First Try at Yeast Stepping. Numbers make sense?

[jbsengineer]

I plan to try stepping up my yeast starters in order to ferment a 12.0G batch of 1.069 ale.

With 1x100B vile I planned a 2.0L starter on a stir plate, followed by cooling, decanting, and pitching the yeast into another 2.0L starter on a stir plate.

By calculations on www.yeastcalc.com this would yield me ~582billion cells.

Anything wrong with this thinking?

 

[beerkrump]

You are using a 1.040 SG starter, right? If so, I'd say you are good to go.

 

[jbsengineer]

Close, 1.037.

 

[jww9618]

What is the production date on your yeast? Your numbers are right, but that's assuming your yeast was manufactured today and has 100B healthy cells. Your yeast is probably a month old which would require a 2L starter then a 2.5L starter for 597B cells.

 

[jbsengineer]

What is the production date on your yeast? Your numbers are right, but that's assuming your yeast was manufactured today and has 100B healthy cells. Your yeast is probably a month old which would require a 2L starter then a 2.5L starter for 597B cells.

Great point. I was calculating yeast manufactored today.

I'm grabbing the yeast on my way home tonight. So assuming it's 1 month old and I do not have a larger than 2.0L liter I'm a little lost on what I should do.

Do a third step with a 1.0L starter? That would bring me up around 572B. So it would be 2.0, 2.0, 1.0.

 

[jww9618]

See if your LHBS sells a 1 gal jug. I bought a couple just for starters.

If they don't, I would just make a 2L and 2L and be done. Under pitching by 34B cells won't have any negative consequences on the beer.

 

[ThreeDogsNE]

It's a starter that you want well oxygenated, so the usual reservations about oxygen permeability of plastic jugs does not apply. If you can't readily nab a glass jug, grab a plastic one. In a pinch I used one of the plastic jugs that I get RO water in. There is a ridge diagonally across the bottom, so I had to use a 1" stir bar set to the side of that ridge. Not elegant, but effective and cheap -- the jugs are net 30 cents.

 

[jbsengineer]

See if your LHBS sells a 1 gal jug. I bought a couple just for starters.

If they don't, I would just make a 2L and 2L and be done. Under pitching by 34B cells won't have any negative consequences on the beer.

First 2L starter went great. Then I used a 1Gal jug for a second starter and it was a disaster. Yeast cake on the counter, stir plate, yeast "canals" all down the side of the jug. Obviously needed a larger jug or multiple smaller starters to compensate for the heightened fermentation.

I stopped the stir plate a bit early as to slow down the process. So now I have NO IDEA how many cells I could possible have at this point. I know a lot made there way to my counter...

I was thinking I could make a 1L starter and let them pollute themselves, would that give me a baseline?