Gravity Question - Adding sugar after fermentation has begun

[BrewclearAssault]

I snagged Sam Calagione's Extreme Brewing from the library and I'm currently brewing my second (modified) recipe from his book. First, I did the Imperial Pale Ale recipe, and now I'm doing a weizen- my only question is about gravity calculation.

In the imperial pale ale, he says to add brown sugar after a couple days of fermenting- since this obviously adds more sugar to the brew it should raise the gravity. My question is- by how much, or is there a way to accurately get a reading?

I'm also doing a Weizen where i'll be adding fruit in the secondary, but again the fruit is going to add more sugars after its started fermentation, so same question to that

For the record, i'm not too worried about it- the imperial is finished and turned out great, best beer I've ever made! I'd just like to get accurate gravity readings for the records

 

[TopherM]

1 lb of brown sugar adds .046 gravity to 1 gallon of water, so it'll add 0.0092 gravity points to a 5 gallon batch. Just simple division math if you have a different sized batch or if you are boiling and dissolving the brown sugar in XX gallons of water before you add it to the existing solution.

Hope that helps!

 

[BrewclearAssault]

It sure does, thanks man