Lager Fermentation Stalled At 1.015ish... What To Do?

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lukemarsh

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I made a Heineken style lager on the 10th of May and had it fermenting in my brew fridge at around 14 deg using frozen water bottles and a wet towel inside the turned off fridge. The OG was 1.045 and the airlock had been bubbling constantly for the past 10 or so days.

I did a hydrometer reading a few days ago and it was at about 1.020... I did another just now and it is at around 1.015 and the beer hasn't cleared up yet.
The airlock has completely stopped bubbling so I'm guessing it's stopped fermenting. I know you can't just go by the airlock, but it's gone from nonstop bubbling to dead silence with the water at the same level either side of the airlock (it's an S type airlock).

In the Brewing Crafts book (by Mike Rodgers-Wilson) it has the Heineken style lager recipe that I used (uses Brewcraft Dutch Lager kit + Brewcraft #60 German Lager kit converter + Saflager yeast and 22L final volume). In this recipe it says OG should be around 1.041 and the FG around 1.009.

Do I need to do anything to bring my FG down further? I'm just worried that I've gotten my OG reading wrong and therefore it still has more fermentation to go but has stalled (this tends to happen to my beers alot, they all stall at around 1.020 for some reason)...


Another thing is, I have 2 fermenters (one has a cider in it at the moment though)... should I consider secondary fermentation with this beer to make it clearer? I've never looked much into it so my knowledge of it is that basically you just drain the beer into another clean fermenter to get it off the yeast sediment at the bottom and allow the beer to clear... If I'm meant to do this, when is the best time? And what's the best way to do it?

Cheers!
 
The airlock has completely stopped bubbling so I'm guessing it's stopped fermenting. I know you can't just go by the airlock

Then why are you?

As fermentation approaches the end, it often slows down. A vigorous ferment might take a brew from 1070 to 1020 in 3 days then take another week or more to get to FG, depending on yeast just like when you heat a pot of water it takes minutes to get to 70/80 degrees and much longer to build up to 100. When you cool one down you can get it to 30 in as many minutes then take more than that just to drop the last few to 20.

1. Wait until you know it's actually stuck. The only way to know is checking gravity.
2. Gently swirl.
3. Allow to heat up. With a lager it's traditional to do a diacetyl rest anyway which will help drop the last few points. 1015 should be fine for this depending on expected FG
4. Rack to a separate fementer. Traditional for lagers anyway.
5. Wait and be patient between all of thesew. Lagers are slow but slow means clean.
 
My first thoughts are to leave it alone, it's probably not done yet Particularly as the yeast hasn't dropped out yet. How long has it been there?

Leave it in the primary for three weeks in total & check the gravity then. You may find that it may not get much lower anyway.

How much yeast did you pitch? When brewing a lager I find that two packets to a 23l batch is required. A bigger pitch of healthy yeast may help you get that extra couple of gravity points next time.

Stalled fermentations indicate that you haven't got enough good quality yeast to do the job. You may not be using enough, or your yeast may not be healthy due to poor storage or some other reason. Making sure your wort is oxygenated before pitching will also help this. If you are making a kit, pour your makeup water in from a distance above the fermenter so there is plenty of frothing of the wort. This will help in the yeast growth phase.

Have a read about secondary fermentation, there's plenty of history on that discussion which doesn't need to be repeated here. It's kind of like Holden vs Ford or Sunni vs Shia, people are on one side or the other and they won't ever agree. For the record, I'm in the no secondary camp so that's what I'd recommend.
 
Hahah I'm just a naive brewer who looks to the mighty bubble for fermentation signs... I also just hate to waste beer on doing bloody hydrometer readings all the time.

4. Rack to a separate fementer. Traditional for lagers anyway.

How do you do this? My friend who also brews said you could syphon it into the other fermenter, but that seems a bit difficult... would you just put the fermenter up on a table and have the other fermenter below it and drain the beer through the tap straight into the other fermenter? And when's a good time to do this? Should I wait until I know fermentation has stopped (say, a week) by checking gravity, then rack it and wait for it to clear up, then bottle?
 
