Journal of the american society of brewing chemists vol:60 issue:2 pages:88-96
A quantitative assay of beer aromatic alcohols was developed using gas chromatography (GC) in conjunction with stable isotope dilution analysis (SIDA). Quantification using SIDA is not subject to instrumental and/or sample manipulation variation as any analytical variation has a similar effect on the aromatic alcohols and their corresponding labeled analogs used as internal standard. A range of beers (lager and ale) was spiked with known amounts of deuterated aromatic alcohols, followed by extraction using ethyl acetate. The beer aromatic alcohols were quantified by GC-mass spectrometry using the corresponding deuterated aromatic alcohols as internal standards. The method was found to be highly repeatable and accurate for the quantification of aromatic alcohols in beer and was far less time-consuming than the conventional method. The aromatic alcohol data for various commercial lagers and ales was statistically analyzed using discriminant function analysis. With few exceptions, the results demonstrated that lagers and ales cannot be distinguished on the basis of the level of aromatic alcohols they contain.