Phillip Liescheski (1); (1) Teledyne Isco, Lincoln, NE, U.S.A.

Analytical
Poster

The alpha- and beta-acid profiles of hops and beer characterize their flavor and antibacterial properties, which are important in brewing and storing beers and ales. Hops have been assayed by organic liquid solvent extraction and followed by conventional reverse-phase HPLC. Recently, subcritical and supercritical carbon dioxide (i.e., supercritical fluid extraction [SFE]) has been used as an extracting solvent. In this poster, we explore the use on hops of SFE with carbon dioxide and flash LC—a faster and simpler low-pressure liquid chromatography method. Neat beer samples are extracted by SFE after fixing onto calcined diatomaceous earth. We will also explore the use of ultra-high–pressure liquid chromatography (UHPLC) in the final analysis.

Phillip B. Liescheski received a B.A. degree in chemistry and mathematics from the University of St. Thomas in Houston, TX. He continued his education at the University of Texas in Austin, earning a Ph.D. degree in chemical physics. With a NATO fellowship, he worked on liquid crystal NMR at Edinburgh University in Scotland. He has been employed at Teledyne Isco in Lincoln, NE, as a research scientist since 1989. He has published several articles in scientific journals and U.S. patents in SFE. His wife, Joan, enjoys his home-brewed ales and meads.