VIEW ARTICLE    DOI: 10.1094/ASBCJ-51-0051

A Flow-Injection Analyzer for Determining the Bitterness of Wort and Beer. Shuso Sakuma, Choji Kikuchi, Masahiro Kowaka, and Masao Mawatari, Kirin Brewery Co. Ltd., Yokohama, Japan. J. Am. Soc. Brew. Chem. 51:0051, 1993.

A flow-injection analyzer for determining wort and beer bitterness was developed. A degassed beer sample or a diluted, filtered wort sample is injected into a carrier stream of water containing a surfactant, immediately followed by simultaneous addition of 0.6N hydrochloric acid and isooctane. After mixing in a Teflon tube, the organic phase is separated with a Teflon membrane, and the absorbance at 275 nm is determined. Using this automated method, it is possible to determine the bitterness of wort or beer within a range of 0-50 bitterness units (BU). The coefficient of variation was 0.5% for beer and 0.7% for wort. The correlation coefficient between this method and the ASBC method was 1.000. Values obtained with this method and the ASBC method generally vary by less than 0.5 BU.

Keywords: Beer, Bitterness, Flow-injection analysis, Wort