# Lager Yeast



## Mclovin (17/7/11)

Hi all,

Just slaped together a pilsener with W34/70 dry lager yeast, first time i have used this particular yeast strain and was wondering if anyone may have any advice. I am maintaining 15'C in the fermentor on day 2. I did'nt bother with a yeast starter for this one just pitched 1 pack dry. Air lock is going bonkers ATM.


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## C-MOR (17/7/11)

Im using this for the first time too. I pitched at 9 degrees, certainly didn't go bonkers. is now slowly chugging along at 11 degrees atfer 7 days, i guessing another 7 to go. making lagers is hard without patience.


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## mxd (17/7/11)

I've used it and from my experience,

OP at 15 Deg I think you'll get a good whack of Diacytyl.

C-Mor at 9 degrees, depending on you OG and if you rehydrated, you may have a sluggish yeast that will probably produce too much Diacytel that it won't be able to clean up


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## seemax (17/7/11)

+1

15C too high.

Despite the varying opinions, pitching the dry yeast directly into the wort can mean the death of a many yeasties.

It likes to be rehydrated warm and in water (not sugary wort), then once it's happy in suspension you can get it down to ferment temp (10C) and pitch it.

Good luck... personally I use US05 at 15-16C and do faux lagers... it's fast, clean and 1 packet does the job.


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## Mclovin (17/7/11)

I have my fermentor in the garage on the concrete maintaining 12-15'C over the past 3 days. I may have to pray for some extra cold weather next week.


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## stakka82 (21/7/11)

I've used 34/70 a few times now. The first time I didnt do a diacetyl rest, and the result was undrinkable. 

Now I use the following method and I'm pretty happy with the results. I cant taste any 'butterscotch' or slick mouthfeel but I might have a high threshold personally for diacetyl. That said the few lagers I've done have gone down well with mates and the old man which is usually a good yard stick.

1. Pitch at 20-22 degrees, 1 packet 34/70
2. Chuck it in the hallway, which conveniently stays at between 9 and 15 degrees in winter, most often 11-13 degrees
3. After a week the grav is usually slowing to a point or so a day and I bring the fermenter into the loungeroom which usually stays at between 14 and 20 degres. I leave it there for a week or so.
4. Then I rack to secondary to bulk prime, bottle, and leave the bottles at ambient ie. maybe 18 degrees.
5. After 2 weeks of carbing i chuck the whole batch in their spare fridge for at least a month, which sits at about 4-6 degrees. 

Result is pretty clean, which im happy with without proper lagering in a secondary. I find that before chucking the bottles in the fridge for a month there's can be a slightly sulphurous smell to the beer, but this seems to disappear completely after the month or more in the fridge.


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## Wolfy (21/7/11)

An alternate way to achieve clean results from a lager yeast is to pitch cold (say 5-8C) and then gradually it it warm up to fermenting temp over the next few days. Since many/most of the yeasty-off-flavours are produced at the start of fermentation the cooler initial temp may mean that a D-rest is not always needed.
In addition (in theory) it is better to lager the entire volume of beer rather than bottle first and then lager later, however that is not always possible depending on setup and equipment.


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## Nick JD (22/7/11)

Sources say that 34/70 Weihenstephan is Wyeast's 2124. 

Wyeast says:

_This Carlsberg type yeast is the most widely used lager strain in the world. This strain produces a distinct malty profile with some ester character and a crisp finish. A versatile strain, that is great to use with lagers or Pilsners for fermentations in the 45-55F (8-12C) range. It may also be used for Common beer production with fermentations at 65-68F (18-20C). A thorough diacetyl rest is recommended after fermentation is complete. 

Flocculation: Medium-low
Attenuation: 73-77%
Temperature Range: 45-68F, 8-22C
Alcohol Tolerance: 9% ABV
_

I've found it's really sulphury above 12C, but not very diacetyly. Underpitched, it takes longer for the sulphur to fade (or makes more sulphur).


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## kevin_smevin (22/7/11)

Mclovin said:


> Hi all,
> 
> Just slaped together a pilsener with W34/70 dry lager yeast, first time i have used this particular yeast strain and was wondering if anyone may have any advice. I am maintaining 15'C in the fermentor on day 2. I didn't bother with a yeast starter for this one just pitched 1 pack dry. Air lock is going bonkers ATM.



You'd probably find that pitching 1 or 2 packets more would give better results - depending on your OG and volume of course. This yeast has 6 billion viable yeast cells per gram at the time of packaging. 11.5g pack = 69 billion yeast cells.
Recommended pitching rate for a lager is 1.5million cells/ml/degree plato.
So for a 23L batch of 1046 wort you need 1.5million x 23000ml x (46/4) = approx 400 billion cells - 5.8 sachets of yeast to pitch the correct amount of yeast. That seems like a hell of allot but it'd probably improve your results significantly.


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## therook (22/7/11)

Just my 2 cents worth is if you can't achieve a lower temperature try S189 next time.

Rook


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## Pennywise (22/7/11)

I used 34/70 a while ago, only pitched one pack & fermented @ 12. Diacetyl city, next time I use it I'll deffinatly be pitching 4 packs or making a big arse starter from 2124. 100% agree with therook, the last Lager I brewed was with s-189 (2 packs if I remember correctly) & fermented @ 19, as the way Craftbrewer do some/all of their Lagers with this yeast. Fermented for 10 days then crashed to 0c for another 10. Not as clean as clean can be but bloody good results for the process. YMMV


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## Rosscoe (22/7/11)

Mclovin said:


> I have my fermentor in the garage on the concrete maintaining 12-15'C over the past 3 days. I may have to pray for some extra cold weather next week.




