Lager yeast starter step-up

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MTHarrington

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Making my first Lager... (1.048 OG)

I have a 2 liter Erlenmeyer flask. I am going to pitch this cold so I know I'll know I need high yeast numbers.

I have one yeast tube from Wyeast, stir plate and yeast nutrients.

I need around 350 billion yeast cells.

I have been looking at Mr. Malty's yeast calculator... and basically for a 5.25 gallon batch with an OG of 1.048 it says I need 2.76L of starter if I only want to use one yeast vial at 97% viability with a stirplate.

Obviously, I need to step propagate since I only have a 2L flask.

SO

I read here:
http://billybrew.com/stepping-up-a-yeast-starter
with a chart that basically says if I want to step with a 2 liters, the best I can do is 300 billion for 2 steps.

Then I go to Wyeast's calculator and it says something completely different...

http://www.wyeastlab.com/hb_pitchrate.cfm

It says I don't even need to step up... that I can take .475L, make a starter and pitch and I'll have 16.1 million cells/ml

and according to their pitch rates in million cells/ ml
http://www.wyeastlab.com/hb_pitchrates.cfm
I need 12 million cells/ml so that is plenty.

OK. so that's quite a difference, unless I'm using Wyeasts calculator wrong.

and now for even more fun stuff...

on Northern Brewers info page here:
http://www.northernbrewer.com/documentation/YeastPitchingRates.pdf

it says that if I my first step volume is 1 liter and my second step is .25 liters I should propagate 397 billion cells (with a stir plate)
And that is plenty for what I need.

I am confused. Who is right? I really don't need this to be overly complicated, but I do want to make the cleanest lager I can... without going totally overboard.

Is this a RDWHB moment?

I'm leaning towards doing a 2 step propagation of 1.5 liters each and living with results. Mr. Malty's calc seems to say I can't make nearly as much yeast as I can on Wyeast's site or Norther Brewer.

Thoughts? I've poured over the internet looking for a good answer to this discrepancy.. and most people default to Jamil's site, but I can't understand why the manufacture and a distributor of yeast would say otherwise (they have more skin in the game - of course they would want to sell you more yeast/equipment/make good beer and buy more stuff from them)
 
That's .475 gallons from the Wyeast calculator, not liters.

The wyeast numbers are low for my tastes. I like to pitch lagers at a pretty standard 1.25m cells / plato / mL, so for your beer about 15m/mL.

On Mr. Malty, I get asked for a 2.5L starter with your numbers. That brings the malty and the wyeast calculators to be relatively close to each other.
 
Edit.

I see your numbers now..

So if I need a 2.5 liter starter - and I have one 100 billion cell capsule and a 2 liter flask - what would be the best way to step this?
 
The Mr. Malty calculator is kind of a PITA to use for stepped starters. Why do you prefer Mr. Malty's numbers to Wyeast's? Both of them are very crude estimates banking on some fundamental assumptions. Without testing your slurry, they really just get you into the right ball park. If you want a large pitch, you could do a 1L and then a 1.5L step sequence. Otherwise, I think you'd be in good territory doing a single 2L starter.

By the way, those numbers in the cells on billybrew don't indicate steps, they indicate the number of 100B cell vials used to innoculate the worth. They also presume no shaking. Use a stirplate if you can, and shake the sucker as often as possible if you can't.
 
I agree, for a 1.048 lager I think a 1.8L starter (about as much as you can fit in a 2L flask without it going volcano on you...and even then it occasionally will) on a stirplate and made with a fresh pack/vial will be OK. Just make sure to aerate both the starter and the batch really, really well and when they are cold. Well, the starter may not be 'cold' but I'd chill it below room temp, areate and pitch, then let it naturally warm to room temp.

FWIW, when using the Mr Malty calulator you can 'fudge' the viability number to make stepped starters because the calculator conveniently assumes a full smackpack/vial is 100 billion cells. 50% viability is 50 million cells...250% viability ('fudged' number) is 250 billion cells. So just calculate your first starter exactly like you normally would, then take the result from that and adjust the viability number to set your starting population for the second step. Duck soup.
 

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