First lager - need for diacetyl rest?

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Reedy

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Now that I have a temp controlled fermentation fridge, I thought I'd try an actual lager yeast. To that end, I've giveb the Coopers Czech Pilsner recipe a go;

1.7kg TC Pilsner
1kg light dried malt
25gm saaz pellets (steeped in 500ml boiled watee for 15mins & added to FV)
W-34/70 + kit yeast
Made to 20L
OG 1.045 (expecting FG 1.011)

Pitched at 24c as per instruction, and brought down to 12c within 24 hours.

It's been in the FV for a week now, and I am wondering;
(1) is a diacetyl rest necessary for a K&K recipe?
(2) if so, when should I increase the temperature & by how much?

Most of what I have read on AHB with regard to diacetyl seems to be in relation to AG.
 
Its the yeast that creates the diacetyl not the fact that its AG or K&K, i would do one when the gravity is about 80% done, i like to raise a few deg a day till its at ale temps then let it sit for a few days.
 
I usually do a rest at 16 degrees where the beer has been fermenting at 12 degrees. Leviathan is on the money with attenuation. So when the beer has dropped to about 1.020 then increase the temp. If you look up "forced diacetyl test" then you will understand if you need to do one or not.
 
On Thursday night there was a "Craft Lager" night at Foghorn here in Newcastle, presenting Beers were the brewers from Foghorn, Potters (Hunter Valley Brewing Company), Hope Estate and the Lovedale brewery at the Crown Plaza.
They all talked about their beer and how they brewed it, and participated in a pretty frank Q&A, they all did a Diacetyl Rest, but then again they are all under commercial pressure to move their beer through the plant as fast as they can.
Read a good text book on lager brewing like Kunze and a Diacetyl Rest is referred to as a remedial process for beer that has too high a level of Diacetyl, but they spend a lot longer in process than is the norm in small craft breweries - trade-off's

Personal opinion is if you are 1/ in a hurry, 2/ have a Diacetyl problem 3/ don't want the beer hogging the fridge for 120 days it might be worth thinking about.
If on the other hand you pitch a massive amount of yeast into a really well made and aerated wort, control your temperature and do the ramp from fermenting to lagering nice and slowly (~0.5oC/day) and are willing to wait and wait and w... Its possible you will make beer that is just too dam good to share.

So I guess most of us will be doing a Diacetyl rest them wont we!
Mark
 
you have an ale yeast and a lager yeast, why did you leave the kit yeast in ?
 
Thanks for the advice guys. Just took a quick sample, SG is 1.016, and none of the tastes I have read about associated with diacetyl.

I've increased the fridge temp to 16 and will leave it there until SG is stable (will then be cold crashing for 10-14 days).

Mxd - the Thomas Coopers Pilsner comes with a lager yeast
 
MHB said:
On Thursday night there was a "Craft Lager" night at Foghorn here in Newcastle, presenting Beers were the brewers from Foghorn, Potters (Hunter Valley Brewing Company), Hope Estate and the Lovedale brewery at the Crown Plaza.
They all talked about their beer and how they brewed it, and participated in a pretty frank Q&A, they all did a Diacetyl Rest, but then again they are all under commercial pressure to move their beer through the plant as fast as they can.
Read a good text book on lager brewing like Kunze and a Diacetyl Rest is referred to as a remedial process for beer that has too high a level of Diacetyl, but they spend a lot longer in process than is the norm in small craft breweries - trade-off's

Personal opinion is if you are 1/ in a hurry, 2/ have a Diacetyl problem 3/ don't want the beer hogging the fridge for 120 days it might be worth thinking about.
If on the other hand you pitch a massive amount of yeast into a really well made and aerated wort, control your temperature and do the ramp from fermenting to lagering nice and slowly (~0.5oC/day) and are willing to wait and wait and w... Its possible you will make beer that is just too dam good to share.

So I guess most of us will be doing a Diacetyl rest them wont we!
Mark

When you say 'pitch a massive amount of yeast', what do you actually mean by that? Do you mean pitch the 'ideal' amount of yeast which is widely accepted as being 1,000,000 x mL x Plato x 1.5 or is it something other than that?

I haven't brewed many lagers but I often read people saying do a certain volume starter, pitch a massive amount of yeast etc but that doesn't really mean anything to me.

How much yeast should I be pitching for a lager? I've always followed the widely accepted normal lager pitch rate which is around the 400 billion cells for a 20L wort of about 1.050. Is this enough?
 
