Electric Brewing Supply 30A BCS Giveaway!


Home Brew Forums > Home Brewing Beer > Fermentation & Yeast > MrMalty Caculator - Are the vials to volume ratios linear?
Reply
 
LinkBack Thread Tools
Old 12-12-2012, 09:06 PM   #21
zeg
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2012
Location: West Lafayette, IN
Posts: 1,218
Liked 128 Times on 110 Posts
Likes Given: 137

Default

Quote:
Originally Posted by jtkratzer View Post
If I go that route, does this work? 1.5 liter starter, stepped to a 3 liter, makes roughly 650 billion cells. Split it in half - 1.5 liters gets split into the two fermenters of CB, the other 1.5 liters gets decanted and 2.5 liters of wort dumped onto it and the calculator puts me at 650 billion again for my 590 needed for the porter.
I'm not checking your numbers here, but this sounds generally feasible.

You'll want to give yeast viability some thought, though. Even storing yeast in the fridge, it fades fairly rapidly. The easiest (and only) way I know to estimate this is to play with the MrMalty calculator "slurry" tab and set the collection date to various times in the past. Rule of thumb seems to be you'd like to keep the viability at over 90%, but I think that's less of an issue if you're going to do another starter instead of simply repitching.
__________________
zeg is offline
 
Reply With Quote Quick reply to this message
Old 12-12-2012, 09:40 PM   #22
WoodlandBrew
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
WoodlandBrew's Avatar
Recipes 
 
Join Date: Oct 2012
Location: Malden, MA
Posts: 1,771
Liked 123 Times on 120 Posts
Likes Given: 57

Default

Don't sweat the small stuff.

Yeast Calc and Mr. Malty show you three significant figures so you can see how things work, but in reality growth rates can vary quite a bit. You have to be off by quite a bit to really make a difference. Like a factor of five.

Viability in the fridge doesn't change much over time. I have a slurry that I have been doing cell counts on for a month and the viability has remained virtually the same for the whole time. The real wild card is knowing how much you are starting with. Depending on density and viability (neither of which can be determined without a microscope) the viable cell count can range from 100 million to 2 trillion cells per liter. A white labs vial is within 10% of 100 billion cells from counts I have done.

You should have no problem splitting the starter for two beers. Give is a little good swirl or a shake to homogenization it and you should be fine.

Here is some information on Mr. Malty:
http://woodlandbrew.blogspot.com/201...ing-cells.html

__________________

The 2nd edition is now available: Brewing Engineering
Woodland Brewing Research Blog Applied Science for Better Beer.

WoodlandBrew is offline
 
Reply With Quote Quick reply to this message
Old 12-12-2012, 11:25 PM   #23
zeg
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2012
Location: West Lafayette, IN
Posts: 1,218
Liked 128 Times on 110 Posts
Likes Given: 137

Default

[quote=WoodlandBrew;4676524]Yeast Calc and Mr. Malty show you three significant figures so you can see how things work, but in reality growth rates can vary quite a bit. You have to be off by quite a bit to really make a difference. Like a factor of five.[QUOTE]
Agree completely. If it needed to be any more accurate than this, none of us would have consistent success fermenting anything.

Quote:
Viability in the fridge doesn't change much over time. I have a slurry that I have been doing cell counts on for a month and the viability has remained virtually the same for the whole time.
Your results are interesting. Any thoughts on why your results disagree so wildly (apparently, anyway) with those that led to the models used by the calculators? Yours are interesting data points, but I'm curious how extensive the other set of experiments are. Otherwise it's hard to determine whether your findings are generally applicable or outliers for some reason.
__________________
zeg is offline
 
Reply With Quote Quick reply to this message
Old 12-12-2012, 11:39 PM   #24
TTB
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2012
Posts: 44
Liked 6 Times on 3 Posts
Likes Given: 2

Default

Quote:
Originally Posted by jkendal View Post
I have a 10-gallon system. When I use liquid yeast I start with a 2L starter and then the next evening step it up to 4L. I get excellent results every time.
How do you step it up the next evening? Just add more wort? No, cooling and decanting?
__________________
TTB is offline
 
