Lagering

[Stuster]

I was hoping somebody could direct me to some technical articles on the effects of lagering. I know the reasons often given for lagering, but I'm fairly unimpressed by the rationale given by anything I've managed to turn up so far. For example, Palmer just says

A common question is, "If the beer will lager faster at higher temperatures, why would anyone lager at the low temperature?" Two reasons: first, in the days before refrigeration when lager beers were developed, icehouses were the common storage method - it's tradition. Second, the colder lagering temperatures seem to produce a smoother beer than warmer temperatures. This would seem to be due to the additional precipitation and settling of extraneous proteins (like chill haze) and tannins that occur at lower temperatures.

My emphasis.

And from BYO

For the homebrewer there are three goals of the lagering process:
1.To allow yeast, haze-forming proteins, and any other suspended materials to drop out of the beer.
2.To improve and mellow the flavor of the beer.
3.To carbonate the beer.

Well, materials will drop out with time, cold or not. Carbonation will happen, cold or not. The only thing is it 'seems to' mellow the flavour. I'd like to know why (if h34r: ) this is happening. Any references would be much appreciated. Also, if anybody has done an experiment to split a batch and lager half/not lager the other half, that'd be very interesting too.

 

[WildaYeast]

Hi Stuster,

I have a copy of Dave Miller's Homebrewing Guide. Was the first book I picked up -- it was out on a sale table. Not a beginning book, but has been a good reference.

Chapter 21, "Maturation and Lagering" is all of 3.5 pages. A few selected quotes below:

_______________________

Maturation is the time between active fermentation and filtration, or, in the case of unfiltered beers, consuption, during which the beer looses its "green beer" character and reaches its best flavor. Maturation is due mainly to two factors: first, the slow working of the yeast, reabsorbing and metablolizing by-products such as acetaldehyde and diacetyl that were excreted earlier; and second, the floculation and dorpout of suspeneded yeast cells, so tha the beer loses its yeasty taint and the flavor of malt and hops comes through.
...
The traditional method of maturing a lager beer is to lower the temperature slowly over a period of about a week, from primary fermentation temperature to around 32 F. This procedure gives the lager yeast time to adapt gradually to the lower temperatures and slowly continue to work.
...
The lager periods recommended here depend on using the modern fermentation methods described int he previous chapter, specifically, a primary fermentation temperature of 50 to 55 F, and, if required, a diacetyl rest at the end of primary fermentation. If you follow the old lager brewing practices of fermenting very cold (42 to 46 F), with no diacetyl rest, then you may have to lager the beer for months to bring down the "green beer" flavour notes.
...
Some American lager breweries do not find it necessary to go through a cold lagering. They alllow the secondary fermentation to go on at primary fermentation temperature, and crash coll the beer only 24 to 48 hours before filtration. This procedure saves energy costs and can produce excellent, fully mature beers in less time than the traditional method, but requires a cooperative strain of yeast in order to get good dropout and avoid autolysis. If, like most homebrewers, you work mainly with the European lager yeast strains, you will get better (if slower) results using the modern German method of lagering.

_______________________

So, sounds like you don't have to do it, IF you've got the right yeast... Basically, there are good reasons for tradition -- that's what worked to get rid of the "green beer" taste -- but there is also more than one way to skin a cat.

Cheers, Brian

 

[Stuster]

Well, very interesting stuff. If the modern American mega-breweries do it, I am sold. I know their product is not the most wonderful drink (I'm not going to use the word beer), but they do produce a substance that is almost entirely devoid of flavour. If there were any off notes there, they would stand out a mile.

Also, the reasons given for lagering given do not convince me entirely.

Autolysis does not seem to happen very much at the homebrew level.
The yeast etc will drop out given time.
It was my understanding that the diacetyl rest was to clean up diacetyl, rather than the lagering process itself. Also, since the yeast work at their optimal level at around 10C, why would they work better at clean up after themselves at 2C? Not saying it's not possible, it's just that I've never seen an explanation for this, other than 'it's tradition'.

