Large Starter Question

[mccumath]

Hey Guys,

Have a few questions, and don't have much time to type before going to work... I am sure it has been answered, but if you could help point me in the right direction, it would be much appreciated.

1: I plan on making a beer that is 1.090 gravity, and have used Mr. Malty to determine that I need a 4.4 L starter for this beer using 1 package of Wyeast Pacman. How does one go about stepping up a starter for this beer? My knowledge of starters is that I have made a total of 1 starter currently for a medium gravity beer.

2: When adding a little over 1 gallon of starter to my fermentation vessel, I take it that I would decant most of this and pitch the slurry? That is how I did my last starter, but just checking.

3: I am not sure what type of vessel to do a 1 gallon starter in... I currently have a 1000 ml Erlenmeyer flask, a 1/2 gallon growler, and a 5 gallon glass carboy... Any suggestions before I have to run out and buy something else?

As always, thanks for the feedback! Off to work I go...

Ryan M.

 

[Suthrncomfrt1884]

When I step up starters, I usually start with 1000ml. I'll let the yeast settle, cool, and decant the liquid. I then make 2000ml of wort and add the yeast slurry to it. Again, let it ferment, settle, cool, and decant again. At this point, I would step it up to 4000ml in the same manner. I just double my wort size each time.

Decant and pitch to your fermentor.

As for your vessel...4000ml is over a gallon, but I think you'll be fine if you short yourself a tiny bit and just use a 1 gallon growler. Just make sure you put a blowoff tube on it...just in case.

 

[SterlingHopper]

When I step up starters, I usually start with 1000ml. I'll let the yeast settle, cool, and decant the liquid. I then make 2000ml of wort and add the yeast slurry to it. Again, let it ferment, settle, cool, and decant again. At this point, I would step it up to 4000ml in the same manner. I just double my wort size each time.

When you step up a starter like this, you are actually creating a lot more yeast than when you only make one giant starter (they go through 3 growth phases instead of 1).

Check out this calculator for calculating how much yeast you can expect from stepping up your starters. It will help the OP solve his initial problem of vessel size, provided that you're willing to make more than one starter.

 

[mccumath]

Okay, so to make sure that I understand correctly... And one other thing I failed to mention in my original post, I do have a stir plate, so continues oxygenation is available.

SterlingHopper: I am perfectly willing to make several starters as necessary. It appears as though you can use a normal growler for this type of starter set up because you alleviate growing a large starter with one large vessel. So, according to the yeast calculator that you sent me, I could start with a 1L starter inoculated with 125 billion cells (1 Wyeast package), let it ferment to completion, cool, decant, and add to another new 1L yeast starter. At 5.5 gallons of 1.090 gravity wort, and a viability of 61% (12/11/11 package date), I could accomplish the appropriate pitching rate of 332 billion cells (4 billion cells short of what it calls for)? Or I could make a slightly larger 2nd starter and accomplish a slight over-pitching rate?

Please let me know if my calculations are correct, as this would save me a ton of headache and make stepping up starters much easier that I had initially thought.

Thanks for you guys' help, it is much appreciated!

Ryan M.

 

[acefaser]

Watch this

 

[SterlingHopper]

Please let me know if my calculations are correct,

I would only assume the Wyeast Activator pack only starts with 100 Billion cells, but yeah those numbers look right to me.

If you've got a stirbar that spins in your growler, go for it.

 

[mccumath]

Gotcha. Yeah, my bad. They are only 100 billion cells... I had a lapse... haha.

Anyways, looks great, am excited to give it a whirl.

Thanks,

Ryan M.