Reply With Quote Quick reply to this message
Old 12-12-2012, 11:46 PM   #25
WoodlandBrew
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
WoodlandBrew's Avatar
Recipes 
 
Join Date: Oct 2012
Location: Malden, MA
Posts: 1,771
Liked 123 Times on 120 Posts
Likes Given: 57

Default

Zeg,

You've got the right idea. It's good to be curious about validity of information that you hear. As I'm sure you know, there is quite a bit of misinformation all around, even on this forum. Unfortunately perfect data is a fantasy, and every experiment and conclusion has flaws when it comes down to practical application.

I've been tracking a total of nine slurries over the last month and collected 65 data points. The Mr. Malty calculation is really just a rough estimate.


From the Mr. Malty site:

Quote:
The bad thing is that you can't tell how viable that yeast is, unless you have the equipment to properly test and count it. So this is where it gets a little bit like black magic.
You can read it all here:
http://www.mrmalty.com/pitching.php

I don't think there is anything special about my slurries that makes them not loose 1.5% viability per day that the Mr. Malty calculator shows. My weakest slurry was 8% viability a month ago and is 8% today. If the Mr. Malty slurry calculator was right I would not be able to find a single live cell in it. I'm just saying that the slurry viability an estimation at best, but perhaps just a swag. I would not be surprised to learn that Jamil came up with the equations that the estimate slurry viability by taking a pole of respected brewers, asking how old of a slurry they would use and then just made the calculator show zero percent viability at that time.

In my experience there are many much larger factors involved in viability than the amount of time it has been in the fridge.
__________________

The 2nd edition is now available: Brewing Engineering
Woodland Brewing Research Blog Applied Science for Better Beer.

WoodlandBrew is offline
 
Reply With Quote Quick reply to this message
Old 12-13-2012, 11:08 AM   #26
zeg
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2012
Location: West Lafayette, IN
Posts: 1,218
Liked 128 Times on 110 Posts
Likes Given: 137

Default

Quote:
Originally Posted by WoodlandBrew View Post
Unfortunately perfect data is a fantasy, and every experiment and conclusion has flaws when it comes down to practical application.
Well, I'm not thinking about "perfect data," just trying to understand the limitations of your (and others') experiments.

Quote:
I've been tracking a total of nine slurries over the last month and collected 65 data points.
Are they nine identical slurries, or are they different strains/conditions/something? How are you storing them?


Quote:
I would not be surprised to learn that Jamil came up with the equations that the estimate slurry viability by taking a pole of respected brewers, asking how old of a slurry they would use and then just made the calculator show zero percent viability at that time.

In my experience there are many much larger factors involved in viability than the amount of time it has been in the fridge.
Given the rigor that Jamil has otherwise applied to understand yeast, I guess that would surprise me. While he also points out the importance of storage conditions and yeast strain as important, it'd seem out of character for a meaningless guess to be included. Given the acknowledged importance of factors other than age, it doesn't seem unlikely that various studies might disagree pretty widely without any of them being incorrect.
__________________
zeg is offline
 
Reply With Quote Quick reply to this message
Old 12-13-2012, 12:02 PM   #27
WoodlandBrew
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
WoodlandBrew's Avatar
Recipes 
 
Join Date: Oct 2012
Location: Malden, MA
Posts: 1,771
Liked 123 Times on 120 Posts
Likes Given: 57

Default

Quote:
Originally Posted by zeg View Post
Are they nine identical slurries, or are they different strains/conditions/something? How are you storing them?
They are from 3 different batches of beer. Three pours each representitive of the top, middle and bottom of the cake. Stored in the fridge in mason jars like most people seem to do.


Quote:
Originally Posted by zeg View Post
Given the acknowledged importance of factors other than age, it doesn't seem unlikely that various studies might disagree pretty widely without any of them being incorrect.
You got it. That's exactly my point: The viability by date varies widely because there are other much larger factors than date.
__________________

The 2nd edition is now available: Brewing Engineering
Woodland Brewing Research Blog Applied Science for Better Beer.

