Happy HolidaySs Giveaway - Winners Re-Re-Drawn - 24 hours to Claim!

Get your HBT Growlers, Shirts and Membership before the Rush!

 Home Brew Forums > Starting gravity calculation?
04-30-2008, 06:59 PM   #1
endlesssurf
Feedback Score: 0 reviews
Recipes

Join Date: Mar 2008
Location: Richmond
Posts: 38
 Starting gravity calculation?

just out of curiosity how do u calculate starting gravity with out taking a hydrometer reading?

__________________

04-30-2008, 07:01 PM   #2
homebrewer_99
Feedback Score: 0 reviews

Recipes

Join Date: Feb 2005
Location: Atkinson (near the Quad Cities), IL
Posts: 17,951
Liked 88 Times on 77 Posts
Likes Given: 1

I think DME is rated like .8% per pound, but you really have to know the volume of water also.

__________________
HB Bill

04-30-2008, 07:21 PM   #3
TexLaw
Here's Lookin' Atcha!
Feedback Score: 0 reviews

Recipes

Join Date: Sep 2007
Location: Houston, Texas
Posts: 3,698
Liked 25 Times on 24 Posts

Grains and extracts have an "extract potential," which is the resulting gravity if you added one pound of the extract (or specialty grain) in question to a gallon of water or mashed one pound of the base grain into a gallon of water at 100% efficiency. You take that extract potential number and do a little algebra.

TL

__________________
Beer is good for anything from hot dogs to heartache.

Drinking Frog Brewery, est. 1993

05-01-2008, 05:00 AM   #4
Got Trub?
Feedback Score: 0 reviews
Recipes

Join Date: Apr 2007
Location: Washington State
Posts: 1,538
Liked 7 Times on 5 Posts

You could also use brewing software.

GT

__________________

05-01-2008, 05:28 AM   #5
Brett0424
Feedback Score: 0 reviews
Recipes

Join Date: Jan 2008
Location: dallas, tx
Posts: 266
Liked 1 Times on 1 Posts

Extract or grains?
Multiply the number of gravity points per pound per gallon by how many pounds you are using and divide by them number of gallons you are making.

Example:
6 pounds LME (at 34 gravity points per pound per gallon)x6lbs=204 gravity points.
204/5 gallons=40.8
So with 6 pounds of LME you will have about a 1.041 beer.

If using grains you need to know your efficiency. Say the grains have a potential of 37 gravity points per pound per gallon and your efficiency is 70%.
6 pounds grainx37(gravity points per pound per gallon)x0.7(efficiency)=155.4
155.4/5 gallons=31.08 or a SG of about 1.031.

__________________

05-01-2008, 12:15 PM   #6
carl spakler
Registered User
Feedback Score: 0 reviews
Recipes

Join Date: Apr 2008
Location: MA
Posts: 294
Liked 1 Times on 1 Posts

http://beertools.com/html/calculator.php

Free and easy.
__________________