Micketts, R.J. and Lindsay, R.C.

Abstract
Tenax GC, a polymer based on 2,6 diphenyl p phenylene oxide, has been used to adsorb beer volatiles swept into the column with nitrogen, and the results compared with those obtained with Porapak Q traps. After initial collection of the volatiles the nitrogen stream was continued long enough to drive off water vapour and ethanol and the trap was then heated and the volatiles backflushed into traps immersed in liquid nitrogen. The traps were then connected to the inlet of a gas chromatograph for identification of the volatiles. No bleed peaks were observed when the Texax GC trap was used in contrast to a large number of bleed peaks when the Porapak Q trap was used. Tenax GC gives better relolution than Porapak Q and the profiles from the former were very reproducible.
Keywords: absoreption analysis beer concentration flavour gas chromatography polymer volatile compound