title: New Insight into the Role of Sucrose in the Generation of α-Diketones upon Coffee Roasting.
abstract: The origin and formation pathways of the buttery-smelling α-diketones 2,3-butanedione and 2,3-pentanedione upon coffee roasting were studied by means of biomimetic in-bean experiments combined with labeling experiments. For this purpose natural sucrose in the coffee bean was replaced by fully or partially13C-labeled sucrose or by a mixture of unlabeled and fully13C-labeled sucrose (CAMOLA approach). The obtained data point out that sucrose contributes to both α-diketones; however, its importance and reaction pathways clearly differ. Whereas the major part of 2,3-pentanedione originates from sucrose (about 76%), its contribution to 2,3-butanedione is much lower (about 35%). Formation from intact sugar skeleton is the major pathway generating 2,3-pentanedione from sucrose, whereas 2,3-butanedione is mainly generated by recombination of sucrose fragments. The contribution of glucose and fructose moieties of sucrose to both α-diketones is comparable. Finally, kinetic experiments with fully labeled sucrose showed that the contribution of sucrose changes during roasting.
authors.affiliation: Nestlé Product Technology Centre Orbe, Nestec Ltd. , CH-1350 Orbe , Switzerland.
authors.forename: Luigi
authors.initials: L
authors.lastname: Poisson
authors.affiliation: Nestlé Product Technology Centre Orbe, Nestec Ltd. , CH-1350 Orbe , Switzerland.
authors.forename: Noémie
authors.initials: N
authors.lastname: Auzanneau
authors.affiliation: Nestlé Product Technology Centre Orbe, Nestec Ltd. , CH-1350 Orbe , Switzerland.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Mestdagh
authors.affiliation: Nestlé Research Centre , P.O. Box 44, CH-1000 Lausanne 26 , Switzerland.
authors.forename: Imre
authors.initials: I
authors.lastname: Blank
authors.affiliation: Nestlé Product Technology Centre Orbe, Nestec Ltd. , CH-1350 Orbe , Switzerland.
authors.forename: Tomas
authors.identifier: http://orcid.org/0000-0002-4555-8492
authors.initials: T
authors.lastname: Davidek
mesh_terms: D040503:Coffea / Q000737:chemistry*; D003296:Cooking; D006358:Hot Temperature; D007659:Ketones / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry*; D013395:Sucrose / Q000737:chemistry*
chemical_list: D007659:Ketones; D013395:Sucrose
keywords: CAMOLA; coffee; flavor; precursor; roasting; sucrose