Lager Step Starter ?'s

[Arg1129]

I am planning on doing my first lager within the next couple weeks and have a question about the starter. I am going to brew the Traditional Bock from Brewing Classic Styles

SG 1.069
Mash at 154
Ferment at 50

My question is about the stepped starter.

MrMalty says that i need to do a 2L/2L step starter using two vials of WLP833 but YeastCalc.com says to use one vial of WLP833 with the same 2L/2L stepped starter.

My starters consist of a StirStarter stir plate with a 2L flask. I also use the sponge stopper with the stir plate. I plan on cooling and decanting the first starter and then adding the 2L of cooled wart for the second step.

Can anyone tell me what i should do for the starter. Also do i need one or two vials of yeast.

Thank you in advance...

 

[RoundKid]

Go with yeast calc's numbers or look at brewersfriend.com. Both use Kaiser's numbers rather than Chris White/Jamal. Jamal's numbers are not accurate when using a stir plate.

One vial with two 2L steps of 1.04 wort is fine.

 

[Arg1129]

Thank you ill use yeast calc then.

 

[isleofman]

Go with yeast calc's numbers or look at brewersfriend.com. Both use Kaiser's numbers rather than Chris White/Jamal. Jamal's numbers are not accurate when using a stir plate.

One vial with two 2L steps of 1.04 wort is fine.

What source do you have for their numbers not being accurate? Especially, Chris White?

 

[RoundKid]

What source do you have for their numbers not being accurate? Especially, Chris White?

My Source: http://braukaiser.com/blog/blog/2012/11/03/estimating-yeast-growth/

White/Jamal's data in "Yeast" (same as Mr. Malty) is for not agitated starters. This is why yeastcalc.com and brewersfriend.com give different results for a stir plate than mrmalty.com.

On yeastcalc and BF there are two options for stirred starters, one using White's data and one using Kaiser's. the difference between that data is why the OP was getting different results.

I have not done any experiments and do not have a microscope, but Kaiser's data feels true based on my limited experience growing yeast.