Originally Posted by logan3825
As you probably know, hops add 3 things to your beer. Bitterness, flavor and aroma. They add more bitterness and less aroma/flavor the longer you boil them. Hop bursting is boiling for a shorter time so you don't boil off as much aroma and flavor. You still add bitterness but not as much so you have to add more hops. You do something like a 20m boil and hop the crap out of it to get a decent amount of bitterness but since the boil is so short you don't boil off much aroma or flavor.
Exactly, bitterness is achieved by boiling longer because the AA are not water soluble and take longer to undergo isomerization. You do get bittering from later additions, but they impact at a lower ratio. Using Beersmith, I calculated the IBU impact of 1oz of centennial pellets at 60, 20, and 5 minutes on 8 lbs of LME. Results as follows:
60 minute - 23.9 IBU
20 minute - 14.5 IBU
5 minute - 4.8 IBU
According to traditional wisdom, the 60 minute addition is for bittering, 20(ish) for flavor, and 5(ish) for aroma. So if you are going to try and achieve normal levels of bittering through hop bursting you are going to have big flavor and aroma (something I like).
To the OP, good luck with your experimenting and, as always, come back and share the results!