Ss Brewing Technologies Giveaway!

Home Brew Forums > Home Brewing Beer > Fermentation & Yeast > Viability Calculations with different calculators
Reply
 
LinkBack Thread Tools
Old 02-19-2013, 10:23 PM   #1
mclaughlindw4
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2012
Posts: 194
Liked 6 Times on 5 Posts
Likes Given: 3

Default Viability Calculations with different calculators

I am currently comparing yeast calc to mr.malty. I put in a production date of 11/18/2012. Yeastcalc gives me 60% viability and Mr.Malty gives me 30%

So I made a 1.5 L starter for a 1.041 OG beer. According to Mr.Malty I am right on with my counts but according to Yeastcalc I overpitched by 60 billion cells (or about 36%). Now I am concerned I may have overpitched which would be a bummer because I am making a saison.

The weird thing is, I used yeast calc the other day and I swear it gave me 30% and not 60%. Am I just going crazy?

I have searched through threads and read both sites as well as wyeast and white labs sites for faq and can find very little info on this topic.

__________________
mclaughlindw4 is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 01:59 AM   #2
Kaiser
Feedback Score: 0 reviews
 
Kaiser's Avatar
Recipes 
 
Join Date: Nov 2005
Location: Pepperell, MA
Posts: 3,904
Liked 114 Times on 71 Posts
Likes Given: 4

Default

Don't put to much trust into these yeast calculators. there are many factors for yeast growth that are not considered. I also think that the Mr malty calculator underestimates yeast growth in stirred starters for lower innoculation rates.

Kai

Kaiser is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 02:33 AM   #3
mclaughlindw4
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2012
Posts: 194
Liked 6 Times on 5 Posts
Likes Given: 3

Default

I can find tons of info about pitching rates, growth rates, etc, and I suppose I could do my own calculations in this respect. But if I don't know what baseline I am starting with then everything else is meaningless.

Wyeast and white labs have basically no info (that I could find) about viability of their product as it ages. Wyeast basically says you don't need a starter, unless you do. Mr.Malty and YeastCalc tell you nothing about how they came up with the calculations they use (for viability), in addition to the fact that the do not agree with eachother.

I am just looking for some guidance or opinions on how to determine viability of my yeast, as this seems to me like it would be the basis for attempting to get the right pitch rate.

__________________
mclaughlindw4 is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 05:14 AM   #4
iaefebs
HBT_SUPPORTER.png
Feedback Score: 2 reviews
 
iaefebs's Avatar
Recipes 
 
Join Date: Aug 2010
Location: West Coast, MI
Posts: 2,644
Liked 239 Times on 173 Posts
Likes Given: 602

Default

This may not be the correct timeline, but it is how I saw this issue evolve over the last couple years. 1st thing to happen was White labs and Wyeast sold yeast to us homebrewers in 5 gallon pitchable containers. Everyone was happy. Then Jamil started to say that we needed more yeast cells and argued for a higher pitch rate and came up with a online calculator.. Chris White, didn't agree and asked for homebrewers input. Beersmith was using it's own calculations. Chris and Jamil then eventualy collaborated to write a book together. If you get the book "Yeast" by Chris White and Jamil Zainasheff it has great information. That left Beersmith and MR Malty at odds with each other and Beersmith challenged Mr Malty saying their formula was more accurate. Now Beersmith and Mr Malty agree, Beersmith uses Mr Malty calculations. I didn't come across YeastCalc till late in the game when I started doing step starters, viewing past history I'm going to guess that one day YeastCalc will agree on the viability issue. I use Beersmith and Mr malty for my 1st step and use Yeastcalc for the next steps. I could use Mr Malty or Beersmith for step starters but YeastCalc looks easier. Until I actually decide to start doing my own cell counts I have a blind faith in the people that have done the previous research. What I try to keep in mind is that we brewed some great beers back in the day when you pitched a vial or smack pack just by getting the freshest yeast at the LHBS. Some of the members here have gotten into cell counting and maybe they can offer some additional info on non laboratory results.

__________________

Baseball is purer than life; it's symmetrical, fair, and dignified. There's no debating what happened: it happened.
MARVIN COHEN

iaefebs is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 01:24 PM   #5
Kaiser
Feedback Score: 0 reviews
 
Kaiser's Avatar
Recipes 
 
Join Date: Nov 2005
Location: Pepperell, MA
Posts: 3,904
Liked 114 Times on 71 Posts
Likes Given: 4

Default

This gives some insight into the work I'm doing right now: http://braukaiser.com/blog/blog/2012...-yeast-growth/

The problem with the yeast calculators out there is that there is very little information on the research that supports their models. To my knowledge there are 2 major sources: White/Zainacheff and Wyeast. I asked both if they used stir plates for their stirred starter curves and did not get an answer back. Because still and stirred starters behave differently when it comes to yeast growth one cannot derive the "stirred starter" curve by extrapolating the non stirred starter curve. You really have to do a lot of stirred starters and that's a bit more resource and time intensive than simply using an array if non agitated starters inoculated with different amounts of yeast.

mclaughlindw4, I put your data into the Brewer's Friend yeast calculator, which implements my model, and I get about 290 Billion cells if I assume that the yeast in the vial is about 50% viable. That's just another point for you.

