How Low Can Lager Go?

[AussieJosh]

Hey guys got a Coopers Pils in the fridge with the Coopers Lager yeast that comes with it also a packet of s-23, its been in there since Tuesday night put the yeasts in at 27c, 12 hours later it was at 18c, 8 hours after that it was 9c and has been there ever since, the krausen is only maybe about half a cm high, have not taken a reading yet. anyway how low can these yeasts go and still ferment?

Cheers!

Josh.

 

[Nick JD]

S23 is fine at 9C. I wouldn't go much lower though.

 

[AussieJosh]

Cheers Nick! You are my Beer God!

 

[mxd]

if you put it in at 27 make your you do a D-Rest towards the end.

 

[raul777]

what would be a good temp to start a larger / pils

 

[AussieJosh]

sorry if this is a stupid question, im always learning have been brewing for a few years and done only two AG in the past few weeks but.........what is D-rest?.... Days rest? and what is exactly the meaning of this? and why if started at 27? I know 27 is not ideal for larger.....there is a little temp instruction on the S-23 regarding putting the yeast in in the 20's and the teens..........sorry for all the questions.......i just want to learn as much as i can so i can be the best brewer i can be.

 

[bignath]

sorry if this is a stupid question, im always learning have been brewing for a few years and done only two AG in the past few weeks but.........what is D-rest?.... Days rest? and what is exactly the meaning of this? and why if started at 27? I know 27 is not ideal for larger.....there is a little temp instruction on the S-23 regarding putting the yeast in in the 20's and the teens..........sorry for all the questions.......i just want to learn as much as i can so i can be the best brewer i can be.

Hi Aussie Josh,

D-rest is "Diacetyl Rest". It's the process where by you raise the temp of your fermenting beer to allow the yeast to eat up the "off flavours" (diacetyl being one of them) that can sometimes be produced by a warm ferment in the first few days of fermentation.

I usually do mine (if i am going to do one, as sometimes i don't bother) when the beer is nearly at FG. For me, that's usually around day 7 or 8. I bring the temp up of the fermentation to around 20 degrees. I mostly brew ales, and my standard ferment temp is 18 degrees. Some people do a "D Rest" when the fermentation gets to 1.020, others do them after a certain period of days, others don't bother at all.
I would say that it's a process more important for lager brewing though, as you would generally want very clean tasting beers, and diacetyl can hide somewhat behind the flavours in an ale.

From memory, i think diacetyl is picked up by most people as a slight (or obvious if it's a real bad case) butterscotch taste, and can also have a "slippery" mouth feel.

Cheers,

Bignath

 

[Bribie G]

According to Chris White's new yeast book, if you started a fermentation at say 20 degrees then dropped it down for the balance of the primary fermentation, then you should go back up to that 20 for the diacetyl rest.

 

[BjornJ]

I've read of warm pitching before, that you can pitch at 18-20 degrees and "wait until signs of fermentation" before dropping the temp.
But how long to wait?
Do you pitch at say 18 and set the fridge to 12 so it will drop over night, or wait until the next morning before changing the fridge temp so it will be not until that night before it reaches 12 degrees?



Bjorn

 

[Nick JD]

But how long to wait?

With most of the dry and a couple of the liquid lager yeasts I pitch in the mid-twenties and then put it in the fridge set to 12C. The development of the initial stages of krausen happens about the same time as the 20L has chilled to about 16C, and about 4 hours later when the krausen is at its peak the ferment is at 12C.

I don't have any diacetyl issues - but I have had fruitiness from S23 before (and don't use it now). S189 is superclean using this method. So is 34/70 if you can wade through the sulphur.

The only exception to this I've had was with 2001. That stuff is a tortoise.

Wyeast recommends yeast kept in the 20s for the anaerobic phase. I think it helps build a desirable population size without using two packs.

 

[BjornJ]

Hi Nick,
thanks for that.
S-189 is the one I want to try this with, after my so-so result at 17 degrees.

So pitch at room temp and leave it to cool down overnight should be enough time for it to get a good start, by the sound of it.

thanks
Bjorn

 

[Trusty1]

Cheers Nick! You are my Beer God!

Hey josh - does PB know about this?