Author Topic: Adjusting gravity with DME  (Read 29001 times)

Offline ImperialStout

  • BeerSmith Brewer
  • ***
  • Posts: 31
  • BeerSmith 2 Rocks!
Adjusting gravity with DME
« on: January 18, 2013, 03:12:56 PM »
Just learned SG and OG can be increased by adding DME. Anyone know about how much DME to add per gravity point? Are we talking spoonfuls or cupfuls of DME for a 5 gal batch?

Trial and error works, just thought someone already knows.

Offline tom_hampton

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 929
  • BeerSmith 2 Rocks!
    • Tom's Miata Racing Blog
Re: Adjusting gravity with DME
« Reply #1 on: January 18, 2013, 03:58:09 PM »
The answer depends on your volume. In order to understand how to do this you need to understand how total points works. To calculate total points in wort: 1000*(gravity - 1)*volume.  Basically, just keep everything on the right side of the decimal point * volume.  Also, for hot wort, you need to correct for temperature (3-4%).   This gives you a number that represents the total amount of sugar in the wort.

So, what you do is calculate the desired total sugar using your recipe data, then calculate your actual sugar. SubtrCt your actual from desired. That tells you how many points you need to add. Dme adds 46 points per pound.

For example:

Target preboil sg: 1.052
Target volume:  7.5 gallons
Target points: 52 * 7.5 =390 pts

Actual sg: 1.049
Actual volume: 7.6 gallons
Actual points: 372 pts

Needed pts: 390-372 = 18 pts
Needed dme: 18/46 =6.2 ounces



R.I.P.:Belgian Blonde
On Tap: Apfelwein, Kolsch(v2), Pumpkin Ale, Belgian Specialty 
Aging/Storing: Coffee Porter, Chocolate Porter, Flanders Red, English Barlywine
Fermenting: Maggie's Altbier
Next Up: PtE(1.1), Belgian Dubbel?

Working thru all BCS recipes

Offline GoodisBeer

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 106
    • Flannel Shirt Brewing
Re: Adjusting gravity with DME
« Reply #2 on: January 18, 2013, 04:35:07 PM »
We brew AG because we like understanding the process. Thanks Tom, it makes sense. Also, BS has a simple tool to use as well. Can't remember where it is, possibly tools/calculators...

Offline ImperialStout

  • BeerSmith Brewer
  • ***
  • Posts: 31
  • BeerSmith 2 Rocks!
Re: Adjusting gravity with DME
« Reply #3 on: January 18, 2013, 04:46:18 PM »
Thanks. Will save the post and do the math if (when) I need to adjust the gravity. Brew Smith is still the best brewing software but could be tweaked. Rev 3 coming out anytime soon?

Offline ImperialStout

  • BeerSmith Brewer
  • ***
  • Posts: 31
  • BeerSmith 2 Rocks!
Re: Adjusting gravity with DME
« Reply #4 on: January 19, 2013, 11:46:45 AM »
I posted this same question on two other beer web sites. Several people replied 1 pound of DME will raise the gravity by 9 points in a 5 gal batch.

After thinking about this more carefully, I am thinking 9 points is a good number.

If 46 were correct wouldn't that mean a gravity of 1.092 could be achieved with only two pounds of DME in a 5 gal batch.

If 9 is correct, that would mean it would take 10 pounds of DME to get a gravity reading of 1.090.

I am thinking 9 is a good number. Any thoughts?




« Last Edit: January 19, 2013, 12:01:36 PM by ImperialStout »

Offline Rusty Nails

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 141
Re: Adjusting gravity with DME
« Reply #5 on: January 19, 2013, 05:53:24 PM »
Please see Tom's example above.
In this case;
92 (points wanted) * 5 (gallons) = 460 (total points needed)
460 (total points needed) / 46 (points in 1# DME) = 10# DME

Offline ihikeut

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 199
  • BeerSmith 2 Rocks!
Re: Adjusting gravity with DME
« Reply #6 on: January 19, 2013, 07:06:17 PM »
I don't do much extract brewing but I think it's just a misunderstanding of the equation.

1# DME in 1 gal of water = 46 points (1.046)
1# DME in 5 gal of water =  9.2 points (1.0092)

Offline ImperialStout

  • BeerSmith Brewer
  • ***
  • Posts: 31
  • BeerSmith 2 Rocks!
Re: Adjusting gravity with DME
« Reply #7 on: January 19, 2013, 07:39:52 PM »
Thank you very much. Those decimal points do make a difference.

 

modification