### Author Topic: Whats my OG?  (Read 2328 times)

#### amh0001

• Cellarman
• Posts: 84
##### Whats my OG?
« on: June 25, 2013, 10:49:10 PM »
Hello all!

I brewed Tasty's Session Pale ale today. I ended up getting a OG for 1.040 instead of 1.044, so I added some DME.

I had approximately 2.75 gallons of 1.040, and i made 1200 ML of 1.100 wort and added it. What would that bring my OG to? And what is the math to figure this out?

Thanks a ton!

#### yso191

• Senior Brewmaster
• Posts: 1784
• Yakima, WA
##### Re: Whats my OG?
« Reply #1 on: June 25, 2013, 11:23:54 PM »
Why not just test it again?
Steve
All Hands Brewing
BJCP #D1667

#### amh0001

• Cellarman
• Posts: 84
##### Re: Whats my OG?
« Reply #2 on: June 25, 2013, 11:32:26 PM »
Well im actually going to, but i was curious of the math?

#### duboman

• Senior Brewmaster
• Posts: 1576
##### Whats my OG?
« Reply #3 on: June 25, 2013, 11:57:04 PM »
One lb of DME. Will yield ~45 gravity points per gallon

So 45/2.75g=~16 gravity points or 1.016

I think I did that right....?
Peace....Love......Beer......

The Commune Brewing Company-Perfecting the craft of beer since 2010

#### amh0001

• Cellarman
• Posts: 84
##### Re: Whats my OG?
« Reply #4 on: June 26, 2013, 12:18:08 AM »
hmm i took a sample and it seems, i only got 1 gravity point =(

#### duboman

• Senior Brewmaster
• Posts: 1576
##### Whats my OG?
« Reply #5 on: June 26, 2013, 12:36:31 AM »

hmm i took a sample and it seems, i only got 1 gravity point =(

I'm no math major but google tells me there are 3785ml in a gallon and you added 1200ml into 2.75 gallons so that's about 1/4 of your 1.10 wort which if I'm estimating this all correctly would equate to your 1 gravity point

Sorry, I'm definitely not a master of these calculations.....perhaps someone more experienced can chime in:)
Peace....Love......Beer......

The Commune Brewing Company-Perfecting the craft of beer since 2010

#### Hokerer

• I spend way too much time on the AHA forum
• Posts: 2645
• Manassas, VA
##### Re: Whats my OG?
« Reply #6 on: June 26, 2013, 12:50:46 AM »
I had approximately 2.75 gallons of 1.040, and i made 1200 ML of 1.100 wort and added it. What would that bring my OG to? And what is the math to figure this out?

First, you need to straighten out your units.  So 1200 ml converts to about 40.5 ounces which is about .316 gallons...

Figure "points" by multiplying the volume by the gravity (without the 1. part)...

2.75 gallons times 40 gives you 110 "points";  .316 gallons time 100 gives you 31.6 "points"; so you've got a total of 141.6 "points".

Divide that by 3.066 gallons (2.75 & .316) and you should end up with a gravity of about 1.046
Joe

#### HoosierBrew

• Global Moderator
• I must live here
• Posts: 13030
• Indianapolis,IN
##### Re: Whats my OG?
« Reply #7 on: June 26, 2013, 12:54:12 AM »

hmm i took a sample and it seems, i only got 1 gravity point =(

I'm no math major but google tells me there are 3785ml in a gallon and you added 1200ml into 2.75 gallons so that's about 1/4 of your 1.10 wort which if I'm estimating this all correctly would equate to your 1 gravity point

Sorry, I'm definitely not a master of these calculations.....perhaps someone more experienced can chime in:)
Since a lb of DME gets ~ 45 points/lb/gallon, if you take the 45 points and divide by 5 (for a 5 gallon batch or whatever number for your batch size), you get 9 points for the lb in a 5 gallon batch.  Then divide the number of points you want to increase your gravity by 9 to get the lbs of DME to use.
Jon H.

