ABV 20% below estimate, add more yeast or bottle?

FreddieFred

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Hi all.
I am onto my third brew, a strong Belgian ale. The fermenting stopped after a week, with a final gravity giving an ABV of about 20% less than I estimated it should from all the grain I poured in :). Online calculator I used reckoned a 7.39% brew and I'm currently stuck on 5.78%
Should I pitch another packet of yeast - I used 1 packet of Fermentis Safbrew S-33 for a 23 litre brew - or should I just bottle and enjoy?
 
A week is not enough time for fermentation. You need to be sure that it is done before you bottle it. I would leave it for at least one more week and check again. You are referencing ABV, are you taking gravity readings? What was your OG, what is your expected FG?
 
Craigerrr is right.
At only one week it probably isn't done (unless you used Kveik yeast).
Take another gravity reading in 2-3 days and see if it is the same or if the yeast is still working at the more complex sugars.
If it is the same in 2-3 days then we can start talking about why it didn't finish as expected. We'll need the recipe for that and some notes on your process (mash temps, mash thickness, malt and yeast used) so jot it down if you don't have the recipe and brewday snapshot saved here.
 
Hi and thanks. I should have said its now two weeks the brew has been in the fermenter. I did a gravity reading Monday and today and it hasn't changed at 1.018 though I swirled the fermenter every day. The Original Gravity was 1.062 which was below where I calculated it should have been, I don't know if that effects it?
I had a stuck fermentation, at an undrinkable level, on my first brew because the wort temperature was too high when I pitched the yeast and possibly because the yeast hadn't been refrigerated. I rescued this by pitching another packet of yeast and the beer turned out OK but not great. I'm thinking another packet of yeast might spoil the taste somewhat plus I want to get on with my next brew after. :)
 
What yeast are you using? Some yeast strains finish up at 1.018
 
OG will affect it. Were you using the recipe tools here? I found myself missing OG until I got the efficiency right, once the kit was dialled in I started hitting my numbers consistently.

Stirring the fermenter every day seems like an unusual approach? Also, are you able to control the temp accurately? I find bumping the temp up over a few days when I think it's finished gives me a bit more confidence that we're all done. Had diacetyl flavours once and it was awful, don't want to go there again.
 
Hi and thanks. I should have said its now two weeks the brew has been in the fermenter. I did a gravity reading Monday and today and it hasn't changed at 1.018 though I swirled the fermenter every day. The Original Gravity was 1.062 which was below where I calculated it should have been, I don't know if that effects it?
I had a stuck fermentation, at an undrinkable level, on my first brew because the wort temperature was too high when I pitched the yeast and possibly because the yeast hadn't been refrigerated. I rescued this by pitching another packet of yeast and the beer turned out OK but not great. I'm thinking another packet of yeast might spoil the taste somewhat plus I want to get on with my next brew after. :)
Okay. More than likely it is done - especially since you tested Monday and yesterday. That is a 4 day period with no change... At 1.062 you underpitched it if you only added one pack (two packs would have been better - probably 3 if you were going to be over 1.072). If you were using extract then I am not too surprised. Have you tasted it? While carbonation definitely changes things, you can get some sense of what the finished product will be. I recommend bottling it this weekend while your next batch is brewing.

If you definitely want it to be lower (or taste less sweet) than you do possibly have a few options... If you like the results well enough and are ready to move on then bottle it or give it another week and then bottle. Patience is hard but well worth it. Sampling and giving some notes on the taste can also help us guide you further.

Can you give us the following:
1. Yeast strain (Nottingham, US-05, US-04, Belgian Abbaye) -
2. What type of beer?
3. Recipe info. like base grains, specialty grains, extracts etc. (even name the kit if you used one)
4. Procedure (as much as you can remember) - This is More important if you were brewing via all-grain...
 
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You're having an apparent attenuation of 71% which is within the stated range of your chosen yeast strain (68 to 72%).
 
Thanks for the replies. Brewed on a Grainfather:
6kg Pilsner malt
1kg CaraBelge Malt
500g Candy Sugar
Cardinal Hops
Coriander Seeds
1 packet Fermentis Safbrew S-33 yeast.
Mashed at 75C for 90 minutes
Boiled for 90 minutes.

