Flavour impact of aged beers

Using a gas chromatography olfactometry (GCO) technique, it has been possib le to identify a number of flavour impact components of fresh, naturally ag ed and forced aged lager One of the benefits of this technique is that a wi de range of volatile flavour components, for example esters, aldehydes, sul phur compounds and lactones can be examined within a single analysis. Toget her with appropriate conventional chemical analysis for aldehydes and senso ry analysis, it has also been possible to relate perceived changes in overa ll flavour balance to some specific changes in aldehyde levels during agein g. In this way, time dependent changes in the levels-of-methional, phenylac etaldehyde, 4-methoxybenzaldehyde, octanal, (E)-2-nonenal have been indicat ed. GCO allows for the convenient detection of flavour components whose contrib ution may remain undetected by current conventional chemical analysis but w hich may play a key role in determining the flavour impact of aged beers.