Hey a South Aussie Docker fan LOVE the anchor go you Dockers

Yes gravity is youre friend but definately no splashing use some silicone hose coiled in the bottom & quitely transfer it
 
You need a hose (silicon or other food grade type hose) to minimise splashing. You can go tap straight into second fermenter which is how I do it but there is also a tap to tap method which minimises exposure of the beer to oxygen and potential infection. Look at the bottom of this article to read how it's done: http://www.aussiehomebrewer.com/forum/inde...;showarticle=68

A good time depends on why. I rack for secondary fermentation so that requires racking during actual fermentation - for me usually around 1020 or whatever is close to 3/4 the way to expected FG.

If you are just racking for clarity you can do that when FG is reached (not really a secondary fermentation - just using a secondary vessel)

If you are racking to kick off a stalled ferment, you do it when you know the brew is stalled and it hasn't responded to being swirled or warmed.

Basically for you it could be any time from now until the beer is finished depending on the whys. As GH has suggested you could also just leave it in the primary (presuming the ferment continues) although clear brightness is a hallmark of the style so lessening the yeast and other compounds making hazy or cloudy beer as much as possible with whatever means at hand is a reasonable course of action.
 
Hahah I'm just a naive brewer who looks to the mighty bubble for fermentation signs... I also just hate to waste beer on doing bloody hydrometer readings all the time.



How do you do this? My friend who also brews said you could syphon it into the other fermenter, but that seems a bit difficult... would you just put the fermenter up on a table and have the other fermenter below it and drain the beer through the tap straight into the other fermenter? And when's a good time to do this? Should I wait until I know fermentation has stopped (say, a week) by checking gravity, then rack it and wait for it to clear up, then bottle?

Yes, transfer from the primary fermenter to secondary fermenter through the tap. However, you will need to use some pvc tubing to the bottom of the secondary to avoid oxidation.

If you are doing an Ale this can be done after 5 - 7 days and a lager 10 -14 days, depending on the yeast you are using. If you are not inclined to rack to secondary (due to believe that this could cause infection or not having another fermenter) then adjuctation of the fermenter (washing machine type) will help you get to the final OG.

Don't forget tha lagering takes time.

Cheers Ken
 
As for warming up the beer to get the gravity down, how warm are we talking? I sort of forgot about the brew in the fridge and hadn't replaced the frozen bottle that was keeping it cold for the last few days, so when I checked it today it was at about 16 deg... When I bottle this beer I'm going to need to pick up the fermenter and move it inside which is going to shake it up alot. After this I wont be able to cool it down past 18 deg. Should I move the fermenter inside (after racking or not, depending what I decide to do) and let it settle for a few days to a week at 18 deg and then bottle? Will warming it up affect the taste much or only if it's still fermenting?
 
I also just hate to waste beer on doing bloody hydrometer readings all the time.

1. You're allowed to drink the samples.
2. You'll waste more beer with exploding bottles.
 
True! The samples aren't exactly great though... especially warm lager samples!
 
As for warming up the beer to get the gravity down, how warm are we talking? I sort of forgot about the brew in the fridge and hadn't replaced the frozen bottle that was keeping it cold for the last few days, so when I checked it today it was at about 16 deg... When I bottle this beer I'm going to need to pick up the fermenter and move it inside which is going to shake it up alot. After this I wont be able to cool it down past 18 deg. Should I move the fermenter inside (after racking or not, depending what I decide to do) and let it settle for a few days to a week at 18 deg and then bottle? Will warming it up affect the taste much or only if it's still fermenting?

if it's a lager, it's traditional to raise it to ale temps for a few days to allow any diacetyl to be cleaned up (yeast by-product that tastes/feels like butter/butterscotch/slick) then drop temp again to lagering temps ((not lager fermentation but below 4 degrees: closer to 0-1 is better). This cleans the brew right up and allows it to slowly mature, dropping yeast and other matter out of suspension. Essentially what lager means is to store cold so it's a major part of the process of making one. Some people bottle, allow to carbonate and then cold store. My impression/understanding is that larger volumes mature better than smaller and I prefer to do most of my maturation as a whole mass before priming and bottling. I'm a stickler for old traditions when I know they work and have a point (but only for how I approach things - your beer, your choice).
 
Hmm my only problem is raising and lowering temps means shifting the fermenter from a fridge outside to a cellar inside, so that'll shake up the sediment pretty well... Maybe if I rack it to secondary in about a week, leave in the cellar at 18 deg for a few days, then shift back to the fridge at <4 degrees for a while (week?) then shift again back to cellar to bottle?
 
