Originally Posted by PTBYOOJ
How do you estimate an OG based on the ingredients of an extract recipe.
6Lbs of light dry malt extract
1Lbs Dark dry malt extract
2Lbs specialty grain (some kind of light crystal)
The easiest way is to use a program. There are some free ones available. I think I used Qbrew sometime in the past.
How do you do it! You add up all the gravity points of the fermentables, and divide it by the total volume in the fermenter. For your recipe:
1 lb of DME has 45 gravity points (it will make a gravity of 1.045 if dissolved and made up to 1 gallon). Therefore 7 lbs = 315 gravity points.
Steeping crystal will yield about 50% of it's fermentables, so you will get about 16 to 17 points per lb ..... lets say 35 points for 2 lbs.
Total = 315 + 35 = 350.
Divide that by the total volume in your fermenter. If 5 gallons. your OG will be 1.070.
Hope this helps.