Author Topic: Post Boil Volume  (Read 92 times)

Offline kbonura

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Post Boil Volume
« on: October 10, 2019, 06:55:26 PM »
Hey guys, I'm a little confused about what the intended interpretation of the kettle volumes are.

Pre Boil volume is taken at temperature... That makes sense.
My question...
Does post boil volume get measured at knock out (measured hot)?
Also does post boil volume take into account chiller / trub loss?

I ask b/c my post boil volume (hot) was more then predicted... However post boil after chilling was near spot on... Not sure what was intended.

Read an older post explaining some of this but it somewhat confused me.
Basically need to know post boil = volume after flame out (with or without taking  into account trub / chiller losses)...
Thanks in advance!

Offline GigaFemto

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Re: Post Boil Volume
« Reply #1 on: October 11, 2019, 10:56:54 AM »
My question...
Does post boil volume get measured at knock out (measured hot)?

Yes. Look at the Volumes tab and you can see that: (Post Boil Volume) - (Cooling shrinkage) - (trub loss) + (Top up water) = batch size

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Offline kbonura

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Re: Post Boil Volume
« Reply #2 on: October 12, 2019, 05:08:07 AM »
Ok, so that doesn't include trub loss in its value correct?

I often run my chiller loop prior to the end of the boil just to sanitize and purge the O2. Need to make sure I'm appropriately accounting for my volumes.

Thanks for the response!

Online Oginme

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Re: Post Boil Volume
« Reply #3 on: October 12, 2019, 05:47:17 AM »
Post boil volume is the total volume of wort remaining when the flame or heat is turned off at the end of the boil.  This includes all wort in the kettle, in piping, or removed from the pot during the boil with intent to pour it back in. 

Given this, as GigaFemto had pointed out, the post boil volume contains all wort intended for the fermenter, all wort which will remain in the kettle, all wort which is in piping or pump, all wort which has been removed for testing, and all wort which gets spilled during any transfers.  In BeerSmith, this volume also includes the thermal expansion based upon the temperature of the wort at boiling.

You can follow all the calculations on the volumes tab of your recipe to see where the volumes are accounted for and where the program switches (when following from the fermenter backwards as the program calculates it) from cold measured volumes to hot volumes. 

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