Anyway, thanks for posting that, Brian.

 

[Dr Gonzo]

As far as traditional lager brewing goes, Noonan's 'New Brewing Lager Beer' has it all, if you want to know how and why. A bit technical, but very explanatory.

 

[Stuster]

I understand the how, Dr G. Just wanted to have some info on the how online (to avoid buying the book I guess).

Edit: I was also interested in this as I know that there are brewers who have won prizes for lagers (me included) that were not lagered (wonder what to call them exactly). It appears that the judges were not able to notice any glaring faults in these beers, and I guess I was hoping somebody had either some knowledge on this they could share, or even better somebody had done a side-by-side test to see what difference it made.

Ah, for anybody who is interested I found this in a post by John Palmer on the Brewboard.

Guys, I feel your pain, I have asked the same questions to the yeast experts at Lallemand, Wyeast, and Whitelabs.

How does lagering differ from cold conditioning?
a. Not very much.
b. They're the same thing.
c. Lagering is for lager yeast and cold cond. is for ale yeast
d. Lagering involves yeast action on fermentation byproducts, while cold conditioning merely encourages haze/tannin precipitation.
e. All the above.

Answer: E - All the above. All yeast produce fermentation byproducts. All yeast require a conditioning period at the tail end of fermentation to reduce those byproducts. Ale yeast do it quickly and nearly simultaenously while lager yeast take longer. Lager yeast strains produce more sulfur gas compounds than ale yeast, and the colder fermentation temperatures retard diacetyl takeup by the yeast. A diacetyl rest at warm temperatures will take care of the diacetyl in a lager beer, but the sulfur compounds remain and need more time to offgas.
A big part of lagering is clarification. One expert at Lallemand told me that clarification was the Biggest part of lagering. This is why the conditioning aspect actually goes faster at warmer temps ex. 45-50F vs 35-45F.
If you do a diacetyl rest at 65F after lager primary fermentation, then conditioning/yeast cleanup is mostly done. Near freezing lagering should give you a clearer, smoother beer than lagering at warm temps, all else being equal.
Two summarize, Lagering does two things:
1. Yeast conditioning, which works better at warmer temps
2. Clarification, which works better at colder temps.

Cold Conditioning is the same thing for ale yeasts, except that the yeast aspect happens so quickly, that the clarification step is all that's really left to do.
Good Brewing,
John

From this, I struggle to find any reason to lager.

 

[jayse]

Even the noonan book doesn't go into that greater detail on whats actually happening other than whats already been mentioned in this thread. He sums up pretty much all those basics which have been posted here in a few paragraphs plus a bit more and then goes into a few pages on the 'how' you should do it etc, but as far as the 'why' and whats happening he doesn't really give a hell of a lot of the extra information your looking for.

I do remember a brewing network show with some guy from the gordon burch brewery or whatever its called discusing a few more aspects, I don't really remember it much but have vague memories of him talking about a lot of the other benefits of lagering from such things as improved foam formation and retention and a few other aspects outside of the more commonly known ones.

Maybe check it out if your interested and can track the show in question down.

 

[DJR]

Stuster, that beer you brought to the last brew day - the Community Ale with 1007 - i was thinking about the taste of that afterwards and remembered that you don't CC your beers at all. It was bright, clean and with no obvious off-flavours. Doesn't really match up with what you read about that yeast - that it needs CC'ing to get clear/condition the flavour.

I guess lager process is somewhat the same - if you have a dusty/nonflocculent yeast it will help it clear, but maybe that's a commercial requirement since trying to filter 40,000 hL of cloudy beer through kieselguhr might cause some major wastage?

I hear that Barry doesn't lager his lagers, and he wins so many competition medals he probably has about 10 fireplaces installed, so he can have enough mantelpieces!

 

[Guest Lurker]

Kunze devotes all of half a page to lagering, makes no mention of yeast metabolic processes, suggests that the point of lagering at 0 to 1 degrees is to encourage precipitation of yeast and cold break particles.

