# Real Plato?

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#### Saccharomycetaceae

##### Well-Known Member
I tried posting this in the bottling forum, but didn't get any takers so I'm tryin it out here.
I want to try bottling with wort and the formula I have for figuring out how much to use involves 'real final Plato.'
Is real final Plato in contrast to apparent final Plato?
And how do I measure real final Plato?
Thanks so much for any help!
matt

#### ajdelange

##### Well-Known Member
Around the turn of the 19th century the Kaiser formed a commission under the leadership of Leo Plato whose charter was to measure the specific gravities of aqueous solutions of sucrose of various strengths to 6 (yes, 6) significant places. The strengths of the solution were specified by weight, for example a 10% solution was such that a killogram of the solution contained 100 grams of sucrose (10 grams per 100 grams). That solution had a specific gravity of about 1.040 so if you went to the tables that resulted from the Kommission's work you would find against solution strength 10% the specific gravity 1.04003. In honor of the leader the tables now show 10% as 10 °Plato. That's the background. For any value of Plato there is a specific gravity and for any specific gravity there is a Plato number and these come from tables published by the ASBC and EBC or from formulas which approximate what's in the tables.

TE = Plato_mix*(SGm/SGb).

Clearly you don't need a distillation apparatus to do this at home. You can boil or even evaporate the beer down to about 2/3 of it's original volume in any container and then quantitatively transfer back to the volumetric flask to make up to 100 mL.

OP
S

#### Saccharomycetaceae

##### Well-Known Member
Wow! That's awesome. Thanks for such a thoughtful and thorough reply. It'll be cool to work this out and see the difference.

So, using this method, I wouldn't be able to determine the real final Plato until after fermentation I take it. Is there any way to estimate what it will be before fermentation? I ask because if I want to save some wort to use for bottle conditioning, I'd want to know how much to save beforehand.
Thanks again ajdelange!