problem with the brew was that my target mash temp of 68.5 was exceeded (probably started at 72C).

Two packs od dried yeast were used and ferment got off to a rapid start. Have been rousing the yeast over the last few days by swirling the bucket and temp raised to 23C, but nothing has changed.

What to do next?

 

[Zambi]

Welcome!
How did you measure your FG?
If refractometer, did you use one of the tables that compensates for the presence of alcohol?

 

[Nick Pead]

No, we use a hydrometer

 

[Megary]

What yeast did you use? Some English strains are notorious for starting quick and finishing quicker. As an example, if you used Windsor (a yeast that doesn’t eat maltotriose), then 60% attenuation might be all you get.

 

[dmtaylor]

What strain of yeast was used? Some English yeast strains such as Windsor, Munton's, and M15 are unable to eat a malt sugar called maltotriose and as a result can only attenuate to about 60% which is exactly what you are seeing. The fermentation might be finished if you used any of these common yeasts. However you could add a different yeast such as S-04, US-05, or Nottingham to eat more sugars, it will just take an extra week or so.

 

[Minbari]

Hi all,

Thanks in advamce for any advice.

Brewed an old ale 2 weeks ago, which all went very well. Expected OG was met at 1.066, but FG is stubbornly refusing to come down from 1.027, was hoping for 1.016.

Recipe included 200g of black treacle and the only slight problem with the brew was that my target mash temp of 68.5 was exceeded (probably started at 72C).

Two packs od dried yeast were used and ferment got off to a rapid start. Have been rousing the yeast over the last few days by swirling the bucket and temp raised to 23C, but nothing has changed.

What to do next?

That was prolly your issue. High mash temp killed beta and alpha enzymes making it less fermentable.

 

[Nick Pead]

I used WHC Bond yeast
https://whclab.com/product/bond-dried-yeast/?v=79cba1185463

Supposed to have attenuation rate of 76-80%.

I used a thicker mash than normal (I'm probably a bit too liquid normally) of 2.7L/kg and the higher mash temp will have created some extra unfermentables. I'm not sure if the treacle left some as well.

Do you think these fine margins are enough to make that much difference from what was expected.

Do you reckon it's time to cold crash and then bottle?

 

[dmtaylor]

Oh, I didn't notice the high mash temperature. Yeah you likely killed your enzymes. Even so, you could try adding US-05 for the best odds at fermenting out some extra sugars. Or just live with it and bottler 'er up as-is. Your decision.

 

[Nick Pead]

Many thanks all.

My professional brewer friend was in attendance on the day, and when I noticed the high mash temp, I suggested adding some cold water. He said not to bother, so I will be having some stern words with him.

 

[Donoroto]

Many thanks all.

My professional brewer friend was in attendance on the day, and when I noticed the high mash temp, I suggested adding some cold water. He said not to bother, so I will be having some stern words with him.

Go easy on him Nick. After all, it is beer. But sometimes I get poor attenuation and, honestly, I can't figure why. So I just take it as a session beer and go on.

 

[WesBrew]

To add on, You still made beer and it’s probably pretty good. Take notes, nail it next time around.

 

[Sandy Feet]

161 for a Mash temp? Yup, that is pretty damn high.
I thought they had a strike water calculator on this site, but I didn't see it when I just looked. They do have an infusion tool, but I didn't see the actual calculator for getting an actual strike water temp.
That is very helpful.

 

[Donoroto]

161 for a Mash temp? Yup, that is pretty damn high.
I thought they had a strike water calculator on this site, but I didn't see it when I just looked. They do have an infusion tool, but I didn't see the actual calculator for getting an actual strike water temp.
That is very helpful.

There is, it is part of the recipe builder.

 

[Brew4Mark]

Hey Nick, I have been brewing for almost 20 years now and I have had some of the same issues. However, lately I have been experimenting with an enzyme called glucoamylase. you can purchase it on Amazon. I like to add it to my Mash and i keep that at 142F. Then when cooling with the chiller, i stop at 140 and add a bit more then let rest for 15 min and continue cooling to 78F. I usually reach my desired OG and set aside to ferment. I use white labs wlp090. My final gravities have been running between 1.004 and 1.008 I know this sound low but the beer has been turning out amazing.

 

[Sandy Feet]

1.004-1.008. For a Saison yes. For a Brut IPA yes. Some of the lagers show 1.008 for FG, but how many other styles would you want below 1.008?

 

[Bigbre04]

Many thanks all.

My professional brewer friend was in attendance on the day, and when I noticed the high mash temp, I suggested adding some cold water. He said not to bother, so I will be having some stern words with him.

depending on how long it was at that temp, the damage could have already been done.

At the end of the day it is beer, if you dont like it give it to your friends!

 

[Minbari]

Hey Nick, I have been brewing for almost 20 years now and I have had some of the same issues. However, lately I have been experimenting with an enzyme called glucoamylase. you can purchase it on Amazon. I like to add it to my Mash and i keep that at 142F. Then when cooling with the chiller, i stop at 140 and add a bit more then let rest for 15 min and continue cooling to 78F. I usually reach my desired OG and set aside to ferment. I use white labs wlp090. My final gravities have been running between 1.004 and 1.008 I know this sound low but the beer has been turning out amazing.

I use that and alpha. Have seen about a 5-10% efficiency bump.

The glucose will function up to about 158F, so if you keep it under 155F, you are good. Alpha dies about 146F

 

[Bigbre04]

I use that and alpha. Have seen about a 5-10% efficiency bump.

The glucose will function up to about 158F, so if you keep it under 155F, you are good. Alpha dies about 146F

Damn it yall this makes me want to buy enzymes. I have been ignoring that voice for months now, but here it is back again!

 

[GFHomebrew]

Hey Nick, I have been brewing for almost 20 years now and I have had some of the same issues. However, lately I have been experimenting with an enzyme called glucoamylase. you can purchase it on Amazon. I like to add it to my Mash and i keep that at 142F. Then when cooling with the chiller, i stop at 140 and add a bit more then let rest for 15 min and continue cooling to 78F. I usually reach my desired OG and set aside to ferment. I use white labs wlp090. My final gravities have been running between 1.004 and 1.008 I know this sound low but the beer has been turning out amazing.

Have you tried adding it to the fermenter?

I've been using it for 2 brews just in the mash.
I'm scared that if I add the Gluco-amylase into the fermenter it'll ferment untill 1.000 and the beer taste like carbonated water...

 

[Minbari]

Have you tried adding it to the fermenter?

I've been using it for 2 brews just in the mash.
I'm scared that if I add the Gluco-amylase into the fermenter it'll ferment untill 1.000 and the beer taste like carbonated water...

I would be willing to bet it would do nothing. That enzyme needs heat to wake up and it converts starch to sugar. I don't see a use in the fermenter