High-Performance Liquid Chromatography Analysis of Tetrahydro-Iso-α-Acids in Beer

Abstract

An improved method for the measurement of tetrahydro-iso-α-acids and iso-α-acids in beer is presented. The method is based upon the HPLC separation of hop acids on a C8 reverse-phase column using gradient elution with a citrate buffer at a pH of 7.0. The method is suitable for measurement of small additions of tetrahydro-iso-α-acids for foam improvement as well as for the determination of trace amounts of iso-α-acids in a beer designed to be light stable.