Harvesting Yeast from Starters: UPDATE!!!

[Brulosopher]

I'm going to try this.

You'll never go back!


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[user 141939]

I don't see why you can't know how much yeast you are harvesting. You've already calculated it. If mr. Malty or whatever tells you that your are making (for example) 250 billion yeast in a 2.5 liter starter. Then taking .5 of that gives you 250/5= 50 billion cells. Assuming the starter was well mixed before pouring off.


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[user 141939]

Simple math.

Plug your numbers in a calculator. I like this one. Then, say you make a 2 L starter, but save 0.5 L, then divide the cell count (after starter) by 4.

When making a starter out of your harvested yeast, assume the same viability as a liquid yeast starter.

For my one year old yeast, I entered 1 billion cells manually in the Starting Yeast Count box. Then I figured the number of step ups I needed.

Cheers!

Woops. I just posted this same math because the original article just assumes 100 billion for some reason. How do you calculate viability? So if I harvest 60 billion from a starter and it sits in my fridge for 6 months, how do I figure my new count? i tried searching the interweb thingy for an equation but couldn't find one.


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[FuriousE]

Just pitched my first harvested yeast into a Fixed Gear clone I made. Its happily bubbling away. I really like this method so far!

 

[logdrum]

Woops. I just posted this same math because the original article just assumes 100 billion for some reason. How do you calculate viability? So if I harvest 60 billion from a starter and it sits in my fridge for 6 months, how do I figure my new count? i tried searching the interweb thingy for an equation but couldn't find one.


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I like this one:

http://www.yeastcalculator.com/

BTW, 60b @ 6 months gets you 13.2b initial cell count