#### duboman

• Senior Brewmaster
• Posts: 1576
##### Whats my OG?
« Reply #8 on: June 26, 2013, 12:59:05 AM »

hmm i took a sample and it seems, i only got 1 gravity point =(

I'm no math major but google tells me there are 3785ml in a gallon and you added 1200ml into 2.75 gallons so that's about 1/4 of your 1.10 wort which if I'm estimating this all correctly would equate to your 1 gravity point

Sorry, I'm definitely not a master of these calculations.....perhaps someone more experienced can chime in:)
Since a lb of DME gets ~ 45 points/lb/gallon, if you take the 45 points and divide by 5 (for a 5 gallon batch or whatever number for your batch size), you get 9 points for the lb in a 5 gallon batch.  Then divide the number of points you want to increase your gravity by 9 to get the lbs of DME to use.

This I knew but the conversions with gallons and ml were throwing my feeble math mind.

Thanks hokerer for the math lesson!
Peace....Love......Beer......

The Commune Brewing Company-Perfecting the craft of beer since 2010

#### amh0001

• Cellarman
• Posts: 84
##### Re: Whats my OG?
« Reply #9 on: June 26, 2013, 01:00:52 AM »
Thank you for the input guys, there definitely is a lot to it. i wonder if my reading wasn't mixed well enough only showing me .01 in gravity raise.

#### HoosierBrew

• Global Moderator
• I must live here
• Posts: 13030
• Indianapolis,IN
##### Re: Whats my OG?
« Reply #10 on: June 26, 2013, 01:04:05 AM »

hmm i took a sample and it seems, i only got 1 gravity point =(

I'm no math major but google tells me there are 3785ml in a gallon and you added 1200ml into 2.75 gallons so that's about 1/4 of your 1.10 wort which if I'm estimating this all correctly would equate to your 1 gravity point

Sorry, I'm definitely not a master of these calculations.....perhaps someone more experienced can chime in:)
Since a lb of DME gets ~ 45 points/lb/gallon, if you take the 45 points and divide by 5 (for a 5 gallon batch or whatever number for your batch size), you get 9 points for the lb in a 5 gallon batch.  Then divide the number of points you want to increase your gravity by 9 to get the lbs of DME to use.

This I knew but the conversions with gallons and ml were throwing my feeble math mind.

Thanks hokerer for the math lesson!
Figured you did , dude.  Just put it out there for amh001, in case.  Those ml conversions are a little trickier though.
Jon H.

#### klickitat jim

• I must live here
• Posts: 8460
##### Re: Whats my OG?
« Reply #11 on: June 26, 2013, 01:28:51 AM »
OWell let's see, there's about 5 ml in a teaspoon. ..

The problem is mixing patriot measuring with metric. Too much thinkin involved.

Divided by gallons of high quality h2O
Cane sugar is 46 pts lb
DME is 45 pts lb
LME is 36 pts lb

1 lb DME per 2.5 gal = 18 pts

You can do it backwards too.
2.5 gallons of 1.060 becomes what when you add 2.5 gallons of h2O,
2.5 x 60 = 150 total pts
150 divided by 5 = 30 or 1.030
« Last Edit: June 26, 2013, 01:34:03 AM by klickitat jim »

#### yso191

• Senior Brewmaster
• Posts: 1784
• Yakima, WA
##### Re: Whats my OG?
« Reply #12 on: June 26, 2013, 02:41:54 AM »
Well im actually going to, but i was curious of the math?

Oh!  I don't do any math I don't have to, so naturally I didn't tumble to the idea that you wanted to just for the 'joy of math.'  In my world 'joy of math' is an oxymoron.
Steve
All Hands Brewing
BJCP #D1667

#### Joe Sr.

• Official Poobah of No Life.
• Posts: 4345
• Chicago - NORTH SIDE
##### Re: Whats my OG?
« Reply #13 on: June 26, 2013, 02:09:32 PM »
i wonder if my reading wasn't mixed well enough only showing me .01 in gravity raise.

Most likely.  Wort will stratify particularly when you are topping off or adding additional wort as you did.

If the reading seems off, mix well and check again.  I get crazy high readings if I haven't mixed my top off water into the wort very well.
It's all in the reflexes. - Jack Burton