Abstract
An automated method based on on-line sample enrichment by precolumn switching has been developed for the determination of hop bittering components in beer and wort. A combination of two columns was used: a tetramethylolmethanetriacrylate type for trapping and an ODS silica type for final separation. Iso-α-acids and α- acids were determined with similar results by the conventional method, based on off-line sample enrichment (liquid- liquid extraction and concentration). The analysis was carried out with good reproducibilities (rsd less than 3%). Precolumn switching is distinguished by injection of beer and wort samples without preteatment, and is eminently suited for automated routine analysis in breweries.
