VIEW ARTICLE    DOI: 10.1094/ASBCJ-43-0136

Simultaneous Analysis of Hop Bittering Components by High-Performance Liquid Chromatography and Its Application to the Practical Brewing. M. Ono, Y. Kakudo, Y. Yamamoto, K. Nagami, and J. Kumada, Central Research Institute of Suntory Ltd., Osaka 618, Japan. J. Am. Soc. Brew. Chem. 43:0136, 1985.

Simultaneous analysis for α-, β-, and iso-α-acids has been improved to allow the complete determination of nine major hop bittering components with a single assay method in less than 30 min. The improvements for separation of each analog of both α- and β-acids were as follows: a pH gradient (pH 3.0-5.3) with ion pairing was used based on the pK of their individual analogs, and the detection wavelength of 302 nm was chosen, as the absorbance for each analog does not change between pH 2.7 and pH 7.2 (isosbestic point). These improvements progressively increased both resolution and precision. The method is sufficiently simple, rapid, and reproducible for routine analysis in the brewery. This method has been successfully applied to the control of the hop bittering components during the brewing process from hops to finished beer.

Keywords: α-Acids, β-Acids, Beer, Hops, Hop extracts, Iso-α-acids, ?-Isohumulones, Simultaneous analysis method