VIEW ARTICLE    DOI: 10.1094/ASBCJ-53-0009

Liberty and Crystal—Two New U.S.-Developed Aroma Hops (1,2). Alfred Haunold, USDA-ARS, Department of Crop and Soil Science, Gail B. Nickerson, Department of Agricultural Chemistry, Ulrich Gampert, Department of Crop and Soil Science, and Donna Kling, Department of Agricultural Chemistry, Oregon State University, Corvallis, OR; and Stephen T. Kenny, Washington State University, Prosser, WA. (1) Presented in part at the 59th Annual ASBC Meeting, Tucson, AZ, June 1993. (2) Contribution of the USDA, Agricultural Research Service, in cooperation with the Oregon, Washington, and Idaho Agricultural Experiment Stations. Technical paper 10465. J. Am. Soc. Brew. Chem. 53(1):9-13, 1995. Accepted June 9, 1994. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. American Society of Brewing Chemists, Inc., 1995.

Liberty and Crystal, two triploid female half-sister selections with largely German Hallertauer mittelfrüh ancestry were found to be suitable for commercial production in hop growing areas in Washington and Oregon but not in southern Idaho. Their yield potential is substantially higher than that of Hallertauer mittelfrüh and other European aroma hops currently being imported into the United States. Liberty's soft resin and essential oil content are similar to that of Hallertauer mittelfrüh, while Crystal's soft resin composition more closely resembles that of the Czech aroma hop Saazer. In contrast to Saazer, however, Crystal contains no farnesene in its essential oil. Production of Liberty has increased moderately in Washington and Oregon since its public release, primarily to replace certain imported aroma hops. Crystal, released in 1993, is of particular interest to small brewers for production of highly aromatic specialty beers. Keywords: Essential oil, European type, Flavor, Quality, Soft resins, Yield