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Starter yeast question

Yeast & Fermentation
#1

Hello everyone. Starter yeast question here. I am trying to make my first lager, an Oktoberfest. I have been talked into making a 2 stage starter. Here is where I am at. Tell me if I screwed this up royal. Made first batch with 2 litres water and 200 grams DME. Cooled to below 90 and pitched my yeast. Sat for a few days at room temperature them moved to a fridge at 55 for 3 days. Made my first attempt at “pouring off” to get to just the yeast. Made second batch with 1 gallon water and 400 grams of DME but no yeast and poured in what was left of the yeast from the first batch, which was very little.

So have I screwed this up royally?

#2

You did it right. I assume you cooled the gallon of starer wort down before you put the yeast in, though. I wouldn’t run a starter as warm as you did; 65-75 is a good range, but I don’t think you’d kill the yeast at that temp. You probably just won’t develop yeast that’s as healthy as you would at a cooler temp.

#3

That’s good to know. Someone told me to pitch it below 90 so that’s what I did both times.

#4

Once you hit 80 or above, your yeast health starts to really suffer. The cell wall permeability gets bad, fatty acid production in the cells is off, and cell mutation goes up. Cells grow faster at warmer temps, but they’re not very healthy. General wisdom is that your starter should never go over 80.

#5

So I am screwed at this point. Was the procedure correct otherwise?

#6

Other than the too warm pitching, the proceedure was exactly correct, assuming you aerated the wort properly. I give it a good shaking after I’ve cooled it down, and then don’t use an airlock to seal it. Instead use a piece of aluminum foil over the top so air can still get in. And every now and then, give it a swirl. That keeps the yeast suspended and promotes faster growth.

#7

No advantage to pouring off too much of the spent wort at then end of stage 1, If it is questionable, keep it and add to it.

#8

You’ll be fine. The thing I question is what is the original yeast volume. If you are pitching from a smack pack then a 100-200 ml should be your first step. If you are pitching a WL vial then your first step should be ~500 ml.

#9

Well, it removes as much of the ethanol as possible.

#10

Well, it removes as much of the ethanol as possible.[/quote]
I was just thinking better to pour less if there is a risk of pouring most of the good yeast down the drain.

#11

I was wondering if you would be better served making a 1 litre starter first then followed by a 2 litre starter after that for making a lager requiring lets say 350 billion cells. I was looking over the mr malty calculator and that what it seems to come up with. I am asuming a 5 gallon batch at so I may be of base here.

#12

What’s the logic behind that? Assuming they’re fresh, the (Activator) pack and WL vial should have roughly the same cell count. Regardless, those volumes are much smaller than the conventional wisdom suggests.

#13

Well it seems conventional wisdom has changed. The conventional wisdom used to be (before you could get pitchable amounts of liquid yeast and everybody had stir plates) was to pitch into small amounts of wort to quickly overwhelm contaminants and to mimic the the process that yeast companies use to grow yeast. That is to slowly add small amounts of oxygenated growth medium so as to keep the yeast in aerobic respiration and limit sugars so to not put them into crabtree effect.

White Labs suggests using 1-2 pints and 2 liter starter on the same page.

http://www.whitelabs.com/beer/homebrew_information.html

so I guess guess it doesn’t make it doesn’t make much difference.
relax don’t worry

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