Analysis of hop acids by capillary electrophoresis

Micellar electrokinetic. chromatography (MEKC) was used to separate compone nts of hop extracts. The separation of a sample of iso-alpha -acids by MEKC was better and faster than by an established HPLC method, giving < 0.8 % R SD on migration times and 5-10% RSD on peak areas. MEKC was also successful ly used to separate the oxidation products of the <alpha>- and beta -acids and thus to monitor the stability of hop products containing them. Furtherm ore, MEKC distinguished among samples of reduced iso-alpha -acids (rho-, te trahydro- and hexahydro- derivatives). (C) 2001 Elsevier Science Ltd. All r ights reserved.