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Old 12-03-2011, 07:31 AM   #21
BeerMbob
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Jan 2011
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Hello and firstly thank you for this experiment and sharing your findings.
Could you please explain how you measure the amount of yeast cells?
If a smack pack contains 1billion cells and you create a starter, how do you know when the culture will have stepped up to for example approx. 1.3 billion?
Or if I create a 2 litre starter and added the smack pack what would the cell count be?



 
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Old 12-03-2011, 07:56 AM   #22
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Yeah definitely need to subscribe to this one.


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Old 12-03-2011, 09:30 AM   #23
bigbeergeek
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Subbed... and horny.
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Old 12-03-2011, 01:48 PM   #24
phattysbox
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Jul 2009
New York City
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Hi Everyone!

Jason here, and I am the one actually doing the experiment. Glad everyone is interested in this! Currently the bottles are priming and should be ready when I poll the class by the 14th. I'll post the results soon after.

I did taste them out of the primary and they were each different. With the control pitch I thought, "ok tastes like a run of the mill blonde ale. Not bad."
The other two I went "meh..." Of course this is all very unscientific and not blinded. Before I poll the class I'll have my wife blind the samples and critique the brews. As a side note this is the first time I brewed in 1 gallon jugs and I did not use oxygen (decided to leave this variable for another day). The base beer may not be the best beer i have brewed, but hopefully the samples will be different from one another.

Thanks everyone! Feel free to post comments here. I'm more active on BA but this should change!

J

 
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Old 12-03-2011, 01:51 PM   #25
phattysbox
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Jul 2009
New York City
Posts: 51

Quote:
Originally Posted by BeerMbob View Post
Hello and firstly thank you for this experiment and sharing your findings.
Could you please explain how you measure the amount of yeast cells?
If a smack pack contains 1billion cells and you create a starter, how do you know when the culture will have stepped up to for example approx. 1.3 billion?
Or if I create a 2 litre starter and added the smack pack what would the cell count be?
So I counted the cells with a hematocytometer in the lab. Wyeast packs usually have around 100 billion or so, give or take. For the experiment I made a simple one liter starter from a very small amount of cells. About 1 million. I freeze them down and store them in aliquots at -80C so I don't have to buy smack packs

 
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Old 12-03-2011, 01:57 PM   #26
j1laskey
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May 2010
Boston
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Do you have access to a ViCell in your lab in will give your far more accurate viability counts
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Old 12-03-2011, 03:10 PM   #27
phattysbox
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Jul 2009
New York City
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Quote:
Originally Posted by j1laskey View Post
Do you have access to a ViCell in your lab in will give your far more accurate viability counts
We have something similar in the lab but its optimized for mammalian cell culture. However, I feel something like this is unnecessary. Counting in a chamber slide, if done correctly, can be extremely accurate. I have done trypan blue staining, but only for bottle dregs. My yeast that I grow in the lab are foten 95-98% viable since they are continuously stirred and stepped up appropriately.

J

 
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Old 12-03-2011, 07:21 PM   #28
bigbeergeek
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Sep 2008
Visalia, CA
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Quote:
Originally Posted by phattysbox View Post
Hi Everyone!

Jason here, and I am the one actually doing the experiment. Glad everyone is interested in this! Currently the bottles are priming and should be ready when I poll the class by the 14th. I'll post the results soon after.

I did taste them out of the primary and they were each different. With the control pitch I thought, "ok tastes like a run of the mill blonde ale. Not bad."
The other two I went "meh..." Of course this is all very unscientific and not blinded. Before I poll the class I'll have my wife blind the samples and critique the brews. As a side note this is the first time I brewed in 1 gallon jugs and I did not use oxygen (decided to leave this variable for another day). The base beer may not be the best beer i have brewed, but hopefully the samples will be different from one another.

Thanks everyone! Feel free to post comments here. I'm more active on BA but this should change!

J
Thanks for sharing your experiment with us!
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Old 12-03-2011, 07:53 PM   #29
MrManifesto
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Apr 2011
Brooklyn, NY
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Quote:
Originally Posted by phattysbox
Hi Everyone!

Jason here, and I am the one actually doing the experiment. Glad everyone is interested in this! Currently the bottles are priming and should be ready when I poll the class by the 14th. I'll post the results soon after.

I did taste them out of the primary and they were each different. With the control pitch I thought, "ok tastes like a run of the mill blonde ale. Not bad."
The other two I went "meh..." Of course this is all very unscientific and not blinded. Before I poll the class I'll have my wife blind the samples and critique the brews. As a side note this is the first time I brewed in 1 gallon jugs and I did not use oxygen (decided to leave this variable for another day). The base beer may not be the best beer i have brewed, but hopefully the samples will be different from one another.

Thanks everyone! Feel free to post comments here. I'm more active on BA but this should change!

J
Uhhhh wow, world is a small place! Looking forward to your class, see you on the 14th!

 
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Old 12-03-2011, 08:01 PM   #30
mcaple1
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Apr 2011
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sub'd



 
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