Which of the following is NOT one of the American hop varieties?

The variety that is not an American hop is Hallertau. Hallertau is actually a traditional hop variety from Germany, specifically from the Hallertau region, which is one of the oldest and most renowned hop-growing areas in the world. It is famous for its mild and balanced aroma, commonly used in traditional lager beer styles, particularly in German brewing.

In contrast, the other options—Cascade, Chinook, and Mosaic—are all distinctly American hop varieties. Cascade, developed in Oregon, is notable for its floral and citrus qualities and is a flagship hop in many American Pale Ales. Chinook is known for its spicy and pine characteristics, contributing to a wide range of American ales. Mosaic, a more modern variety, is recognized for its complex aroma profile that includes tropical fruit and earthy notes, making it popular in various beer styles, especially craft beers. Each of these American hops brings unique flavors and aromas that are distinct in the craft brewing landscape.