How do you calculate gravity (og/fg/sg) - Home Brew Forums

 Home Brew Forums > How do you calculate gravity (og/fg/sg)

12-17-2010, 01:34 AM   #1
BrewBoy19
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Dec 2010
Grand Rapids, michigan
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So I forgot to take a beginning measurement because I was in a hurry. Also I have been reading a lot of gravities etc..... and one thing I can find is how the points for certain sugars, extracts, grains etc...... are discovered? Is their a chart I can get so I can have an easy refernce point and go from there until I can memorize them? example : I know that their are points for sugars and points for all the things you put into your beer etc...... but I can't seem to find (and maybe I overlooked it) how these "points" are decided. So the main question is this : I made a ginger ale that I have posted about on here in a different thread and I am trying to figure out what the OG should have been so i can have a reasonable guess at the alcohol content when I take the FG. The sugar I used was cane sugar (8lbs); and then 5 gallons of water 7 oz of ginger and 7 lemons and 3 limes.

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12-17-2010, 01:53 AM   #2
Calder
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Mar 2010
Ohio
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Of the items you noted, only the sugar is fermentable. 1 lb of cane sugar has 45 gravity points, so 8 lbs = 360 points. You made 5 gallons, so divide by 5 = 72. Therefore your starting gravity will be around 1.072.

12-17-2010, 02:34 AM   #3
BrewBoy19
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Dec 2010
Grand Rapids, michigan
Posts: 157
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ok thanks, now can you tell me where I can find a chart or something that gives me the gravity point values of sugars/malts?

12-17-2010, 02:48 AM   #4
ajf
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Oct 2005
Long Island
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You could download Beersmith or Promash, and for malts, you could check out http://www.homebrewtalk.com/wiki/index.php/Malts_Chart
Beersmith and Promash disagree slightly, especially when it concerns sugars.
I use 42 ppg (points per lb per gallon) for dextrose, or 46 ppg with table sugar.

I think these are pretty accurate.

-a.
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12-17-2010, 03:22 AM   #5
Calder
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Mar 2010
Ohio
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Dextrose is 36 points per lb. Cane sugar is 45 or 46. I use 45.

A good reference is Papazian, "The Home Brewers Companion".

12-17-2010, 06:40 AM   #6
barrooze

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Jan 2009
Pearland, TX
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Quote:
 Originally Posted by Calder Dextrose is 36 points per lb. Cane sugar is 45 or 46. I use 45. A good reference is Papazian, "The Home Brewers Companion".
Is beet sugar the same as cane sugar? Aren't they both succrose?
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12-17-2010, 07:34 PM   #7
ajf
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Long Island
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Yes, beet and cane sugar are effectively the same.

-a.
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