Author Topic: Stalled Fermentation - Belgian Strong  (Read 2116 times)

Offline ukolowiczd

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Re: Stalled Fermentation - Belgian Strong
« Reply #15 on: October 14, 2011, 02:15:14 PM »
How does one do that - count yeast under the microscope - I'd love to try it?

http://www.whitelabs.com/beer/microscope.html

Thanks, what a great resource. What kind of dye do you use? Methylene blue? Is it necessary? I'll look up those Hemo-whatever slides on line.

Offline tschmidlin

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Re: Stalled Fermentation - Belgian Strong
« Reply #16 on: October 14, 2011, 04:43:34 PM »
How does one do that - count yeast under the microscope - I'd love to try it?

http://www.whitelabs.com/beer/microscope.html

Thanks, what a great resource. What kind of dye do you use? Methylene blue? Is it necessary? I'll look up those Hemo-whatever slides on line.
The gram staining in those pics is for identification.  Methylene blue or methylene violet is typically used for viability staining.  If you are just counting cells, you don't need a stain.
Tom Schmidlin

Offline richardt

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Re: Stalled Fermentation - Belgian Strong
« Reply #17 on: October 14, 2011, 09:38:51 PM »
1.092 to 1.025 = 78% App. Attenuation

Wyeast gives the attenuation range of 1388 as 73-78%

1.016 will get you to the upper end of the FG (and ABV) of the BJCP guideline, which is about 83% attenuation....

I get a different result.  I get almost 73% apparent attenuation, not 78%.

   Apparent Attenuation in % = 100 * (OG – FG)/(OG – 1.0).

   Apparent Attenuation (%)   = 100 * (1.092 - 1.025)/(1.092 - 1.0).

   Apparent Attenuation (%)   = 100 * 67/92  =  72.8%

I would give it another week or two in the fermentor (re-rouse, if you wish) to finish up and then bottle and/or chill to clear then keg.

You may want to split batch if you're entertaining the idea of adding Brett, i.e., don't add it to the whole batch.

Offline jjflash

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Re: Stalled Fermentation - Belgian Strong
« Reply #18 on: October 19, 2011, 08:41:56 PM »
How does one do that - count yeast under the microscope - I'd love to try it?

http://www.whitelabs.com/beer/microscope.html

Thanks, what a great resource. What kind of dye do you use? Methylene blue? Is it necessary? I'll look up those Hemo-whatever slides on line.
I use methylene blue - two drops in the final dilution.  Those yeast cells that stain dark blue are non-viable cells, I do not count them. Yes, I consider the dye important if I am doing an accurate cell count.  You never know when the vial/package of yeast you just bought has been poorly handled and the yeast have suffered a terminal event.
---JJ---

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