Simultaneous determination of E-2-nonenal and beta-damascenone in beer by reversed-phase liquid chromatography with UV detection.
A method for the simultaneous determination of E-2-nonenal and beta-damascenone in beer by reversed-phase liquid chromatography using UV detection is presented. The method consists of beer steam distillation, followed by an extraction/concentration step using Sep-Pak Plus C18 RP cartridges and determination by HPLC at 226 nm UV-absorption maximum. The identity of the compounds was confirmed by GC analysis with MS detection of the isolated fractions. A recovery factor of approximately 80% was obtained for beta-damascenone with a R.S.D. of 3%. E-2-Nonenal and beta-damascenone were monitored in a comparative study of fresh and either naturally and forced aged beer. The results obtained show that both compounds have a similar behaviour through an extended storage of beer and consequently can be used as good analytical markers of beer ageing. Nevertheless, the use of beta-damascenone seems to be more convenient because this compound appears in beer in higher concentrations than E-2-nonenal, thus making it easier to measure.
Guido
L F
LF
Departamento de Química, Faculdade de Ciências, Centro de Investigação em Química da Universidade do Porto, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
Carneiro
J R
JR
Santos
J R
JR
Almeida
P J
PJ
Rodrigues
J A
JA
Barros
A A
AA
D000447:Aldehydes / Q000032:analysis*; D001515:Beer / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D045792:Norisoprenoids / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*
D000447:Aldehydes; D045792:Norisoprenoids; C013166:2-nonenal; C075388:beta-damascenone