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D-rest/lager Fermentation Question

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GalBrew

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Hi all,
I am currently fermenting my first lager and there seems to be quite a few different opinions on what exactly to do around here.
I have a bo pills fermenting with s-189 at 12deg, which started off at 1.050. When it got down to 1.013, which only took 6 days I gave it a 2 day D-rest at 18 deg, which I got from the Yeast book (there is no taste of diacetyl in the beer). In that time it has gone down to 1.004 which is a tad lower than expected. Now I am not sure what to do, do I go back down to 12deg for another week and then keg and lager or should I keg now and lager? Not exactly sure what to do?

cheers,
:beer:
 

micblair

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That's over 90% attenuation - unless that's in the range specified for that strain you could have a wild yeast/bacterial infection? Are you absolutely certain that 1.050 was your OG?
 

micblair

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That's over 90% attenuation - unless that's in the range specified for that strain you could have a wild yeast/bacterial infection? Are you absolutely certain that 1.050 was your OG?

Sorry I didn't answer your question, I would cold crash/lager immediately. Don't waste any time dropping the temp 1 degree per day either. Hopefully this should arrest any further attenuation if there is any??
 

mxd

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Hi all,
I am currently fermenting my first lager and there seems to be quite a few different opinions on what exactly to do around here.
I have a bo pills fermenting with s-189 at 12deg, which started off at 1.050. When it got down to 1.013, which only took 6 days I gave it a 2 day D-rest at 18 deg, which I got from the Yeast book (there is no taste of diacetyl in the beer). In that time it has gone down to 1.004 which is a tad lower than expected. Now I am not sure what to do, do I go back down to 12deg for another week and then keg and lager or should I keg now and lager? Not exactly sure what to do?

cheers,
:beer:
how are you taking you gravity ?

That is far too low, so it would appear (if gravity is true) that you have an infection or you SG was not 1.050

is WH wheelers hill ?
 

GalBrew

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Well, looks like my refractometer is now disagreeing with my hydro. Hydro reads 1.018 (which would make more sense) and now refract says 5.8 brix which is 1.006 corrected on BS2. So an even better question is what do I do now? Obviously my d-rest was way too early as the beer is not fermented out yet. Should I keep it at 18 or drop back down to 12 to finish?
 

GalBrew

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how are you taking you gravity ?

That is far too low, so it would appear (if gravity is true) that you have an infection or you SG was not 1.050

is WH wheelers hill ?
See my above post re: gravity. Probably a good idea to check with the hydro. It is not infected, it actually looks and tastes quite good.
Looks like my refrac needs to be recalibrated.

And yes WS is Wheelers Hill, although I haved moved from there now.
 

mxd

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leave it at 18 or drop it down to 16,

when it's at final 1.012 or whatever then chill it down to 0ish for a few days, keg it and lager it in the keg for a few weeks.
 

mxd

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when using refacto for fermenting beer you need to enter SG to get current G, did you do that ?

Ignore that, I did the calc.
 

labels

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There are a few ways of making lagers

I think the diacetyl rest does more than rid possible diacetyl. Raising to 18C thorougly finishes fermentation and helps with other fermenation by-products, acetaldehyde for example. I raise to 18C until the kraussen has completely fallen. Some yeast strains produce more diacetyl than others.

Although a lot of people recommend crash cooling, I do not. The yeast will immediately go into hibernation which is not what you want for lagering. It is the yeast that lagers the beer, doing a final clean-up of left over fermentation by-products. Drop the yeast out and you lose a lot of the lagering potential of yeast. Dropping the temperature slowly allows the yeast to aclimatise to the gradual lower temperatures so it's still working, doing it's job of lagering which is your goal.

After the 18C rest, you can drop the temperature back to 12C or even 10C quickly but I recommend then to drop by 1C per day. Then hold at -2C for 3 days at least for the beer to clear.

I make lagers almost exclusively and they all turn out crystal clear with an ultra-clean flavour profile - after many years of practice mind you, and I can not think of a better way to ferment lagers other than what I have outined above. However, I am always ready to listen to other people's techniques and learn new things.
 

GalBrew

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Ok, so after a good degas of the beer my hydrometer reads 1.010 which is more realistic (refrac is still 5.8 brix/1.006 though). So I guess its off to the keg for lagering.
 

Amber Fluid

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Not that I do any lagers but someone (professional) once told me if you don't have diacetyl problems, or can't taste it, then there is no need for a D-rest.




I don't seem to get diacetyl issues so have never done a D-rest and things seem to taste fine, ie. no hint of diacetyl.
 

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Cant use a refractometer as soon as it has alcohol in it. Only for wort.

Beer will not taste of VDK. You let the beer warm u to force the precursor of VDK alpha-acidactelate. This is heat liable and converts to VDK with heat if present. The yeast has a high affinity for VDK's and will suck them in if present, but if there is an excess of the precursor or maturation is not handled properly the obvious happens.

Standard is to get 1.004-8 off the expected terminal gravity and let it free rise.

scotty
 

Helles

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D-rest @1.020 until finished
Keg and Crash Chill
Works for me
 

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