Significantly lower FG than expected

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

rpolzin25

Well-Known Member
Joined
Nov 5, 2015
Messages
106
Reaction score
6
Location
Greenville
So i just brewed a belgian dark strong ale recipe that i came up w/ myself a week ago. Initial gravity was 1.091 and per brewing software it was expected to finish about 1.020 (I was expecting more like 1.015 given the amount of candi sugar I used). So I decided to take a sample and check gravity since there was zero airlock activity and the final gravity was 1.005. I used a triple scale hydrometer so it should be fairly accurate and was sitting at a temp of 70 degrees (hydrometer set for 68 degrees). This seems way too low given what I would have been expecting. It fermented at mid 60s during the most active part of fermentation.

Here is the grain bill.
Mashed at 152 F for 60 minutes w/ Batch sparge
12 lbs Belgian Pilsner
3.5 lbs Belgian Pale
0.5 lbs Special B
0.5 lbs belgian Caramunich
0.5 lbs german munich
1 lb belgian candi syrup D90 added at end of the boil
1 lb belgian candi syrup d45 added at high krausen
1 lb belgian candi syrup golden added 24 hours after d45 added

I used mangrove jacks m41 yeast and pitched 2 packets which were rehydrated.

At the end of the boil my OG was 1.079 so i am somewhat guessing what my OG is since only 1/3 of the belgian candi sugar was added before fermentation.

Is this what I should expect for this beer? Thanks

Hydrometer reading.jpg
 
I'm corncerned about this beer. An FG that low could mean an infection.

I tasted it. It tasted fine aside from being a little hot from the sample being only 7 days after start of fermentation. Overall though it didn't smell bad or taste infected. Nor did it look infected. That would be 94% attenuation and I was reading online that i could expect mid 80s for attenuation.
 
If it looks, smells and tastes good, you're good. The low gravity isn't common but considering the high volume of sugars, healthy yeast will keep growing and working in the right conditions.
 
For a Belgian you want high attenuation. I know with dubbels, brewers shoot for mid 80s to low 90s. I tend to always get higher attenuation. Possibly raise mash temps next time.
 
So I went to bottle tonight. Figures I wouldn't have enough bottle caps so I just transferred to a secondary. I decided to take a sample (it sat in the primary, a speidel fermenter, for 4 weeks) and low and behold the fg was at 1.002. This means I am looking at 11.7% abv. I tasted it and I think it may actually be a dumper...it has a strong alcoholic/medicine like flavor so I am guessing it must have gotten infected. It actually tasted worse than the first time I tried it at 1 week of fermentation.
 
So I went to bottle tonight. Figures I wouldn't have enough bottle caps so I just transferred to a secondary. I decided to take a sample (it sat in the primary, a speidel fermenter, for 4 weeks) and low and behold the fg was at 1.002. This means I am looking at 11.7% abv. I tasted it and I think it may actually be a dumper...it has a strong alcoholic/medicine like flavor so I am guessing it must have gotten infected. It actually tasted worse than the first time I tried it at 1 week of fermentation.

Check the gravity in a few days and if it stays the same, bottle it. Leave it in the bottles for 3 to 6 months before sampling again. If it is still bad tasting in 6 months you have my permission to dump it but I'd probably leave it for at least a year just to be sure it won't come around before I'd dump. High gravity beers take a long time to tame down so don't be in a hurry to dump what might become a stellar trippel.:rockin:
 
Check the gravity in a few days and if it stays the same, bottle it. Leave it in the bottles for 3 to 6 months before sampling again. If it is still bad tasting in 6 months you have my permission to dump it but I'd probably leave it for at least a year just to be sure it won't come around before I'd dump. High gravity beers take a long time to tame down so don't be in a hurry to dump what might become a stellar trippel.:rockin:

I think you might be missing the fact that this beer finished at 1.002, not 1.02...i got 98% attenuation. I don't think that is going to correct with time.
 
I think you might be missing the fact that this beer finished at 1.002, not 1.02...i got 98% attenuation. I don't think that is going to correct with time.

It may not correct in time...but in 6 months you'll know, not just guess. You'll tie up $25 worth of bottles for 6 months and get them all back if you do have to dump. Pretty small risk. How much different is a Belgian ale yeast from a saison yeast? I had one batch done with Belle Saison that ended at 0.997. That's even lower than your FG and it took 6 months for it to come around. The next one I did like that ended at 1.005 and wasn't as good. The yeast you used does say very high attenuation.:rockin::mug:
 
I agree with RM-MN. Tasting a high gravity Belgian that early can be misleading. Bottle it up and forget about it for at least 5-6 months and report back. Belgians can take a lot of time to mellow and develop their true flavor. High gravity beers can take even longer.
 
Well I have it sitting in a secondary right now so when i get the chance to get some more caps I may as well bottle it then. Thanks for the advice.
 
Are you sure you mashed at 152 for 60 minutes. Mashing even a bit lower would result in way more fermentable sugars and would result in a really dry beer, especially with all that candi syrup.

For example this guy http://brulosophy.com/2015/10/12/the-mash-high-vs-low-temperature-exbeeriment-results/ did a low temp mash and a high temp mash with the exact same recipe and ended up with .009 SG difference.

That is why i prefer to step mash. I have a lot more control about how the beer will turn out.

If I want it dry i'll go for a longer period on lower temperatures if i want body i leave it on 145 for like 5 minutes before going to 158 for the rest of the time.
 
Well I have it sitting in a secondary right now so when i get the chance to get some more caps I may as well bottle it then. Thanks for the advice.

Take your time getting the bottle caps. I'd suggest about a month or 2. Maybe even 3 if you have the patience. :rockin:
 
I am definitely positive I mashed at 152. I was shooting for 150 and screwed up by overheating my strike water. So it was at 152 at start of mash and was still about 152 when I measured mash temp after 60 minutes. I also stirred about halfway through and temp was maintained. The main thing I did w/ this recipe that i think helped the yeast go nuts is I added the candi sugar in steps w/ 1/3 end of boil, 1/3 at high krausen and 1/3 24 hours later.
 
I too say bottle it. I have done a couple of high gravity beers that were not very good early and came into their own at 6 months or so. One I drank now and then for over 3 years.
 
Back
Top