Optimum temp to propagate a lager starter?

[jat147]

Howdy,

I'm about to make a big yeast starter from a vial of WLP838 lager yeast, and can't decide the best temp to run my stir plate at?
I'm thinking that it should be cooler than the 72 to 75F that I propagate ale yeast at, but not as cold as the ferment temp. As I said it's for a big starter, so I'm seeking the best cell count possible when I'm ready to pitch and want an optimum temp to run the prop cabinet at.
Anyone got any ideas?
Thanks

 

[motobrewer]

low 70's.

 

[wilconrad]

When are you going to brew? If it's going to be several days (4+), I'd go with a temp closer to primary (55-60) as this will provide the 2 minor benefits of getting your yeast dialed-in to fermenting around this lower temp and will not produce any off flavors (but these would be in such low quantity in your starter, this is nearly a non-issue).

If you're brewing soon (in the next 1-3 days), I'd do the starter at ale temps to make sure you get your cell count up to where it needs to be. The downside of using this higher temp is relatively minor, and you'll avoid underpitching.

 

[jat147]

It's not going to be used for 5-6 days. I'm stepping it up 3 times to get to the cell count needed for the lager I'm brewing, this is just the first stage.

Seems like a difficult balance to judge?
Do I get the yeast used to working at ferment temp - or go for out and out biomass increase?

 

[beernutz]

Mr. Malty, as usual, has something pertinent to say on the issue:

Q: Does a starter need to be kept at the same temperature as it is going to ferment the batch of beer later?
http://www.mrmalty.com/starter_faq.php

 

[motobrewer]

as long as you don't shock them down to ferment temp (ie, pitch 70F yeast into 47F wort) it should be fine.

I propagated wy2206 at 70F, cooled it down and pitched into a 1.072 bock. It fermented out to 1.018 within 12 days.

 

[wilconrad]

It's not going to be used for 5-6 days. I'm stepping it up 3 times to get to the cell count needed for the lager I'm brewing, this is just the first stage.

Seems like a difficult balance to judge?
Do I get the yeast used to working at ferment temp - or go for out and out biomass increase?

If you're going to be doing 3 steps and brewing in 5-6 days, I'd use ale temps (70ish). I wouldn't risk underpitching. My $0.02.

 

[motobrewer]

3 steps is a lot. i'd personally just buy another pack or two to use in the starter. especially if you plan on reusing this yeast.

an extra $7 now spread out over the next few beers is worth it.

 

[jbaysurfer]

If you're stepping up and decanting at each step there's really no downside to doing it at ale temps. If you're pitching a gallon of starter wort into a 5 gallon batch then fermenting it warm will create some flavors you wouldn't want in your final product.