I use this yeat a lot and with great results, however it does preffer to run at about 10deg. Above that you'll get some sulpher that will take a while in the bottle to settle down. Diacetyl will only be a problem for you if you rush the fermentation. You're obviously not going to "lager" it, so it'll need 3 weeks on the yeast, before you bottle, to eat up the D, which it definately will at 15deg. It should be fine, but give it plenty of time, both in the fermenter and in the bottle.

Next time you want to cook up a lager at those temps, try S189, which will produce very little sulpher, even at 15+ degrees. Will need the same patience during primary to eat up the D, but will be very drinkable. Either way, follow the advice already given by others and pitch two packets of yeast into a lager, which I think you should always rehydrate first. It'll really appreciate the start and that will get things going quicker and cut down on Diacetyl production in the initial stage.

Cheers,
Rosscoe


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## C-MOR (22/7/11)

mxd said:


> C-Mor at 9 degrees, depending on you OG and if you rehydrated, you may have a sluggish yeast that will probably produce too much Diacytel that it won't be able to clean up


Butter flavoured microwave popcorn all the way. It has also stalled @ 1020 after three weeks(OG 1054), pitched @ 9 and slowly rose to 12, still at 12.

WHAT CAN I DO?


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## Nick JD (23/7/11)

C-MOR said:


> Butter flavoured microwave popcorn all the way. It has also stalled @ 1020 after three weeks(OG 1054), pitched @ 9 and slowly rose to 12, still at 12.
> 
> WHAT CAN I DO?



A diacetyl rest. Bring it up to 18C for a few days - it'll also finish off the fermentation. And when you bottle/keg, save 300ml of swirled trub (swirl until it's muddy) in a PET bottle in your fridge. If you get about 50-75ml of trub settling in the bottle you've got a great pitch ready to go for your next batch. 

Let it warm up to room temp first, and taste the beer on top to make sure it's okay - then just swirl it up and pour it in. If you start a lager at 22C, and set your fridge to your ferment temp (single batch) by the time it's bred up to its correct population and starts eating maltose ... the temp is your ferment temp. Yet it bred up at 20C --> 12C.

A handy way to speed up a lager ferment is to step the temp. I do quick ferment lagers by pitching at 20C and setting the controller to 11C. The every day raising it by 1C once it's got foam on top. You can pump out a fault-free lager in a week this way - another 4 days to clear it after that. Many of the commercial breweries also raise their temp during ferment. S189, from 11C to 20C produces the same beer as leaving it at 11C for weeks - but not as fruity (IMO) as the 19C advocated by folks here. I find US05 is more neutral at 19C than S189.

You can also spend 5 months making _the world's most perfect lager_ - but that's for the patient.


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## Bribie G (23/7/11)

Last year I whacked through a quick Aussie Lager for a competition using S-189 and it, too was diacetyl infested. I just sat it in a keg at garage temperature for a month and it cleared up nicely. Didn't make the comp, though.


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## Nick JD (23/7/11)

Here's a test for whether your beer is dicetyly:

_So how do you know if your beer will need a diacetyl rest? There is a diacetyl test which any homebrewer can do. It requires two glasses , some foil or plastic wrap, some hot water at 140-160F (60-71C), and some cold water. The principle is simple. At warmer temperatures, the precursor to diacetyl, alpha-acetolactate (AAL), will oxidize quickly into diacetyl in your young beer. In essence, you will be testing for the presence of excessive levels of AAL in your beer. So, here is how the test goes:

* Put a sample of your young beer into each of two glasses and cover them.

* Put one glass in the hot water bath and keep it there for about 10-20 minutes.

* After 20 minutes, cool the hot beer to the same relative temperature as the control sample by placing it in a cold water bath for a few minutes.

* Remove the covers and smell each of your beer samples (don't forget which is which). One of the following things will happen:

1. Neither sample smells buttery. This is the best-case-scenario because it means that all of the diacetyl precursor AAL has already been converted to diacetyl and your beer does not need a diacetyl rest.

2. The heated sample smells buttery, but the control sample does not. This indicates that there is excessive AAL in your beer and you should ramp the temp up (if it's a lager) by 5-10 F (1 - 2C) for a diacetyl rest, and age it for a few days to allow the AAL to form diacetyl and the yeast to metabolize the diacetyl. For ales, a few more days of conditioning is indicated. You need to do the test again to insure conversion is complete and your beer is stable.

3. Both samples can smell like butter. This might indicate a pedio infection, in which case you should probably dump the beer. It could also mean that your yeast cannot metabolize the diacetyl because the majority of them are petite mutants.
_

I've never tried it, but it sounds interesting.


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## C-MOR (23/7/11)

thank you for the responses Nick.
Ive not had to deal with diacetyl before so i have a couple of questions.
How fast should should i raise from 12 to 18?
Yeast appear to be asleep, do they need to be roused or will the climate change alone get then up and going again?

Ive brought this on my self and the poor little yeasties. pitching cold but not doing yeast preparation. WWJS


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## Nick JD (23/7/11)

C-MOR said:


> How fast should should i raise from 12 to 18?
> 
> Yeast appear to be asleep, do they need to be roused or will the climate change alone get then up and going again?



This time of year, I just turn the temp control off and open the fridge door for my diacetyl rests if one's needed.

The raise in temp will rouse them.


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## C-MOR (23/7/11)

Nick JD said:


> This time of year, I just turn the temp control off and open the fridge door for my diacetyl rests if one's needed.
> 
> The raise in temp will rouse them.



Thanks


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## Nick JD (23/7/11)

C-MOR said:


> Thanks



No worries. I've found it's hard to wreck a lager after it's 3/4 of the way to FG. Play good-cop, bad-cop with it - get busy with the phonebook on it at the end.


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