What is the main purpose of first wort hopping?

First wort hopping primarily serves to enhance bitterness over the boil. This technique involves adding hops to the brew kettle before the wort is brought to a boil, allowing for a more gentle extraction of hop compounds during the heating process. By doing this, the resulting bitterness tends to be smoother and more integrated into the beer compared to hops added later in the boil.

When hops are added first wort, the gentle heating allows for the isomerization of alpha acids to occur more gradually, which can lead to a rounder bitterness profile. This method can also help in balancing the overall flavor of the beer, as a smoother bitterness often works well with various malt profiles.

While first wort hopping can impart some hop aroma and flavor, depending on the type and amount of hops used, its primary benefit is in the contribution of bitterness, distinguishing it from other hopping techniques aimed primarily at enhancing aroma or maximizing flavor extraction. Thus, it efficiently contributes to achieving the desired balance in the final beer.