Originally Posted by histo320
I meant to say adding to the wort, not mash. My mistake.
I saw a recipe for for Zombiedust that called for a First Wart Hop and the IBU was only about 18.1 with Citra. I put it in on Beersmith and it gave me a ridiculous IBU which would be way to bitter for any human to drink.
I just put in .75 oz of Citra at 60, I figure that would basically be the same as a first wort hop.
No, FWH goes into the wort during the first runnings and "steeps" until the wort is brought to a boil. It still gives the IBUs of the longer boil, but since the hops steep before the boil in the hot (150-170 degree) wort, it gives a smoother bitterness and not harsh. Some people calculate the IBUs of FWH as a 20 minute addition, but I feel that it still provides a typical amount of bitterness but in a less harsh way.
Adding hops at 60 minutes does provide bitterness, but it's not the same at all as FWH.
Try it yourself! Make one batch with tradition 60 minute hops and one with appropriate FWH. Then see if you like the differences.