Hmm my only problem is raising and lowering temps means shifting the fermenter from a fridge outside to a cellar inside

Why? Didn't you say in another thread you just bought a heat pad? My apologies if I'm thinking of someone else.
 
You sly bugger! Yeah that was me... christ I didn't even think of that! Kind of forgot I even had it, It's sitting underneath my cider at the moment...

To do this whole racking bizz I'd need to shift the fermenter though, because it's pretty low to the floor in the fridge. And I'd also need to shift it before bottling too because, as the fermenter is too low in the fridge, I can't fill the bottles up from the tap... I'll see if I can find a piece of wood or something that will hold the fermenter higher because the wire shelves look a bit on the weak side (hence why the fermenter's on the floor of the fridge)
 
Whatever method you choose to warm your brew up a tad I doubt you'll see too much negative effects from moving the fermenter about a bit. Just don't slosh it about so it gets aerated and you'll be alright. Stirring up the yeast cake now won't do anything terrible - it'll settle out again. In fact, since you suspect your beer has stopped early this will help get more yeast back in suspension and possibly fire the brew up again.
 
Alrighty I might leave it for a week until my cider is done then clean that fermenter out and rack the lager into it... then heat up in the fridge for a few days, and cool down again etc.

I don't suppose finings are out of the question here aswell? I have a few packets stored away somewhere... would they come in handy?
 
Saflager attenuates around 73%, currently your around 68%, so there is probably a bit to go.

My suggestions have largely been raised already:
- do a a diacetyl rest (ie warm it up for a few days) then cool back down
- swirl the yeast cake
- you could add more healthy yeast - but probably not worth it imho
- rack to secondary
- lager @ around 4 degrees for a few weeks after doing the above.

The other thing that I can't believe no-one has asked is have you corrected your hydrometer reading for the temp? Most hydrometers are calibrated to work at 20 degrees. If your wort is at 14, your actual gravity will not be what is indicated. Not by a lot mind you - your reading will be a point or 2 higher than what it really is.
 
The other thing that I can't believe no-one has asked is have you corrected your hydrometer reading for the temp? Most hydrometers are calibrated to work at 20 degrees. If your wort is at 14, your actual gravity will not be what is indicated. Not by a lot mind you - your reading will be a point or 2 higher than what it really is.


I'm fairly confident my OG reading was accurate because the temp was somewhere above 20 deg and below 25 deg (can't quite remember exactly), but the reading I took the other day I'm not entirely positive... I took the sample and left it for a few minutes, probably no more than ten minutes, so it may have been too cool. I'll do another reading later in the week and make sure to leave it for ten mins at least, and see if it has changed.
 
There's some great advice in this thread, but if you followed it all you'd be buzzing around like a blue arsed fly bouncing temperatures and changing vessels. I say SLOW DOWN! It's been in there less than two weeks!
Now is a good time to raise the temp a few degrees for a diacetyl rest. Just stop swapping out the ice bottles or keep the fridge door open tbut it sounds like you already got it to 16. Then leave it alone for a few days before you check your SG.

At that point decide whether to bottle then lager, lager then bottle, crash chill then lager then bottle bla bla...if you want to keep it simple...bottle when it's finished fermenting, after two weeks in bottles at room temp crash chill them to -1C for 3 days then lager at serving temp for as long as you can keep your paws off.

I have used this method successfully, it's simple and quicker than secondary-CC-lager-more yeast-bottle maturation. My last lager was best after 3days at -1C then 10 days at 4C...very light colour, crystal clear with no finings and it was delicious. I'm also of the 'no secondary' school of thought, and the Keep It Simple Stupid university ;)
 
I made a Heineken style lager

the Heineken style lager recipe that I used (uses Brewcraft Dutch Lager kit + Brewcraft #60 German Lager kit converter


Saflager attenuates around 73%, currently your around 68%, so there is probably a bit to go.


Nothing re AA% on the Fermentis site, only this:
This bottom fermenting yeast is originating from the VLB (Berlin) in Germany and is known under the code RH. The strain is used by Western European commercial breweries and has been reported to produce lagers with some fruity and estery notes. Sedimentation: high. Final gravity: medium.

So he has made a beer using "Body Enhanser" and pitched half the required amount of a yeast with Medium attenuation qualities which has ceased fermentation at 1.015.

1.045 - 1.015 / 1.045 = 66% Apparent Attenuation

Am I the only one who is not surprised ????

Screwy
 

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