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General Category => Yeast and Fermentation => Topic started by: Wort-H.O.G. on December 09, 2014, 02:47:48 PM

Title: C.white or Kai's yeast growth models
Post by: Wort-H.O.G. on December 09, 2014, 02:47:48 PM
Don't know why i never noticed before, but using brewersfreind (http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/) , there are two stir plate growth calculations. one is Chris White's, and the other is Kai's.

Understand its just a tool and calculator for estimations ( most have no way to accurately measure starting or finishing counts), but there is a significant difference in one step growth models.

Target Profile: 1.060 Lager pitching 460B cells

Kai's Stir Plate: 1.060 lager with fresh vial of yeast with approx. 93b cells added to 3L 1.035 wort estimates 512B cells

C. White Stir Plate:  1.060 lager with fresh vial of yeast with approx. 93b cells added to 3L 1.035 wort estimates 334B cells

Kai's meets target while Chris's under pitches. What model do you use? Anyone try both with different results in finished product? 
Title: Re: C.white or Kai's yeast growth models
Post by: dkfick on December 09, 2014, 03:12:28 PM
I use Kai's.
Title: Re: C.white or Kai's yeast growth models
Post by: kramerog on December 09, 2014, 03:23:20 PM
Read this: http://braukaiser.com/blog/blog/2012/11/03/estimating-yeast-growth/

I use Kai's model for stir plates.
Title: Re: C.white or Kai's yeast growth models
Post by: theDarkSide on December 09, 2014, 03:29:17 PM
I use Kai's also because it always gives me more yeast cells  ;D
Title: Re: C.white or Kai's yeast growth models
Post by: Stevie on December 09, 2014, 03:46:04 PM
I use Kai's also because it always gives me more yeast cells  ;D


That's some good thinking.


I honestly just split the difference. I feel that Chris White has the credentials that I trust, but I have also read Kai's paper.  I read on one forum that some were suspecting Chris of low balling to sell more vials. I don't think this is the case, based solely on the fact that the vials still state one vile is good for 5 gallons of 1.070 wort.


One thing to note, Kai's calculates lower growth compared to Chris's when it comes to dense starters.
Title: Re: C.white or Kai's yeast growth models
Post by: reverseapachemaster on December 09, 2014, 04:13:22 PM
Criticism of White's advice and products seems increasingly well-founded, particularly if you are following the whole WL brett trois-isn't-brett-and-WL-knew-it thing going on right now.
Title: Re: C.white or Kai's yeast growth models
Post by: Multifaceted on December 09, 2014, 05:12:42 PM
Kai's
Title: Re: C.white or Kai's yeast growth models
Post by: denny on December 09, 2014, 05:19:10 PM
WL brett trois-isn't-brett-and-WL-knew-it thing going on right now.

Say what?
Title: Re: C.white or Kai's yeast growth models
Post by: Stevie on December 09, 2014, 05:26:26 PM
WL brett trois-isn't-brett-and-WL-knew-it thing going on right now.

Say what?
I was about to ask the same thing. I found this on reddit.


http://www.reddit.com/r/Homebrewing/comments/2ooic7/brett_trois_contains_no_brett/
Title: Re: C.white or Kai's yeast growth models
Post by: ynotbrusum on December 10, 2014, 02:34:59 AM
Bummer I had some Trois I was going to pitch, too.i had just racked onto a tart cherry wine base. This past weekend and thought I'd give it a kicker....I guess I'll just get some straight Brett instead.
Title: Re: C.white or Kai's yeast growth models
Post by: 69franx on December 10, 2014, 04:03:23 AM
Gonna have to read a bit more when on the laptop, way too small for practicality on my old iPhone w my old eyes


Sent from Franx Brew Works using Tapatalk
Title: Re: C.white or Kai's yeast growth models
Post by: erockrph on December 10, 2014, 01:58:51 PM
Bummer I had some Trois I was going to pitch, too.i had just racked onto a tart cherry wine base. This past weekend and thought I'd give it a kicker....I guess I'll just get some straight Brett instead.
IME, Trois isn't that great as a secondary yeast. Better off with something like Brett B, Brett C, Orval dregs, etc...

I'm curious in how this all plays out myself. I always thought that Brett Trois was WL's version of Brettanomyces bruxellensis var Drie. Has anyone emailed White Labs directly about this? I've never known them not to be forthcoming with information. It seems like a pretty simple way to get to the bottom of this.

Edit - I just sent an email to White Labs. I'll share any response I get.
Title: Re: C.white or Kai's yeast growth models
Post by: woodlandbrew on December 10, 2014, 07:29:23 PM
I trust Kai's model, but I might be biased.  Back when he was developing his algorithms he asked me to see if i could duplicate some of his results.  Kai's is actually based on results of starters on stir plates where C.White's is a shake flask culture experiment that was scaled up a little to account for the additional oxygen. 
Title: Re: C.white or Kai's yeast growth models
Post by: coolman26 on December 11, 2014, 03:33:27 PM
Kai, I can't go against anyone that has invested that amount of time on the homebrew scale.  I trust all of his studies.  Not that I don't trust Chris and his knowledge.  If it isn't broken, don't fix it scenario fits for me here.   
Title: Re: C.white or Kai's yeast growth models
Post by: narcout on December 11, 2014, 04:57:28 PM
Some info was posted to the White Labs website yesterday regarding WLP644.

http://www.whitelabs.com/blog/wlp644-background
Title: Re: C.white or Kai's yeast growth models
Post by: narvin on December 11, 2014, 11:31:22 PM
From what I remember, the wyeast calc seemed to produce similar results to the Chris White / Jamil models.  I'm too lazy to check right now, and I'm not saying that makes it right, just that there is some precedent.

https://www.wyeastlab.com/hb_pitchrate.cfm