### Author Topic: Why Plato?  (Read 20550 times)

#### ccfoo242

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##### Why Plato?
« on: July 03, 2013, 08:02:46 pm »
Why is it pro brewers use plato for beginning and ending measurements instead of specific gravity?

Do pro brewers use a different instrument than a hydrometer?
Intra cervisiam est deus.

#### jamminbrew

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##### Re: Why Plato?
« Reply #1 on: July 03, 2013, 10:12:11 pm »
"°Plato = percent extract (or "sugar", although it's not all sugar) by weight in solution. So, 10°P = 10% extract by weight. This makes things easy for brewing calculations.

Specific gravity relates to (instead of weight of extract) the weight of the whole volume of solution relative to an equal volume of water. So, a 1.060 volume of wort is 6% heavier than the same volume of water."

I got this from:
http://www.homebrewtalk.com/f14/plato-vs-specific-gravity-117065/

I hope this helps?

Edit: We use a refractometer during sparge, pre and post-boil, and to ascertain our OG.  Hydrometer to check during fermentation, and FG.
« Last Edit: July 04, 2013, 07:26:14 am by jamminbrew »
In caelo cerivisiae nil, hic igitur bibimus.

#### dmtaylor

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##### Re: Why Plato?
« Reply #2 on: July 04, 2013, 06:33:05 am »
My bet is they still use Plato for a couple of reasons:

1) They've always done it that way for hundreds of years, and

2) In their mind it might be a little easier to deal with than a bunch of ones and decimal points and zeroes.  Just easier to write down and keep track of and so forth than a bunch of extra digits.

To each their own.  I prefer specific gravity because for a 1.060 beer I know I can lop off the 1.0 and add a decimal point to get approximately a 6.0% ABV beer.  But the pros will say, that's easy -- it's a 15 Plato beer, so just multiply by 4 and throw in the decimal point to get the same ABV potential.  Personally I think not having to multiply by 4 makes life a lot easier.  But whatever.
Dave

The world will become a much more pleasant place to live when each and every one of us realizes that we are all idiots.

#### cheshirecat

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##### Re: Why Plato?
« Reply #3 on: July 04, 2013, 10:07:59 am »
I would also add that it is probably easier on brew day using a couple drops of wort on a refractometer vs filling hydrometer every time you wanted to check the gravity. Less worries about temp etc.

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#### klickitat jim

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##### Re: Why Plato?
« Reply #4 on: July 04, 2013, 10:58:58 am »
I'm not sure, but its just 0957 hrs and I haven't woke up yet

#### dmtaylor

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##### Re: Why Plato?
« Reply #5 on: July 05, 2013, 08:49:41 am »
I would also add that it is probably easier on brew day using a couple drops of wort on a refractometer vs filling hydrometer every time you wanted to check the gravity. Less worries about temp etc.

Cheshirecat is also right, but this still begs the question: Why couldn't the refractometer manufacturers have their meters read out in units of SG rather than Brix or Plato?  How did they select the standard units?  Maybe it's a wine thing?  But why couldn't wine guys use SG also??

No matter how you look at it, I think it's just people too set in their old ways of doing things.
Dave

The world will become a much more pleasant place to live when each and every one of us realizes that we are all idiots.

#### Jimmy K

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##### Re: Why Plato?
« Reply #6 on: July 05, 2013, 10:39:34 am »
I says to myself - I'm sure there is a SG refractometer out there. Sure enough - dual scale ...

http://www.amazon.com/Beer-Wort-Wine-Refractometer-Scale/dp/B006GG0TDK

AND IT'S ON SALE FOR \$15 (from \$90). SCORE!!!
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#### morticaixavier

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##### Re: Why Plato?
« Reply #7 on: July 05, 2013, 10:56:57 am »
I says to myself - I'm sure there is a SG refractometer out there. Sure enough - dual scale ...

http://www.amazon.com/Beer-Wort-Wine-Refractometer-Scale/dp/B006GG0TDK

AND IT'S ON SALE FOR \$15 (from \$90). SCORE!!!

I actually just grabbed one as well. did I  need it? nah but it's a darn good deal
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#### dmtaylor

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##### Re: Why Plato?
« Reply #8 on: July 05, 2013, 11:40:00 am »
Pretty sweet, HOWEVER.... I considered buying one myself, until I read the reviews that said the SG scale is quite a bit off.  The Brix scale reads right though apparently.  But if it can't read the SG scale right, then I don't want one.
Dave

The world will become a much more pleasant place to live when each and every one of us realizes that we are all idiots.

#### Jimmy K

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##### Re: Why Plato?
« Reply #9 on: July 05, 2013, 11:46:39 am »
Technically, I think that's because a refractometer can't directly read SG. And the problem is the relationship between SG and Plato are not perfectly linear. For the same reason, a hydrometer can't directly read Plato.
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#### punatic

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##### Re: Why Plato?
« Reply #10 on: July 05, 2013, 01:11:10 pm »
Because Plato was way smarter and much more philisophical than Specfic Gravity and Mr. Brix.  I mean Plato's teacher was Socrates for cryin' out loud!   That just screams beer!
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#### klickitat jim

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##### Re: Why Plato?
« Reply #11 on: July 05, 2013, 01:13:56 pm »
Pronounced So-Crates and he hated Say-Zon

#### ccfoo242

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• I drank what? - Socrates
##### Re: Why Plato?
« Reply #12 on: July 05, 2013, 05:07:07 pm »
Technically, I think that's because a refractometer can't directly read SG. And the problem is the relationship between SG and Plato are not perfectly linear. For the same reason, a hydrometer can't directly read Plato.

So when a brewery gives starting and finishing plato, which instrument gives them that? Refractometers give degrees Brix and hydrometers give specific gravity. What gives plato?
Intra cervisiam est deus.

#### punatic

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##### Re: Why Plato?
« Reply #13 on: July 05, 2013, 05:07:36 pm »
Pronounced So-Crates and he hated Say-Zon
But he loved Ply Knee the Elder!
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#### Pawtucket Patriot

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##### Re: Why Plato?
« Reply #14 on: July 05, 2013, 06:30:24 pm »
Technically, I think that's because a refractometer can't directly read SG. And the problem is the relationship between SG and Plato are not perfectly linear. For the same reason, a hydrometer can't directly read Plato.

So when a brewery gives starting and finishing plato, which instrument gives them that? Refractometers give degrees Brix and hydrometers give specific gravity. What gives plato?

Brix = Plato
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