title: Influence of the brewing process on furfuryl ethyl ether formation during beer aging.
abstract: In beer, the development of a solvent-like stale flavor is associated with the formation of furfuryl ethyl ether. The synthesis rate of this important flavor compound is proportional to the concentration of furfuryl alcohol in beer. This study shows that furfuryl alcohol in beer is mainly formed by Maillard reactions initiated during wort boiling and malt production. A mechanism for its formation from alpha-(1,4)-oligoglucans and amino acids in wort and beer is proposed. During wort boiling, a quadratic relationship was found between the wort extract concentration, on the one hand, and the increase of furfuryl alcohol and furfural, on the other. The reduction of furfural by yeast during fermentation further increases the furfuryl alcohol content. In pale beers, the furfuryl alcohol concentration is essentially determined by the thermal load on wort during brewing operations. In dark beers, a considerable fraction of furfuryl alcohol may, however, come from the dark malts used. These results lead to important practical conclusions concerning the control over furfuryl ethyl ether in beer.
authors.affiliation: Centre for Malting and Brewing Science, Katholieke Universiteit Leuven, Kasteelpark Arenberg 22, B-3001 Heverlee, Belgium. bart.vanderhaegen@agr.kuleuven.ac.be
authors.forename: Bart
authors.initials: B
authors.lastname: Vanderhaegen
authors.forename: Hedwig
authors.initials: H
authors.lastname: Neven
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Verstrepen
authors.forename: Freddy R
authors.initials: FR
authors.lastname: Delvaux
authors.forename: Hubert
authors.initials: H
authors.lastname: Verachtert
authors.forename: Guy
authors.initials: G
authors.lastname: Derdelinckx
mesh_terms: D001515:Beer / Q000032:analysis*; D002523:Edible Grain; D005019:Ethyl Ethers / Q000032:analysis*; D005511:Food Handling / Q000379:methods*; D005663:Furans / Q000032:analysis*; D001467:Hordeum; D006358:Hot Temperature; D015416:Maillard Reaction; D013649:Taste; D013997:Time Factors; D014835:Volatilization
chemical_list: D005019:Ethyl Ethers; D005663:Furans; C493749:furfuryl ethyl ether; C012986:furfuryl alcohol