Aroma Properties of Lager Beer Dry-Hopped with Oxidized Hops

Daniel M. Vollmer, Victor Algazzali, and Thomas H. Shellhammer (1), Department of Food Science & Technology, Oregon State University, 100 Wiegand Hall, Corvallis, OR 97331, U.S.A. J. Am. Soc. Brew. Chem. 75(1):22-26, 2017.

(1) Corresponding author. Phone: +1.541.737.9308. E-mail:

​We observed qualitative changes in the chemical and aroma profile of Hallertau Mittelfrüh (HA) hop pellets after storage under prooxidative conditions. It was hypothesized that lager beer dry-hopped with oxidized HA hops would impact both the qualitative attributes related to “noble” hop aroma in the finished beer and consumer acceptance. Lager beer was dry-hopped using both properly stored and oxidized hops at two different hopping rates (3.8 and 1.5 g/L). Trained panelists using descriptive analysis evaluated the beer dry-hopped at 3.8 g/L. At this dosing rate, significant qualitative changes were observed in the beer as a result of using oxidized hops, showing differences in the attributes woody and herbal, which are associated with noble hop aroma. Sixty consumers rated their acceptance of the beers dry-hopped at a lower rate of 1.5 g/L, and no significant difference in overall liking was found between the hop preparations. Although changes in hop oil chemistry occur as a result of oxidation, these changes may not adversely affect overall liking of beer prepared with oxidized hops, but may serve as a way to enhance noble hop aroma in lager beer. Keywords: Dry hopping, Hallertau Mittelfrüh, Consumer acceptance, Oxidation