Well Budvar (the Czech brewer) reportedly pitch the equivalent of around 64 fresh Wyeast smack-packs into 20L of beer - is that massive enough for you?
6.4EXP12 really is way past the high end of the "recommended" range but they get primary over in 3 days at 8oC and make pretty dam good beer.
That is a lot more than the normally stated 1-1.65EXP6 cells/mL/oP, for the 20L of 1.050 (12.5oP) the answer is 2.5EXP11 - 4.12EXP11.

Given good brewing conditions and well aerated quality wort 400 Billion will work and if you are pitching that sort of volume you should be well on the way to making good lager, I am a little suspicions of some of the numbers people think they are pitching, even more suspicious of the output from some of the yeast pitch calculators on line that people are trusting.
Mark
 
I just keeged a bo-pils fermented with Mangrove Jack M84 at 12-13C. There was detectable diacetyl so I raised temp to 18C for a few days. Diacetyl was absent and f.g. was reached so I fined with gelatin in the FV and CC'd for a few days.

Now, here's my query. I primed the keg with dextrose and it's currently sitting at ambient to carbonate. I will then CC again for a few weeks before serving.

Could I have skipped the d-rest as the carbonation for a week would've have performed the same task?
 
Diacetyl may not be noticable at bottling or kegging, it can take a few weeks to appear and then be very apparent. Some people don't seem to notice it in small amounts, I personally hate it at any amount. Having said this I find raising the temperture of a lager/pilsner to around 18 for 24 hours completley rids Diacetyl, I do this then crash chill.

Batz
 
MHB said:
Well Budvar (the Czech brewer) reportedly pitch the equivalent of around 64 fresh Wyeast smack-packs into 20L of beer - is that massive enough for you?
6.4EXP12 really is way past the high end of the "recommended" range but they get primary over in 3 days at 8oC and make pretty dam good beer.
That is a lot more than the normally stated 1-1.65EXP6 cells/mL/oP, for the 20L of 1.050 (12.5oP) the answer is 2.5EXP11 - 4.12EXP11.

Given good brewing conditions and well aerated quality wort 400 Billion will work and if you are pitching that sort of volume you should be well on the way to making good lager, I am a little suspicions of some of the numbers people think they are pitching, even more suspicious of the output from some of the yeast pitch calculators on line that people are trusting.
Mark
Ok great, that gives me a better idea of what other people / professional brewers are doing. I may experiment by doubling my pitch rate to around the 800B yeast for my batches of lager to see the affect it has on both quality of fermentation and time.

Cheers.
 
Do you pitch at fermentation temp? If not, try that. I pitch at around 6-8 and let rise a little, 8-10. Works great for me
 
On Saturday I suddenly found time to keg the lager and decided to pitch the next cube onto the yeast cake (at around 25C, but didn't think of it at the time). I jumped at the chance, as anything beer related gets seriously frowned upon here. Anyhow, the krausen was climbing out of the FV after 10hrs and it took at least 30hrs to get it down to 13C. I decided to check the SG this arvo and it was 1.011, down from 1.050. Tastes good too so I'm going to let it sit at 18C for a couple of days and go from there.

I was worried that the warm pitch would affect the flavour but I think from sheer numbers I might get away with it. Hydro sample tastes quite clean, much cleaner than the brew that was kegged just before it. I realise Batz mentioned diacetyl creeping in later. We'll see.

Also, it would be nice to see some blokes be less arrogant on here. Not everyone has multiple FVs or fridges or lots of time to brew beer. Some of us might cut corners out of necessity and compromise with other responsibilities. It'd be nice to see some of you lighten up a bit.
 
I have pitched lager yeast and then chilled to lager fermenting tempertures many times, in fact most times. I bet with your diacetyl rest you'll be OK. Diacetyl is formed by several brewing practices, and a diacetyl rest will not cure all, just have a google.

Also, it would be nice to see some blokes be less arrogant on here. Not everyone has multiple FVs or fridges or lots of time to brew beer. Some of us might cut corners out of necessity and compromise with other responsibilities. It'd be nice to see some of you lighten up a bit.
We have 37,322 members on this site now, was less than 150 when I joined. :unsure: Put that many people together and your going to find a few you may not like a hell of a lot. Sometimes you need to pass over a post or two.
Good luck with your lager.

Batz
 
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