 

[deadly]

So are we suggesting the no lager method for lagers?

 

[discoloop]

So stuster, do you just ferment, bottle (or keg), carbonate and drink?

My first lager is currently in the bottle carbonating now. When they're all carbed up I was going to chuck a few bottles in the fridge for a month or so, then compare to the ones that were left at room tem. Sounds like a worthwhile experiment, now!

 

[Ross]

I've posted this a few times in the past, that i've found no benefit in the traditional method of lagering. However long I've left the beer in a secondary cube (up to 4 months), once I've kegged & carbonated it, it's still taken another few weeks to come good. I now crash chill for 24 hours after doing the diaceytl rest, filter direct from the fermenter into the keg & carbonate. The beer can be good from day 1 but generally needs 2 to 4 weeks before reaching it's peak. I just did a Schwarzbier this way - 2 weeks in the fermenter, & kegged for 3 weeks before entering our clubs dark beer competetion - It got 1st place with a perfect score - not bad for a lager that for most wouldn't have even reached the kegging stage.

Cheers Ross

 

[deadly]

Would carbonating then lagering be better than lagering in 2ndry then?

 

[razz]

That's what I generally do deadly. I chill the beer in the fermenter to get the yeast to drop out and then keg, carb and leave in the keg freezer to condition/lager.

 

[DJR]

Hmm so now we have, courtesy of AHB

No chill method
No sparge method (BIAB)
No lager method

That's a pretty good list of brewing techniques busted and broken...

My lagers do taste better after a month or so in the fridge, but i put them in the fridge pretty much the day they reach terminal gravity after the diacetyl rest. Perhaps i might be better off leaving for a week, then CCing to drop the yeast, then bottle.

 

[Stuster]

I don't have any method of lagering, but I can keep the ferment at the right temps for lagers during the winter. I made a couple last year which were ok to my tastes and was considering whether to bother doing some lagers again this winter. On doing some reading I was struck by the complete lack of detail when having a look for some info on lagering. It's very interesting that supposedly pedantic books like Noonan have little/no info on it either.

Ross' experience is really great to hear. All this suggests to me that lagers do need a fair amount of post-fermentation conditioning (makes sense that you'd need this to get a smooth tasting beer), but nothing I've seen so far has actually given a reason (other than yeast settling) why this shouldn't happen at warmer conditions than lagering temps. Lager yeast will be more active and less stressed at 10C than at 2C.

It certainly seems worthy of an experiment anyway. discoloop, sounds like one good way to test it. I'll have to try the same thing. One thing that may bias this experiment is carbonation level. You'd need to put the non-lagered bottle into the fridge a couple of days before the experiment so there is no difference between the carbonation levels of the two beers (they might be different if the bottle's only been in the fridge for a few hours say). Anybody willing to do a split batch experiment to test it out?

Pat, eat your heart out.



D'oh, think I'm still a thousand words short. :lol:

 

[deadly]

I've got 1 cube lager from 12/06 at 1 lagering
1 cube lager from 02/07 at 12 cold condition cellering
and 1 cube lager at room temp in 2ndry all were fermented at 12
In the fermenter from yesterday is Ashers GT Rice lager maybe I could split that?

 

[Stuster]

Well, if you did, you could have a method named after you. :lol:

 

[devo]

i find that my lagers responded much better through extended kegging and conditioning(min 4 weeks) rather than secondary fermenting. Eitherway I still let it sit in the secondary for b/w 8- 10 days before kegging.

 

[tangent]

I've found 2 weeks in the keg (little or no pressure) beats 2 weeks in a cube. i don't know why, but stainless steel and cold is beer goggles for beer. rack or filter out of the stainless after 2-4 weeks and the difference is astounding compared with a cube in the fridge. maybe it's just the curved arse concentrating the yeast?

 

[oldbugman]

Stu,

Who needs an earth!

Wire it up big fella!