As for assessing yeast amount w/o counting, try weighing the slurry. Simply note the empty weight of the flask and the weight of the stir bar. Then when the yeast has settled decant the starter beer and weigh the flask. Ale yeasts like WLP001 have about 2-3 Billion cells per gram sediment. Lager yeasts are more like 4-5 B/g. WLP 002 also has about 4-5 B/g. I'm still working on refining these numbers and include more strains.

Kai

Kaiser is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 04:17 PM   #6
iaefebs
HBT_SUPPORTER.png
Feedback Score: 2 reviews
 
iaefebs's Avatar
Recipes 
 
Join Date: Aug 2010
Location: West Coast, MI
Posts: 2,644
Liked 239 Times on 173 Posts
Likes Given: 602

Default

If I remember correctly, when Beersmith 2.0 first came out the differences in the calculators was for the growth factor on a stir plate. MrMalty used less than 2 and Beersmith used greater than 2.5. I know that Brad and Jamil got together on this.

__________________

Baseball is purer than life; it's symmetrical, fair, and dignified. There's no debating what happened: it happened.
MARVIN COHEN

iaefebs is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 04:59 PM   #7
mclaughlindw4
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2012
Posts: 194
Liked 6 Times on 5 Posts
Likes Given: 3

Default

Ok thanks everyone! Lots of good info to think about.

__________________
mclaughlindw4 is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 05:24 PM   #8
Kaiser
Feedback Score: 0 reviews
 
Kaiser's Avatar
Recipes 
 
Join Date: Nov 2005
Location: Pepperell, MA
Posts: 3,904
Liked 114 Times on 71 Posts
Likes Given: 4

Default

Quote:
Originally Posted by iaefebs
If I remember correctly, when Beersmith 2.0 first came out the differences in the calculators was for the growth factor on a stir plate. MrMalty used less than 2 and Beersmith used greater than 2.5. I know that Brad and Jamil got together on this.
thanks for that info. Do you know how this growth rate is defined? I.e what do the 2 and 2.5 mean?

Kai
__________________
BrauKaiser.com - brewing science blog - Twitter - water and mash chemistry calculator
Kaiser is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 05:40 PM   #9
thadius856
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
thadius856's Avatar
Recipes 
 
Join Date: Dec 2012
Location: Marysville
Posts: 2,270
Liked 565 Times on 250 Posts
Likes Given: 155

Default

Quote:
Originally Posted by mclaughlindw4 View Post
Wyeast and white labs have basically no info (that I could find) about viability of their product as it ages. Wyeast basically says you don't need a starter, unless you do. Mr.Malty and YeastCalc tell you nothing about how they came up with the calculations they use (for viability), in addition to the fact that the do not agree with eachother.
Wyeast gives out this information, just in an odd way. They have both a homebrewer and a commercial customer base. They seem to feel the need to dumb down the science of the Activator smack packs to make their product more accessible to less experienced brewers. Guess what, it works. I went through at least 5 packs of 1056 before I realized I could get by with US-05 cheaper and without a starter.

The advanced information is out there from Wyeast, you just have to go to their commercial version of the site. Here's a very good interview... a full hour of nothing but yeast. Super informative. Make sure to pause at times when information starts to get thick.


As for a baseline, they state that they measure the cell count on each batch, then concentrate or dilute to get you 100 billion cells in each Activator pack on packaging day. They don't provide viability information that I know of, probably because it's strain-dependent and based more on how it's handled than anything else.

White Labs, from best I know, is 75 - 150b cells per vial. Makes no sense to me that they'd do that. All my vials have been about 35% solids by volume, which is odd, because of the great variability in the solids sizes of each strain.
__________________
Was this post helpful? Don't forget to click 'Like'!

Thadius Miller, Project Manager -> RaspberryPints

Before you build a keezer, look at this!
Chest Freezer Spec Sheets and Layout Drawings (15 models and counting)
thadius856 is offline
 
Reply With Quote Quick reply to this message
Old 02-20-2013, 09:07 PM   #10
highgravitybacon
Feedback Score: 0 reviews
Recipes 
 
Join Date: Sep 2012
Posts: 895
Liked 203 Times on 142 Posts
Likes Given: 151

Default

I wonder about this topic. Maybe its more fuss than necessary. Clearly too little yeast is bad, too much yeast bad also. But yeast are adaptable. How too few is really To Few? Same with too much? What is the fat part of the curve where it really doesn't matter?

If you brew varied beers, with different yeast strains, are the calculators going to even be comparable? I dont think in these cases it is.

__________________
highgravitybacon is offline
Jayhem Likes This 
Reply With Quote Quick reply to this message
Reply



Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
ABV Calculators RickCov Wine Making Forum 7 05-28-2011 06:39 AM
Keg calculators. Schnitzengiggle Bottling/Kegging 4 04-18-2010 05:45 PM
Calculators ALF Brew Science 0 03-24-2010 03:54 AM
Efficiency calculators? telebrewer All Grain & Partial Mash Brewing 3 06-09-2009 02:25 PM
calculators makingitgood General Beer Discussion 2 01-02-2006 09:10 PM