Lager Yeast - What's More Important?

[lucas]

I'm brewing my first lager at the moment (using wyeast 2308) and have been able to keep the fermenter at a nice constant 14C inside a 100 can cooler. now i know i could drop that another few C with frozen bottles but am wondering if the benefit from the extra cooling will be outweighed by the more erradic temps?

lucas (who can't sleep, just got the lease on a new house with a huge shed... think of the brewing possibilities)

 

[mika]

Don't know about lagers, never tried to brew them, but Congrats on the new brewery

 

[Zwickel]

Hello lucas,

that yeast works well in a range from 9 to 13C.

14C might be a little too high, but I think youll not yet notice any strange taste.

In my experience, the Lager beer (Pilsener) tastes best if the fermentation runs at the lowest possible temperature, but in your case, I wouldnt change anything. Too much effort for a little effect.

Cheers

 

[Steve]

lucas - id be throwing in a couple of frozen 2 litre coke bottles into your cooler bag - try to get it down to about 10-12.
Cheers
Steve

 

[JasonY]

I wouldn't lose any sleep over 14degC, I have let lagers sit that high before and they have turned out fine. The ferment will be slightly faster but not drastically.

If your worried chuck another iceblock in there. Sure it will be fine

 

[devo]

14 deg C should not be a concern. Just so long as it dosn't shift around to much and sits around at a level temp.

 

[Weizguy]

IIRC, once you get to a ferment temp, it's better to keep it constant.

Even at higher temp, a lager yeast still produces a lager-like beer...and U ain't that far out of range.

The 2308 can be a bit tricky, I've read, and U might need a diacetyl rest. Best to research this online and taste along the way to get a feel for the process.

The 2308 is a nice yeast tho, even if I've only used it once. Maybe again soon...

Beerz
Seth out

 

[Dr Gonzo]

Lucas,
I am assuming you are measuring the temp external to the fermenter, one of those stick on strips perhaps?
Just a note for your future lagers that fermentation produces heat & the temp in the middle of the fermenter (which is what you should be aiming to maintain within the reccomended temps for the yeast strain) will be a few degrees higher than the surface temp during peak fermentation. 8 - 10 degrees would be a more desireable temp to maintain within your 100 can cooler if possible. But i wouldn't worry about it this time round. The worst the higher temp could do is produce some fruity esters.
Cheers
Dr Gonzo

 

[WillM]

Lucas

Pitch it at about 18C, once it starts fermenting, drop it to 12C and try to keep it there until about 1.020. At 1.020 let it warm up again for a few days before you Rack / lager / bottle it.

Here is what whitelabs say about pitching lager yeasts (www.whitelabs.com).


What temperature should I pitch a lager yeast?

There are two different methods of pitching lagers. Brewers use each method with success, but every brewer has their preference. The easiest method is (A).
A) Start the yeast warm and lower to 50-55F after the start of fermentation. The yeast should be pitched at 70 to 75 degrees Fahrenheit. Once you see active fermentation, bring the temperature of the wort down 10 degrees per 12 hours until the desired fermentation temperature has been achieved. This method works well without forming high amounts of esters because most esters are produced after the first 12 hours.
B) Pitch the yeast at the desired fermentation temperature (48-55 Degrees F). Lager yeast ferment well at this temperature, but they grow very slowly. If you are using this method, understand that you may not see signs of activity for 48-72 hours. If starting the fermentation cold, we recommend you make a 1-2 liter starter per 5 gallons, or if a commercial brewery, a starter 10% of the batch size.

 

[Jazman]

as i dont have a fermenaion fridge i have been using the steam beer yeast or a psuedo lager with a low temp ale yeast so that i get the lager profile in my beers with the slightly higher temp

 

[lucas]

thanks for the replies guys. I checked the temp this morning and its dropped to 13c naturally and stayed there all day. I'm going to leave it and hope it keeps dropping by itself as i figure the less rapid variations in temp the better

 

[Trough Lolly]

I'm brewing my first lager at the moment (using wyeast 2308) and have been able to keep the fermenter at a nice constant 14C inside a 100 can cooler. now i know i could drop that another few C with frozen bottles but am wondering if the benefit from the extra cooling will be outweighed by the more erradic temps?

lucas (who can't sleep, just got the lease on a new house with a huge shed... think of the brewing possibilities)

Hi lucas,
Out of curiosity, how big is the lager, SG-wise? Is it a pale or dark lager?

