High FG

[Endatheworld]

Brewed this recipe for the Winter months. Was the first time doing a high gravity beer. The Beer finished quite a bit above the expected FG. It was supposed to be 1019 but finished at 1026. I am pretty sure it had finsihed fermenting but I had it bottled before I took the FG.

Any ideas why this happened? Is 1026 very high to bottle at? Like i said I only every brew Pale ales and Lagers so have never had anything with this high of FG.

Type: All Grain
Batch Size: 20.00 l
Boil Size: 33.29 l
Boil Time: 120 min
End of Boil Vol: 24.74 l
Final Bottling Vol: 17.16 l

6000.00 g Pale Malt, Maris Otter (5.9 EBC) Grain 2 85.7 %
250.00 g Amber Malt (43.3 EBC) Grain 3 3.6 %
225.00 g Caramel/Crystal Malt - 60L (118.2 EBC) Grain 4 3.2 %
225.00 g Chocolate Malt (689.5 EBC) Grain 5 3.2 %
50.00 g Roasted Barley (591.0 EBC) Grain 6 0.7 %
250.00 g Brown Sugar, Dark (98.5 EBC) Sugar 7 3.6 %
40.00 g Magnum [12.00 %] - Boil 60.0 min Hop 8 47.7 IBUs
28.00 g Liberty [4.30 %] - Steep/Whirlpool 0.0 min Hop 15 0.0 IBUs
1.0 pkg British Ale Yeast (Wyeast Labs #1098) [0.12 l] Yeast 16 -

Original Gravity: 1.081 SG
Final Gravity: 1.027 SG
Alcohol by Vol: 7.3 %
Bitterness: 54.3 IBUs
Est Color: 43.2 EBC

[Will_D]

When it comes to bottling:

If the yeast has finished fermenting (as in no bubbles and constant gravity) then its finished fermenting.

Why?

a: There may be not be any unfermentable sugars left in which case priming with new sugars and the existing yeast will condition the beers

b: There are still fermentable sugars but the yeast has given up due to alcohol stress/lack of nutrients. In this case repitch with a HA yeast

c: Any takers??

[Greg2013]

The cold ambient temps recently could also be a factor,my last 4 brews all finished at 1020 and the highest OG was 1077.

[Will_D]

The cold ambient temps recently could also be a factor,my last 4 brews all finished at 1020 and the highest OG was 1077.

Greg, In winter Hi grav beers need to be kept warm. Waht temp are you fermenting at?

Remember the auld adage: Brew your lagers in Winter and winter beers in spring/summer 

[molc]

I was going to suggest max attenuation, but that was all within range of that yeast. Was there a starter? If it was stressed, it might just have crapped out early due to the high alcohol ennvironment.

[Simon_]

What was the mash temp?

[Endatheworld]

When it comes to bottling:

If the yeast has finished fermenting (as in no bubbles and constant gravity) then its finished fermenting.

Why?

a: There may be not be any unfermentable sugars left in which case priming with new sugars and the existing yeast will condition the beers

b: There are still fermentable sugars but the yeast has given up due to alcohol stress/lack of nutrients. In this case repitch with a HA yeast

c: Any takers??

Thanks Will. I wont be able to reptich now as it is in bottles! Tasted it last night and its surprisingly good. I was a bit worried that I had over did the Bitterness at 54 IBU but glad did now as it balances the sweetness nicely.

The cold ambient temps recently could also be a factor,my last 4 brews all finished at 1020 and the highest OG was 1077.

The temp should not have been a problem as I fermented in my temp controlled freezer at 18C. Maybe I should of fermented it at 20 or 21 as 18c is at the low end for Wyeast 1098.

I was going to suggest max attenuation, but that was all within range of that yeast. Was there a starter? If it was stressed, it might just have crapped out early due to the high alcohol environment.

Yes, i made a 2L starter and the yeast has a Alcohol Tolerance of  10% ABV.

What was the mash temp?

Mashed at 67c for 60 mins.

[nigel_c]

Do a quick check on your thermometer. It may be off. Calibrate it by putting it in boiling water. If it's off you'll know. You may of mashed a lot higher than you thought if it's off which would explain the high FG.

[mcgrath]

Do a quick check on your thermometer. It may be off. Calibrate it by putting it in boiling water. If it's off you'll know. You may of mashed a lot higher than you thought if it's off which would explain the high FG.

