### Author Topic: Why Plato?  (Read 6743 times)

#### ccfoo242

• Brewmaster
• Posts: 710
• I drank what? - Socrates
##### Why Plato?
« on: July 03, 2013, 07:02:46 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

• Brewmaster
• Posts: 760
• theAntipunk
##### Re: Why Plato?
« Reply #1 on: July 03, 2013, 09:12:11 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, 06:26:14 AM by jamminbrew »
Member, AHA
Member, Brew Brothers of Pikes Peak
BJCP judge# D1248
In caelo cerivisiae nil, hic igitur bibimus.

#### dmtaylor

• Brewmaster
• Posts: 640
##### Re: Why Plato?
« Reply #2 on: July 04, 2013, 05:33:05 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

"This is grain, which any fool can eat, but for which the Lord intended a more divine means of consumption. Let us give praise to our Maker, and glory to His bounty, by learning about... BEER!" - Friar Tuck (Robin Hood - Prince of Thieves)

#### cheshirecat

• Assistant Brewer
• Posts: 222
##### Re: Why Plato?
« Reply #3 on: July 04, 2013, 09:07:59 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.

Sent from my iPad using Tapatalk HD

#### klickitat jim

• Senior Brewmaster
• Posts: 1518
##### Re: Why Plato?
« Reply #4 on: July 04, 2013, 09:58:58 AM »
I'm not sure, but its just 0957 hrs and I haven't woke up yet

#### dmtaylor

• Brewmaster
• Posts: 640
##### Re: Why Plato?
« Reply #5 on: July 05, 2013, 07:49:41 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

"This is grain, which any fool can eat, but for which the Lord intended a more divine means of consumption. Let us give praise to our Maker, and glory to His bounty, by learning about... BEER!" - Friar Tuck (Robin Hood - Prince of Thieves)

#### mtnrockhopper

• Brewmaster General
• Posts: 2316
• Delaware
##### Re: Why Plato?
« Reply #6 on: July 05, 2013, 09:39:34 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!!!
Jimmy K
Flukes Craft Ales (not commercial)
Delmarva United Homebrewers - president by mob election
AHA Member since uhh, well, it's been years anyway
Newly annointed BJCP judge

#### morticaixavier

• Official Poobah of No Life.
• Posts: 4750
• Davis, CA
##### Re: Why Plato?
« Reply #7 on: July 05, 2013, 09:56:57 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
"Creativity is the residue of wasted time" - A. Einstein

Jonathan I Fuller

#### dmtaylor

• Brewmaster
• Posts: 640
##### Re: Why Plato?
« Reply #8 on: July 05, 2013, 10:40:00 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

"This is grain, which any fool can eat, but for which the Lord intended a more divine means of consumption. Let us give praise to our Maker, and glory to His bounty, by learning about... BEER!" - Friar Tuck (Robin Hood - Prince of Thieves)

#### mtnrockhopper

• Brewmaster General
• Posts: 2316
• Delaware
##### Re: Why Plato?
« Reply #9 on: July 05, 2013, 10:46:39 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.
Jimmy K
Flukes Craft Ales (not commercial)
Delmarva United Homebrewers - president by mob election
AHA Member since uhh, well, it's been years anyway
Newly annointed BJCP judge

#### punatic

• Official Poobah of No Life.
• Posts: 4410
• Puna District, Hawaii Island (UTC -10)
##### Re: Why Plato?
« Reply #10 on: July 05, 2013, 12:11:10 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!
There is only one success: to be able to spend your life in your own way.

AHA Life Member #33907

#### klickitat jim

• Senior Brewmaster
• Posts: 1518
##### Re: Why Plato?
« Reply #11 on: July 05, 2013, 12:13:56 PM »
Pronounced So-Crates and he hated Say-Zon

#### ccfoo242

• Brewmaster
• Posts: 710
• I drank what? - Socrates
##### Re: Why Plato?
« Reply #12 on: July 05, 2013, 04:07:07 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

• Official Poobah of No Life.
• Posts: 4410
• Puna District, Hawaii Island (UTC -10)
##### Re: Why Plato?
« Reply #13 on: July 05, 2013, 04:07:36 PM »
Pronounced So-Crates and he hated Say-Zon
But he loved Ply Knee the Elder!
There is only one success: to be able to spend your life in your own way.

AHA Life Member #33907

#### Pawtucket Patriot

• Senior Brewmaster
• Posts: 1370
• Rebelling against cheap swill since 2005
##### Re: Why Plato?
« Reply #14 on: July 05, 2013, 05:30:24 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
Matt Schwandt | Minneapolis, MN
AHA Member

Partial-Mash Pictorial
All-Grain Pictorial