Wyeast 2308 (Munich Lager) has a reputation of being a bit of an unstable strain, but if this is fresh yeast and you used a decent sized starter, at least 1L of active yeast, it shouldn't be a problem. It may get a bit weird if you add a small starter of stressed 2308 and expect it to ferment cleanly and that's why I asked about the SG of the wort. 2308 is well known to produce plenty of sulphur at low temps, which to me is a good sign of proper lager fermentation with this strain. BTW, the sulphur is easily scrubbed out over time - and that's another good reason to lager the beer at around 1C for at least 2 months.

Brewing lagers at higher temps does raise the risk of adding esters to the beer, as has been pointed out, but the production of esters tends to peak late in the attenuative phase, after the growth or adaptive phase has concluded. This is one reason why there are many brewers who pitch the lager yeast at warm temps and then drag down the fermentation temp slowly over the first 48 hours, with no apparent ester presence in the finished beer.
Steve Alexander on the US based home brewing digest PM'd me some points on warm lager yeast pitching some time ago, and made a particular point that is worth noting/quoting:

My biggest concern is that the yeast can only form UFA lipids during the early aerobic period and they form less at higher temps. With less UFA the yeast may have stress problems (stuck fermentation, poor hi-grav performance) and will generally produce more fusels late than hi-UFA yeasts. ((The UFA he's referring to is Unsaturated Fatty Acids))

So, there are benefits to be had in getting strong aerobic growth happening in the early adaptive stage, but it's offset by lower UFA levels that may increase final fusel levels, even with a lower temp ferment, later on...
If I assume that the initial aerobic growth phase is over and the wort is actively attenuating, I'd agree with adding some more frozen bottles to get the temp down a few degrees.
The point about the difference in apparent temps on the outside of the fermenter, compared to the core temp is also worth noting. If you can, get a probe that you can immerse through an o-ring in the fermenter lid and you'll be working on a much more accurate actual wort temp reading.
Cheers,
TL

 

[lucas]

I'm brewing my first lager at the moment (using wyeast 2308) and have been able to keep the fermenter at a nice constant 14C inside a 100 can cooler. now i know i could drop that another few C with frozen bottles but am wondering if the benefit from the extra cooling will be outweighed by the more erradic temps?

lucas (who can't sleep, just got the lease on a new house with a huge shed... think of the brewing possibilities)

Hi lucas,
Out of curiosity, how big is the lager, SG-wise? Is it a pale or dark lager?

Wyeast 2308 (Munich Lager) has a reputation of being a bit of an unstable strain, but if this is fresh yeast and you used a decent sized starter, at least 1L of active yeast, it shouldn't be a problem. It may get a bit weird if you add a small starter of stressed 2308 and expect it to ferment cleanly and that's why I asked about the SG of the wort. 2308 is well known to produce plenty of sulphur at low temps, which to me is a good sign of proper lager fermentation with this strain. BTW, the sulphur is easily scrubbed out over time - and that's another good reason to lager the beer at around 1C for at least 2 months.

Brewing lagers at higher temps does raise the risk of adding esters to the beer, as has been pointed out, but the production of esters tends to peak late in the attenuative phase, after the growth or adaptive phase has concluded. This is one reason why there are many brewers who pitch the lager yeast at warm temps and then drag down the fermentation temp slowly over the first 48 hours, with no apparent ester presence in the finished beer.
Steve Alexander on the US based home brewing digest PM'd me some points on warm lager yeast pitching some time ago, and made a particular point that is worth noting/quoting:

My biggest concern is that the yeast can only form UFA lipids during the early aerobic period and they form less at higher temps. With less UFA the yeast may have stress problems (stuck fermentation, poor hi-grav performance) and will generally produce more fusels late than hi-UFA yeasts. ((The UFA he's referring to is Unsaturated Fatty Acids))

So, there are benefits to be had in getting strong aerobic growth happening in the early adaptive stage, but it's offset by lower UFA levels that may increase final fusel levels, even with a lower temp ferment, later on...
If I assume that the initial aerobic growth phase is over and the wort is actively attenuating, I'd agree with adding some more frozen bottles to get the temp down a few degrees.
The point about the difference in apparent temps on the outside of the fermenter, compared to the core temp is also worth noting. If you can, get a probe that you can immerse through an o-ring in the fermenter lid and you'll be working on a much more accurate actual wort temp reading.
Cheers,
TL

SG of the wort was 1075 and i pitched a 2L starter of yeast into it. definately getting the sulphur smell now, I'd be somewhat worried if i hadnt already heard about it. It doesnt smell too pleasant. I'm not sure I'll be able to lager it at quite such low temps, but i'll definately leave it outside in the cold for a good few weeks (or months if i have the self control) before i start drinking