Another Mr. Malty Calc Question...

[Speyedr]

Wondering if I am overdoing this or if I am missing anything...

I'm going to brew 10gal of Premium American Lager two weeks from last Saturday. According to the calculator I need 4 packs/vials in 2.84L to get the necessary 741 billion cells for my 1.053 wort. However, I don't want to buy $25 worth of yeast. I also have 1x500ml, 1x2000ml and 1x3000ml flasks and 1 stir plate.

4 packs is approx. 400 billion cells. If I change my volume to 5.5gal the calc says I need 407 billion cells. That's good enough for me, but I need 2 packs in a 1.78L starter, and I only have one pack. For one pack I would need over a 4L starter, so I will need to generate 200 billion cells from my one pack so...

2 packs is 200 billion cells. If I change my volume to 2.7gal then the calc says I need to pitch 1 pack in 1L of wort. This I can do. So the plan is...

On Saturday I will pitch 1 pack into 1L of wort. After 18-24hrs I will then pitch this into 1.78L of starter (Sunday). Then after another 18 - 24hrs (Monday) I will chill the starter down for 48hrs.
On Wed. I will decant the supernate and pitch this slurry into 2.84L of starter. After 18-24hrs (Thurs) I will chill it down in the fridge for another 48hrs. Then on Brew Day I will decant and pitch the slurry into 10gal of my finest wort.

Does this sound good? Am I missing an easier way to figure this out in the calc or to generate the necessary yeast without buying additional packs, vials or sitrplates?

[jamilz]

Sounds good. 1 package into 1 liter results in about 2 packages. 2 packages into 3 liters results in about 4 packages.

One of the things you can do in the calculator is to move the growth slider. This tells you the amount of starter needed if you want to use less packages and a bigger starter volume.

For example, it will probably tell you that you can use 2 packages of yeast in a 7 or 8 liter starter instead of 4 packages in a 3 liter. (just guessing)

[Speyedr]

Cool, thanks. I used the slider but had to stay under my 3L limit. You'll know if it works when I take the gold at the NHC for it...

EDIT - actually, the calc says 2 packages (200 billion cells) in under 2L will yield 4 packs, or 400 billion cells. Then I throw that 4 packs worth into 2.8L and that should yield over 700 billion. Am I doing this right??

[jamilz]

Sounds correct.

[Speyedr]

Thanks... Next time I'll just e-mail you direct... again!