Mr. Malty question...lagers

I am going to be getting a starter going today for an Oktoberfest that I will be brewing shortly. According to Mr. Malty it says that I should be using 2 vials of yeast and then make a 3.73 quart starter.

I have Malty set for the fewest yeast packs(vials) as possible and it still reads 2 vials. I am not going to buy 2 vials so my question is this.... Instead of making a 3.73 qt. starter should I just bump that up to about a 6 qt. starter?

did you set your preference to lager fermentation?

philrose said:

did you set your preference to lager fermentation?

Click to expand...

Yep, everything is set. Lager, age of yeast, volume, gravity, stirplate etc.

then I'd go with it, stepping up the starter one extra time as you had mentioned (had to re read op, whoops)

You could do a two step starter. 1 vial into 1 Liter, let it finish and chill for 2 days and decant. Add another ~2.87 liters, let it finish, chill it, decant and pitch. That'll get you 523 billion cells which I think is close to what you need without knowing what numbers you are using.

I think it has to do with tempering yeast health with cell mass. The calculator doesn't 'allow' you to use too few vials and too big of a starter because it's too much to expect of an intial yeast count to multiply up to such a large final cell count and still be healthy. If, for example, you start with a ~70% viable yeast vial (so ~70 billion cells) and you need 475 billion cells for your lager then you are expecting the yeast to increase it's cell mass by over 6.5x in one starter. The yeast just won't be healthy after all that work. EDIT: And they will often run out of nutrients before they even reach such lofty goals anyway.

The Fourteen Essential Questions about Yeast Starters article explains why it's not good to make starters that are too small (keep this in mind whenever you plan to step up because that second step may be too small, also detrimental to yeast health) but doesn't really say why too big is bad. So I'm speculating but that's my guess.