Comprehensive Structural Analysis of the Bitter Components in Beer by the HPLC‐Assisted Crystalline Sponge Method

Trans‐iso‐α‐acid is one of the main contributors to the bitter taste of fresh beer and is known to transform into various derivatives during beer aging. However, structural characterization of the derivatives has been a challenging task because of the formation of too many components. Herein, we report that most of the transformation products of trans‐iso‐α‐acid, isolated in this study in only small quantities by HPLC, can be structurally analyzed with the crystalline sponge method. Thirteen compounds, including eight that were previously unreported, have been successfully isolated and analyzed with complete assignment of their absolute configuration. This provides an improved understanding of the chemical transformations that occur during beer aging. Beer taste of your favorite is blendable! Comprehensive identification of derivatives from trans‐iso‐α‐acid, derived from one of the most abundant secondary metabolites in hops, was achieved by the HPLC‐assisted crystalline sponge method. Thirteen components, including previously unknown eight, were fully characterized, promising the development of new, advanced brewing technology for controlling the bitter components of beer.