Fermentation went from 100 to zero -- LalBrew London Yeast

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Knoah

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I am making Whitys Gon Fishing Pale Ale from Joy of Homebrewing. I used LalBrew london yeast. 1 packet rehydrated.

In controlled fermentation chamber @ 70F ---- I forgot to get a OG......

Made it Sunday night.
Monday night the fermenter was actively swirling and airlock was at a steady pace.
Tuesday morning and night no visible activity. No airlock bubbles or and swirling has stopped. Picture from Wednesday morning .

My guesses would

  1. Bad seal on lid - however there was lots of bubbling Monday -- so maybe not.
  2. The fermentation slowed waaaay down and is not producing CO2 that much
  3. One thing i noticed after I looked up the yeast is that
    1. 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.
    2. Not sure if that means anything, probably the finished result will have less alcohol
I am going let it keep fermenting for another week or so and try it out. I just thought the scenario was odd.
 

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A bad seal would explain why bubbling stopped, but not the lack of visible activity in the fermenter. It's probably either (mostly) finished or stuck.
 
How long have you spent sitting by the airlock watching it? When I use London, it has one nice highly active period, but then like you said; slows waaay down.
 
How long have you spent sitting by the airlock watching it? When I use London, it has one nice highly active period, but then like you said; slows waaay down.



according to the title of the thread, it sounds like it's pretty much done fermenting?
 
Should have said visible fermentation activity went from 100% to zero. That is all I meant. I have not done a gravity reading since it has been it fermenter.



then i agree with you, give it a couple more days. i'd just wait till the top was glass, being it's in a clear fermenter..
 
The recipe calls for an OG of 1.046 and since this is an extract beer, it will be very close to that. It is expected to have a FG of 1.014 ( a reasonable number) so it won't be a strong nor a strongly flavored beer. Yes it could have stopped visible fermentation in only a couple days, especially if fermented warm. If I were brewing this beer I would check the FG at day 10 and again on day 12 and if they matched I would bottle it. Then I would give the beer about 2 to 3 weeks in the bottle to mature. It would make a good "lawnmower beer".
 
Should have said visible fermentation activity went from 100% to zero. That is all I meant. I have not done a gravity reading since it has been it fermenter.
It's hard to see activity in beer once the short lived kraeusen is over.. You have to look real close. And if you are at the age you need readers or beyond then you have to give yourself a few moments to let your eyes focus properly.

Then you might see some tiny bubbles and yeast/trub swirling around in the FV.... If it's a clear plastic or glass FV.

Don't worry about bubbles in the airlock. I haven't seen the first bubble in mine for at least three brews. Yet my SG goes from the expected OG to the FG as indicated by my hydrometer.

So don't trust the visual signs. Check your SG with a hydrometer or refractometer. It's about the only way you can be assured if something happened or not.
 
I've never used Lalbrew London but I've read here that there's a recommendation to use two packs in the typical neipa batch - which I expect means around a 70 point brew. 116-something points would be half again bigger than that.

Anyway, when I use London III I pitch ~350B cells per 5.5 gallons, start it at 66°F, oxygenate with O2 .5lpm for 4 minutes through a .5 micron air stone, bring the temperature up to 69-70°F by the fourth day post-pitch, and let it run there to finish up a 14 day fermentation. This usually brings my typical 75 point neipa batch down to the mid to upper teens...

Cheers!
 
OG is 1.046. 1.116 is the pre-boil gravity, which is not something that's making a whole lot of sense to me for an extract recipe.
This recipe is intended to be a concentrated boil with top off water. That is why the pre-boil gravity is so high. When you top it off you dilute it to about 1.046.
 
Given you have a glass fermenter, when you start to see the top layer clearing it's a pretty good indication the yeast is floccing and dropping out because it isn't active. You could bump up the temp a few degrees for a diacetyl rest and then let the temp fall and that clearing will be obvious. Then it's pretty much ready for packaging.
 
I use Lallemand London often and my best guess is it’s just done fermenting already. London is typically a quick fermenting strain and routinely finishes within 48-72hrs for me, depending on the OG. I raise the temperature on day 2 or 3 post pitch to help clean up any off flavors (English yeast tend to produce more diacetyl than other strains and they flocculate out faster leaving less time to clean up any off flavors so it’s always good to employ a diacetyl rest when using one) and I’ll let it sit for a few more days then bottle it or cold crash and keg it. If your primary fermentation temperature was indeed 70f then your need for a diacetyl rest is much lower since at those temperatures yeast clean up after themselves pretty well.

The other thing I want to touch on is the information you found about London not being able to ferment maltotriose. To put it simply that just means there are complex sugars in the beer that the yeast will not consume and will carry over into the finished product. These left over sugars will sweeten the beer (to an extent) and increase the body/mouthfeel and FG of the beer. All of this is in relation to the yeasts attenuation range - basically it is the limit on how much sugars the yeast can consume to produce alcohol. You will see this as a numbered percentage, for reference Londons listed attenuation range is 65-72%, so that means it tends to ferment 65-72% of the available sugars in the wort. I say tends because there are ways to manipulate this up or down (adjunct grains or sugar, malt selection, mash temperature, water to grist ratio) but these are more advanced, all grain techniques. If you’re reading The Joy of Homebrewing and brewing up those extract recipes I’m going to assume you’re a new brewer (welcome to the hobby!) so all of this information might be going over your head right now. As you learn and grow as a brewer these things will start making more sense to you and eventually you’ll be able to plan and adjust entire recipes around these facts, there are many “tools in the tool box” as they say around here!
 
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OP said "forgot to get a OG" so I assumed that he does have a means of doing this.
I tend to think forgetting to take the OG on an extract batch with top off water is a good thing as adding the top off often leads to inaccurate measurement and frustration. Since the sugars in extract are known, taking the recipe's expected OG as what you got is a good practice.
 
I tend to think forgetting to take the OG on an extract batch with top off water is a good thing as adding the top off often leads to inaccurate measurement and frustration. Since the sugars in extract are known, taking the recipe's expected OG as what you got is a good practice.
I do have hydrometer, i just forgot to take a sample. I did not use method of small concentrated boil with water top off. I did everything in 10 gallon kettle. Started with 6.5 gallons and ended around 5 gallons of wort. But your advice in that scenario makes sense to me.
 
I'm really starting to think that your beer just fermented fast and you don't have an actual problem here. You're coming up on a week. I would check the gravity on Monday or Tuesday and again on Thursday or Friday. In the meantime, RDWHAHB (especially since this is a Papazian recipe).
 
I do have hydrometer, i just forgot to take a sample. I did not use method of small concentrated boil with water top off. I did everything in 10 gallon kettle. Started with 6.5 gallons and ended around 5 gallons of wort. But your advice in that scenario makes sense to me.
There really is no need to take an OG sample on an extract beer. If you got 5 gallons or wort, the OG will be 1.046 or very close to it because that is how the recipe is made. It's only when you do all grain that the OG is important as you won't know how efficient your system is at converting starch to sugar and how efficiently you can recover the sugars.
 
If you have a decent way of getting a sample from the FV without opening the lid, then take a hydrometer or refractometer reading. Otherwise just be patient and let the FV sit for at least the full time recommended by the recipe.

Me... I'd wait for the beer in the FV to clear before I even considered taking a SG reading or bottling it. However when the beer does clear up, then it likely reached it's FG long before then.
 
When brewing extract batches, measuring SG would confirm that the volume of wort is appropriate and that all the fermentable ingredients were added.

With full volume boils, this is easy to do.

With partial volume boils, there may not be a single approach for accurately measuring SG all possible partial volume approaches.
 
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