VIEW ARTICLE    DOI: 10.1094/ASBCJ-45-0023

Determination of Low Molecular Weight Organic Compounds in Beer Using Capillary Gas Chromatography. D. B. Hawthorne, T. E. Kavanagh, and B. J. Clarke, Carlton and United Breweries Limited, Melbourne, Australia. J. Am. Soc. Brew. Chem. 45:0023, 1987.

A simple, rapid procedure for the extraction of trace organic volatile components from beer was developed. The procedure involves adsorption of the components onto XAD-2 resin followed by desorption with diethyl ether and analysis of the extract by capillary gas chromatography. Relative recoveries of most of the common esters, higher alcohols, and fatty acids found in beer are 95% or better, whereas the absolute recoveries for most substances are above 50%. The repeatability of the method has a coefficient of variation of 6% or better, and the long-term repeatability and reproducibility coefficients of variation for most substances lie in the range 3-12%. The method is equally good for packaged beers, end-of-fermentation beers (after yeast removal) and storage beers. It is suitable for batchwise preparation of samples and, with automatic injection on a single chromatograph, up to 70 beer samples per week can be analyzed in duplicate. Besides the major components, several minor compounds in beer can also be determined, including furfural at concentrations that enable furfural to be used as a marker compound for heat stress. Furfural formation and heat stress in beer were found to be correlated.

Keywords: Beer analysis, Esters, Fatty acids, Flavor, Furfural, Higher alcohols