What are beta acids known for in relation to bitterness?

Beta acids are known for providing significantly less bitterness compared to alpha acids. Alpha acids are the primary compounds responsible for the bitterness in beer, and they are isomerized during the boiling process when hops are added, giving rise to the typical bitter flavor profile. In contrast, beta acids do not isomerize in the same way and thus do not contribute to bitterness in beer to the same extent.

Beta acids can influence other characteristics in beer, such as aroma and flavor, but they do not have the same impact on bitterness levels. This fundamental difference in the bitterness contribution is why the correct answer focuses on the lesser degree of bitterness associated with beta acids compared to alpha acids.