Varietal Differences in the Proportions of Cohumulone, Adhumulone, and Humulone in Hops. Gail B. Nickerson and Peggy A. Williams, Department of Agricultural Chemistry, and Alfred Haunold, Agricultural Research Service, USDA, Department of Crop Science, Oregon State University, Corvallis 97331. J. Am. Soc. Brew. Chem. 44:0091, 1986.

Hop α-acids are composed of three major analogues: cohumulone, adhumulone, and humulone. The proportion of cohumulone is a varietal characteristic and ranges from 16 to 50% of the α-acids. The standard deviation of the mean cohumulone ratio of 25 hop varieties analyzed for six years is about 2%. Adhumulone ranges from 6 to 15% of the α-acids, but has greater year-to-year varietal variability than cohumulone or humulone ratio. Losses of α-acids during storage are compatible for all analogues; therefore, the cohumulone content is unaffected. Hop varieties used as kettle hops have higher cohumulone ratios than varieties used as aroma hops. The cohumulone ratio is helpful in varietal identification but cannot be used as the only criterion.

Keywords: Adhumulone, Cohumulone, HPLC, Humulone