German Lager Brewing Techniques -- Yeast Pitch Rate

Pitch rates generally are 'referenced' to the size of the batch and often times reference the gravity of the wort.

The pitch rate often quoted by folks is the George Fix pitch rate for the case of repitching previously used yeast which is:

· 0.75 million cells/ml/°P for ales

· 1.5 million cells/ml/°P for lagers

For the case of brewing a 12 °P lager this would yield 18 million cells/ml and once again this would be for the case of repitching yeast that was previously used to brew a batch of beer.

For a typical 20 liter batch of beer this pitch rate could easily be derived to a yeast amount: 18 million cells/ml x 20,000 ml = 360 billion yeast cells.

Cheers!

 

30 million cells/ml sounds really high.
Also, I think that 25% yeast solids number sounds pretty low, like a worst case scenario for unrinsed trub. I know Mr. Malty says this number comes from George Fix, but it doesn't seem realistic.

That aside, 1 Billion x 50% = 500 Million (not 50 million)

 

Since you're emphasizing that this is for the case of repitching yeast that was previously used to brew a batch of beer, what would you say is the proper pitch rate in cells/ml/°P for yeast that was not previously used to brew a batch of beer?

 

A pitch rate of 30 million cells/ml would ‘correlate’ to a wort gravity of 20 °P (SG = 1.083):

1.5 million cells/ml/°P x 20 °P = 30 million cells/ml.

So, if you are brewing a lager like a Doppelbock and repitching yeast that was used to previously brew a beer, then a rate of 30 million cells/ml would be proper.

Cheers!

 

I tend to agree.

 

As Jamil Zainasheff stated: “…the health and vitality of fresh laboratory cultured yeast are superior to yeast harvested from normal fermentation.”

Cheers!

 

So what's your recommended pitch rate (cells/ml/°P) for these spectacularly healthy and vital yeast?

 

http://www.mbaa.com/store/Pages/72642.aspx

I am off to celebrate the 4th of July.

Happy 4th of July everybody!

Cheers!

 

Can you explain why you feel the need to literally count and quantify the viability of your yeast cells?

 

No offense to you or to any of the users of this site, but if you're planning on opening a brewery and brewing 20bbl batches of anything you probably shouldn't be seeking yeast pitching advice from a site like this. Head on over to probrewer or hit the books for questions like this.

That said, at the brewery I work for, we generally pitch between 1.8 and 2 million cells per mL/per degree plato to ensure a pretty quick jumpstart on fermentation. Our lagers are generally at terminal gravity in 7-9 days.

Pitchable slurries that come from yeast labs have crazy high cell densities and are usually pitched at a volume of 1L per bbl yield in the fermentor in lagers under 16 Deg Plato. This link from wyeast does a pretty good job explaining it.

https://www.wyeastlab.com/com_b_productdetail.cfm?ProductID=14

 

Sure thing. If you want more info on SOP's/lab practice for counting cells and determining viability, shoot me a message and I'll bore you with as much as you'd like to hear!

Unfortunately, I have no way in our current lab setup to determine vitality but if you're brewing on a pretty regular schedule (2-3 day max residency of yeast in a brink) it shouldn't be much of an issue.

 

Yep! These kinds of densities are only really possible when coming directly from a yeast lab though.

The physical volume of the first generation pitch from the yeast lab will always be less than every subsequent brew because of this.