Stout fermentation

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jonnyjarman

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Hey, new member here and new to AG brewing, hope you guys can help.
I brewed a stout on Sunday hopefully in time for xmas and fermentation has seemed to stop. SG was 1.055 and target is 1.018... It has currently been at 1.033 for the last 2 days and not much activity within the beer. I have it at 18 degrees and used S-04 yeast which I have never used before. What can I do to get it going again? Heat pad under the fermenter? Pitch another sachet of yeast? Hope someone can help!!!!
 

darrellm

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S-04 can struggle a bit at the lower end of the temp range, especially with dark beers (there's a recent thread on this, my last one finished high). Getting the temp up should help, I normally aim for 20C with S-04.
 

jonnyjarman

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Cheers guys. Will get the heat mat out and get it wrapped up. Think a fermentation fridge may be on the xmas list!!!
 

jonnyjarman

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What was your recipe?
Crisp Maris Otter (3700 grams)
Weyermann® CaraRed® (220 grams)
Weyermann® CaraMunich® Type 2 (170 grams)
Weyermann® Carafa Special® Type 3 (160 grams)
Crisp Chocolate Malt (140 grams)
Crisp Roasted Barley (36 grams)
TMM Jumbo Oat Flakes 26 (240 grams)
Fuggles Pellets (39 grams)
SafAle™ S-04 11.5g (1 packs)
Lactose 500g (1 packs)

Method
Beer Style (main): British Ales
Beer Style (sub): Sweet Stout or Cream Stout
Batch Size: 20L
Original Gravity: 1.056
Final Gravity: 1.018
ABV %: 5
IBU: 21

THE MASH
Temperature °C: 67
Length (mins): 60
Out temp °C: 75
Out time (mins): 10

THE BOIL
Boil time (mins): 60

Additions and timing:

5g Ground Coffee Beans – these should be added to the either the mash or boil.

60 mins Fuggles. 20g
30 mins. Fuggles. 12g
30 mins. Vanilla Pod. 4.5g (not included)
15 mins Organic Chocolate. 7.5g (not included)
15 mins Lactose. 150g

Secondary additions and timing:

N/A

Yeast: S-04 English Ale Yeast
Fermentation temperature/steps: Pitch at 18c, leave temperature to free rise. Cap at 21c until fermentation is complete
 

jonnyjarman

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I would give it a gentle swirl and increase the heat up to 20. See if you can get it going again
Still stuck at 1.033 after another 3 days of upping the temp from 18 to 20/22. Will a pitch another packet of yeast?
 

jonnyjarman

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S-04 can struggle a bit at the lower end of the temp range, especially with dark beers (there's a recent thread on this, my last one finished high). Getting the temp up should help, I normally aim for 20C with S-04.
Still stuck at 1.033.....
 

foxy

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Started 70 and hummed around there and by the end of the mash it was 66
That is your problem right there, the higher your temperature the less fermentability,
better to start low for the first half of the mash then raise the temperature.
 

terrym

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Still stuck at 1.033.....
Try this
 

jonnyjarman

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That is your problem right there, the higher your temperature the less fermentability,
better to start low for the first half of the mash then raise the temperature.
Cheers mate, will keep that in mind next time
 

jonnyjarman

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Try this
Cheers - think I might try the sugar method and see if we get anywhere. If not I will pitch another packet of yeast on monday/tuesday. We live and learn
 

Portreath

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I can agree with the temp issue, if I've gone up to 67c mashing stouts I,ve had a few stick at around 1.020., so I keep it lower now.
 

Doublediamond

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I can agree with the temp issue, if I've gone up to 67c mashing stouts I,ve had a few stick at around 1.020., so I keep it lower now.
Interesting. Why is it for stouts in particular that you keep mash temps down, is it the darker grains that are problematic?
 
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foxy

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Interesting. Why is it stouts in particular that you keep mash temps down, is it the darker grains that are problematic?
Good question, adding malts like chocolate, roast, some crystal, you are adding unfermentable sugars. Though the sugars are soluble they are unfermentable giving you a higher final gravity, the main reason I suspect of so many folk complaining of a stalled ferment.
Two ways to get around this, cold steep or hot steep those grains, filter and add to the boil, my preferred method perform mash out at 77 C for 15 minutes adding the above grains at the start of mashout.
Makes salt additions a lot easier, makes for a smoother tasting beer and largely decreases any chance of astringency from the roasted grains.
 

jonnyjarman

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Still stuck at 1.033 after a week... I re pitched the least, added 100g of dissolved sugar to the mix and even carefully changed fermenting vessels to see if that did anything. It is stuck at around 2.8% so think I will have to get rid of the lot. Thinking my temp regulation at the mash and being unable to get a full rolling boil was the downfall here for some reason... might have to buy a gas burner rather than using my induction hob for my 35L malt miller pot. thanks for the help guys
 

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