WoodlandBrew is offline
 
Reply With Quote Quick reply to this message
Old 12-19-2012, 02:35 PM   #28
jkendal
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2012
Location: Burton, TX
Posts: 219
Liked 12 Times on 9 Posts
Likes Given: 1

Default

Quote:
Originally Posted by TTB View Post
How do you step it up the next evening? Just add more wort? No, cooling and decanting?
Sorry, just now saw this (been away for a week doing other things - horrible on my part, I know...)

I usually make my starters in 1-gallon wine jugs. My Dad likes Gallo Burgundy in the big gallon jugs and gives me the empties. They're great for starters - especially for what I call 2-stage starters...

First night - 2 qt starter as normal - cool it and pitch into the gallon jug.

Second night - make another 2 qt starter, cool it and add it to the gallon jug. Sometimes I might have to decant just a little to get it all to fit - no need to leave a bunch of head space as not much krausen forms in starters.

I found that doing it this way yields a bit more yeast than just pitching an entire 4 qt starter.

Then on brew day you can decant and split just the yeast cake between the 2 fermenters. Sometimes I just shake the whole thing and split it.

Hope this helps.
__________________

We've got provisions and lots of beer
The key word is survival on the new frontier
~ Donald Fagen

jkendal is offline
 
Reply With Quote Quick reply to this message
Old 12-19-2012, 02:51 PM   #29
zeg
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2012
Location: West Lafayette, IN
Posts: 1,218
Liked 128 Times on 110 Posts
Likes Given: 137

Default

Quote:
Originally Posted by jkendal View Post
Sometimes I might have to decant just a little to get it all to fit - no need to leave a bunch of head space as not much krausen forms in starters.
Just be careful if you're doing intermittent shaking---I've had a couple overflows due to foaming when I shake them even a little bit!

Incidentally, I've been doing starters in gallon jugs much like you describe. Mine are cider jugs, but they're probably the same as the wine jugs. For the high gravity lagers I've been doing, I have had to use two of them, though. My plan for the next one, starting from about 10 mL of rinsed yeast slurry, is to start with a 500 mL step, then do a 3L step, and then split that into two jugs and do 3L in each. This multistep business seems to help compensate for uncertainty in the number of cells you start with, at least if you trust the calculators.
__________________
zeg is offline
 
Reply With Quote Quick reply to this message
Old 12-19-2012, 06:11 PM   #30
jkendal
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2012
Location: Burton, TX
Posts: 219
Liked 12 Times on 9 Posts
Likes Given: 1

Default

Quote:
Originally Posted by zeg View Post
Just be careful if you're doing intermittent shaking---I've had a couple overflows due to foaming when I shake them even a little bit!

Incidentally, I've been doing starters in gallon jugs much like you describe. Mine are cider jugs, but they're probably the same as the wine jugs. For the high gravity lagers I've been doing, I have had to use two of them, though. My plan for the next one, starting from about 10 mL of rinsed yeast slurry, is to start with a 500 mL step, then do a 3L step, and then split that into two jugs and do 3L in each. This multistep business seems to help compensate for uncertainty in the number of cells you start with, at least if you trust the calculators.
Are you brewing a 10-gallon batch? That's a lot of yeast...
__________________

We've got provisions and lots of beer
The key word is survival on the new frontier
~ Donald Fagen

jkendal is offline
 
Reply With Quote Quick reply to this message
Reply



Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pneumatic Linear Actuators CoalCracker DIY Projects 3 09-19-2012 05:08 PM
Do recipe's scale up or down in a linear way? davekippen General Beer Discussion 3 08-10-2012 11:22 PM
Mash water volume ratios. Brewpastor All Grain & Partial Mash Brewing 37 09-21-2011 07:57 PM
MrMalty - Two vials - Two Different Viability Dates yournotpeter Fermentation & Yeast 3 08-11-2010 08:58 AM
gravity and volume - linear ? kappclark All Grain & Partial Mash Brewing 6 11-13-2007 12:28 AM