Fermented at 21-23 Celsius

I was going for a strong Belgian type ale, I'm worried that if I bottle now it will be very sweet? I drank my hydrometer sample and it seemed OK ... .
 
Is that mash temp normal for the style?

Edit: Wondering about fermentation temp as well?
 
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s-23 is a lager yeast and will not really give you a belgian beer... However, you may be closer than you think considering your high mash temp and your your high fermentation temp...

1. s-23 is best used under 60 F (15C) but can make a "clean" beer at higher temps... Like you did... If you wanted a belgian shoot for Abbaye yeast (it can be obtained in a dry version too - think pears in the finish)...
2. A mash temp of 167 F (75C) will result in a sweeter beer especially if you mash in at less than 1.75 Pound per gallon...
3. If you want a dryer beer then shoot for 152 (66c) or lower. ------ Once you hit 67C then you are stepping into a different range that make for a sweeter beer.
4. Certainly bottle what you have and call it something closer to a "bock"....

Feel free to share a recipe before brewing if you want to make sure you hit the target.

- - Good news: You definitely have beer! AND - you may be closer to a belgian that you thought!
 
Hi all.
I am onto my third brew, a strong Belgian ale. The fermenting stopped after a week, with a final gravity giving an ABV of about 20% less than I estimated it should from all the grain I poured in :). Online calculator I used reckoned a 7.39% brew and I'm currently stuck on 5.78%
Should I pitch another packet of yeast - I used 1 packet of Fermentis Safbrew S-33 for a 23 litre brew - or should I just bottle and enjoy?
S-33 is notorious for high final gravity. And contrary to what most people think it is not a Belgian yeast.
 
SORRY! I just realized you wrote S-33 and NOT S-23... What Steve said is true about that yeast.

so my #1 should have read something more like:
If you want a neutral ale yeast, US-05 and Notthingham are solid choices. There are several others too.

If you want a belgian yeast then try Llemand's (or Lalbrew) Abbaye yeast. There are other yeast too - more so in the liquid form.
I just used Abbaye on a Bock recipe and MAN it totally changed that beer! It tastes Belgian - lots of fruit - mostly pears.

#2,3 and 4 still stand! :)
 
Thanks for the help guys. Learning things with every brew. Any recommendations on the amount of priming sugar I should use with this brew? I'm leaning on using a calculation based on 2.4 volumes of CO2 because my last brew seems a bit underprimed.
 
S-33 is notorious for high final gravity. And contrary to what most people think it is not a Belgian yeast.
Yes, that.
Here's what can happen, though...It'll go like crazy and stop within a few days at maybe 70% attenation and if you leave it long enough at high temp, it can restart and drop much further and create a little spice and fruit along the way.
It's not great for typical Belgian beers but I have used it to create a Belgian Pale (a style with a less yeast-forward flavor profile) that's won multiple awards.
I've used it for a Hazy Pale that was simply supurb. I've used it in conjunction with S-23 Lager yeast for my Cream Ale, Pre-Prohibition Porter and an Octoberfest it it works wonders for flavor and mouthfeel.
 
Yes, that.
Here's what can happen, though...It'll go like crazy and stop within a few days at maybe 70% attenation and if you leave it long enough at high temp, it can restart and drop much further and create a little spice and fruit along the way.
It's not great for typical Belgian beers but I have used it to create a Belgian Pale (a style with a less yeast-forward flavor profile) that's won multiple awards.
I've used it for a Hazy Pale that was simply supurb. I've used it in conjunction with S-23 Lager yeast for my Cream Ale, Pre-Prohibition Porter and an Octoberfest it it works wonders for flavor and mouthfeel.
This is really good info J A! Thanks.
 
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Should have added this before, but the beer turned out really terrific! :) If I'd paid a £10 for six bottles of this I'd be really chuffed.
Tips from this, don't sweat the FG and trust the priming calculator.
Now's a good time to post a pic! - Unless it is already gone of course! Did you get the desired results from the yeast? I am assuming you bottled it mid MAY time-frame? - No over-carb issues?
 

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