Thats good info. I was using a thermometer that was reading 2degC high for two years..

[Endatheworld]

Do a quick check on your thermometer. It may be off. Calibrate it by putting it in boiling water. If it's off you'll know. You may of mashed a lot higher than you thought if it's off which would explain the high FG.

Thats good info. I was using a thermometer that was reading 2degC high for two years..

Good advice alright Nigel_c ....which is why i always use a second thermometer to check the Mash Temp. I use one of those Floating Mash Thermometers and a digital pen thermometer. I suppose both of them could be off? I might just check them to be sure.  Would love to be able to rely on just one. Anybody got any good recommendations? I was thinking of buying one of these www.thermapen.co.uk a few months ago but £57 seemed a bit much?

[Alex Lawes]

Mash temp and time is likely the culprit. You're mostly only getting alpha amylase at that temp which will leave behind more dextrin. Do a longer mash at around 64 then bring it up a step to finish it up. If you're doing a HG the alcohol and glycerol production from the yeast gives you a lot of the mouthfeel of bigger beers so you don't always have to leave behind a load of dextrin but it's up to your preference. This video explains mash dynamics very well. Hope it helps.
http://youtu.be/1PSvCRtVdZU

[Endatheworld]

Mash temp and time is likely the culprit. You're mostly only getting alpha amylase at that temp which will leave behind more dextrin. Do a longer mash at around 64 then bring it up a step to finish it up. If you're doing a HG the alcohol and glycerol production from the yeast gives you a lot of the mouthfeel of bigger beers so you don't always have to leave behind a load of dextrin but it's up to your preference. This video explains mash dynamics very well. Hope it helps.
http://youtu.be/1PSvCRtVdZU

Cheers Alex. Great video. Best explanation I have seen on Mashing.

Think you are right about the Mash Temp being on the high side it would of never got below 68c and could well of been closer to 70c. I recently started using an converted Igloo Cooler and noticed that it doesn't lose any temp over the hour compared to my old Cooler which would drop 2 or 3 degrees.

I really must invest in a new decent thermometer as I checked all 4 of mine  last night and they all reading different temps.

[biertourist]

I agree with the post with the video  of Bobby in it. 

I was initially really planning to blame yeast health given the high OG, but I'd agree that you prIobably just mashed too high for this beer.
The diastatic power of Marris Otter can really vary fairly dramatically, too and sometimes it gets surprisingly low and when you combine MO basemalt with a large percentage of specialty malts you really want to calculate the total diastatic power of the mash and then adjust the time and temp of your mash accordingly.

At 67-68C, you're at the high-end of the mash temp range and you ARE going to end up with a less fermentable mash; I'd also agree with what everyone else is saying about double-checking your thermometer because above 68-68 you're getting into denaturing risk.  Also whether you combine your malt with your water or your water with your malt matters.  -If you add the water to your mashtun first and then add the grain to it the first bits of grain will come in WAAY over 67C and will be almost the same temp as your strike water and you'll denature those enzymes very quickly the middle of the dough-in grain will still be well above your target temp and only the final bit of grain that's added will never go above 67-68.

This why you want to add water to your grain.  Then the grain never gets into the enzyme denauring temps.  This is especially important with Marris Otter basemalt and even more so when you have lots of speciality malts in the grist, too.


P.S. That particular Bobby video is one of the best on the interwebs; I just can't get enough of it.


Adam

[Endatheworld]

I'd also agree with what everyone else is saying about double-checking your thermometer because above 68-68 you're getting into denaturing risk.  Also whether you combine your malt with your water or your water with your malt matters.  -If you add the water to your mashtun first and then add the grain to it the first bits of grain will come in WAAY over 67C and will be almost the same temp as your strike water and you'll denature those enzymes very quickly the middle of the dough-in grain will still be well above your target temp and only the final bit of grain that's added will never go above 67-68.

Interesting as I have only ever added the grain to the water. I never thought of it that way but I can see your point. It has been a interesting lesson making this high gravity beer. I have done dozens of Lagers and Pale ales and never had any of these issues but then again I am so used to the recipes/methods I brew that I have got them pretty much down at this stage.

Thanks everybody for your insights, as usual its been informative!