Investigation into the use of carbon isotope ratios (13C/12C) of Scotch whisky congeners to establish brand authenticity using gas chromatography-combustion-isotope ratio mass spectrometry

Abstract Volatile congeners of whisky have been analysed by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Acetaldehyde, ethyl acetate, n -propanol, isobutanol and amyl alcohol from a popular blended whisky have been separated using established GC conditions and their δ 13 C%. values determined. Eight samples of the whisky blend taken over the last 2 years of production have been analysed to allow the authentic range to be determined. A radar diagram has been used to graphically represent the δ 13 C%. data. This was used as a simple means of comparing the carbon isotope profiles of whiskies. Two other whisky samples were analysed and shown to differ from the whisky blend on the basis of the δ 13 C values.