Stuck…or not?

The Homebrew Forum

Help Support The Homebrew Forum:

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

Seghes

Active Member
Supporting Member
Joined
Jul 18, 2020
Messages
89
Reaction score
33
Location
Southampton UK
My first brew after a disastrous winter/spring of flooding in my cellar brew area was intended as a reward for “getting back on my horse” after months of absence and the clear up. A Fullers ESB clone was mashed at 67C (1hr then boiled for 1hr). Lallemand London English Style yeast(12g) pitched at 24C which took off for 4 days going from OG 1.064 to stopping at 1.028 where it looks properly stuck for 3 days now. I have tried swirling the FV, adding yeast nutrient, and adding 25g of Youngs Dried Active Yeast, (yup probably a mistake), raising the FV temp from 21 to 23C, all to no avail. The wort looks clear but has a sweet, immature taste, checked when I did a hydrometer reading. Brewfather shows attenuation 55% ABV 4.7%. FG is intended to be 1.018.
Having now read around the subject, I am assuming more yeast is not the answer and the only useful information I can find is to add some drops of ALPHA-AMYLASE to lower the sweetness and high SG.
Another mistake which will make the beer too dry? Any alternative solution? Or should I just leave it, ignoring my assumption it is definitely stuck?
 

Attachments

  • IMG_2693.jpeg
    IMG_2693.jpeg
    38 KB · Views: 5
Hi
I’m no expert but I believe that Lallemond suggest mashing at slightly lower temperatures than 67°c as London yeast does not utilise the sugar maltotroise which is produced at higher mash temperatures. Have you used this yeast before?
I’ve only used it once and found that I stopped short of my predicted final gravity and whilst the beer a Bass clone had a full body it was on the sweet side.
 
What is the actual attenuation of this yeast as it just says medium attenuation on the sites I looked at?
Also this yeast is sold re-packaged by some sellers is it the genuine article?
 
Being still newish at all this, I haven’t used this yeast before. I place my faith, as always in the excellent Malt Miller where I got it. The packet certainly looks the real deal! It was marked Exp Jul 2023 but was pitched on 17 Aug - surely this isn’t the problem, as it was very active for 4 days before it stopped?
 
Being still newish at all this, I haven’t used this yeast before. I place my faith, as always in the excellent Malt Miller where I got it. The packet certainly looks the real deal! It was marked Exp Jul 2023 but was pitched on 17 Aug - surely this isn’t the problem, as it was very active for 4 days before it stopped?
If it's from MM it will be real athumb..
 
This may be part of the answer as Mash Monster has said.
This is a lift from the Lallemand site re this yeast
LalBrew London does not utilize the sugar maltotriose (a molecule composed of 3 glucose units).
Maltotriose is present in wort in an average 10-15% of all malt worts. The result will be fuller body and residual sweetness in beer. Be advised to adjust gravities and mash temperatures according
to desired result.
Edit
It definitely does say that attenuation is medium which means it will not ferment as low as most yeasts especially if you have a reasonably SG in the 60's plus the lack of fermenting Maltotriose.
Maybe introduce another yeast of the same stylish or and with ALPHA-AMYLASE. it may ferment down dry but if you are unable to drink a sweeter than normal beer at least it will be drinkable.
Ps this is to be seen as a good learning process and not a negative
 
Last edited:
Being still newish at all this, I haven’t used this yeast before. I place my faith, as always in the excellent Malt Miller where I got it. The packet certainly looks the real deal! It was marked Exp Jul 2023 but was pitched on 17 Aug - surely this isn’t the problem, as it was very active for 4 days before it stopped?
How was the yeast stored? It’s viability may have been compromised. Which in effect could mean you had inadvertently under pitched which could have caused it to stop short.
 
I wonder what range of values "medium attenuation" covers? I normally think of "high" as anything above 72% so guess "medium" would be in the 60s. Plugging your figures you've currently got 56% attentuation, which feels a bit low, so suspect as above that mashing temp was a factor.

It's probably a combination of the two, mash temp a bit too high and a medium attenuating yeast. I also wonder if the temp was too high too, if you pitched at 24C a few more degrees would have been generated during initial fermentation. I usually pitch no higher than 21C.
 
My first brew after a disastrous winter/spring of flooding in my cellar brew area was intended as a reward for “getting back on my horse” after months of absence and the clear up. A Fullers ESB clone was mashed at 67C (1hr then boiled for 1hr). Lallemand London English Style yeast(12g) pitched at 24C which took off for 4 days going from OG 1.064 to stopping at 1.028 where it looks properly stuck for 3 days now. I have tried swirling the FV, adding yeast nutrient, and adding 25g of Youngs Dried Active Yeast, (yup probably a mistake), raising the FV temp from 21 to 23C, all to no avail. The wort looks clear but has a sweet, immature taste, checked when I did a hydrometer reading. Brewfather shows attenuation 55% ABV 4.7%. FG is intended to be 1.018.
Having now read around the subject, I am assuming more yeast is not the answer and the only useful information I can find is to add some drops of ALPHA-AMYLASE to lower the sweetness and high SG.
Another mistake which will make the beer too dry? Any alternative solution? Or should I just leave it, ignoring my assumption it is definitely stuck?
Which MM kit was it they sell several ?
 
I wonder what range of values "medium attenuation" covers? I normally think of "high" as anything above 72% so guess "medium" would be in the 60s. Plugging your figures you've currently got 56% attentuation, which feels a bit low, so suspect as above that mashing temp was a factor.

It's probably a combination of the two, mash temp a bit too high and a medium attenuating yeast. I also wonder if the temp was too high too, if you pitched at 24C a few more degrees would have been generated during initial fermentation. I usually pitch no higher than 21C.
Tricky this cos following the recipe for a “normal” 67C seems so predictable. Seems that a study of yeast characteristics is the only alternative! Never done that having always trusted the recipe (from MM)
 
Tricky this cos following the recipe for a “normal” 67C seems so predictable.

Know what you mean, 66/67C seems to be standard. However, I tend to mash low these days, around 64C. I know you should be able to mash both high and low but it depends on your kit, fine if you have once of these fancy computerised things controlling the temp but I do BIAB and I found mashing high could end up with the temp creeping up just a bit too high. Like you I had a few finished with higher OGs than expected. Since mashing lower I haven't had this.
 
I always store my yeast in the fridge it stays a lot fresher that way. This could be part of your trouble coupled with it being out of date. It’s just a suggestion
Me thinks this will have contributed to a low attenuating yeast which has gone a long way to the result
 
Know what you mean, 66/67C seems to be standard. However, I tend to mash low these days, around 64C. I know you should be able to mash both high and low but it depends on your kit, fine if you have once of these fancy computerised things controlling the temp but I do BIAB and I found mashing high could end up with the temp creeping up just a bit too high. Like you I had a few finished with higher OGs than expected. Since mashing lower I haven't had this.
Ha ha! I have one of the “fancy computerised” set ups - in my case the Grainfather G40 with full app control. Since I bought it, have yet to do a successful brew - but I’m mostly to blame with daft errors. I’m interested in your lower mash temp and will look into it. After all the GF40 will do as it’s bloody told - even though I might be elsewhere with my feet up.
 

Latest posts

Back
Top