S.G. Yield

hopsalot · 09-23-2008, 04:39 PM

Can some one point me to a thread or a link with information concerning:

S.G. Yield, I am trying to calculate what my SG would be...

**david_42** · 09-23-2008, 04:58 PM

The Beer Recipator 2.2

hopsalot · 09-23-2008, 05:02 PM

I have used the recipator before, works great but I wanted to be able to calculate on paper. Am i out of line thinking I can do this?

**mmb** · 09-23-2008, 05:40 PM

SG = (W * PPG * EE)/ V

OG in points = (lbs of malt used) * (points per pound per gallon)* (expected extract efficiency) / (gallons of beer brewed)

The ppg score is the number that you see quoted in the fine print on your extracts or grains. You can use the values on the Beer Recipator for general data.

This gives you the gravity in "gravity points" example 48 points = 1.048

hopsalot · 09-23-2008, 06:46 PM

Thx mmb that is what I was looking for, when dealing with multiple grains do you have to take a weighted sum of PPG in order to calculate the O.G, for example:

Malt % PPG

Pale malt = 86% 37 ppg
Munich = 7% 33 ppg
Crystal 60L = 6% 34 ppg

Total PPG = (.86)*(37) + (.07)*(33) + (.06)*(37) = 36.35

O.G. = (12.75 lbs)*(36.35)*(.75) / 5.5 gal = 63.199

O.G. = 1.063

Checked out on recipator, is a weighted sum the best way to calculate O.G. by hand?

**mmb** · 09-23-2008, 08:32 PM

I've only done it with the weights of the malts used and then summed the points. Your fancy new math is blowing my mind.

hopsalot · 09-23-2008, 11:42 PM

thank you, I guess all this college is paying off... maybe. your post made me think about it so you are to blame somehow.

Cheers