title: Chemical characterization and antioxidant properties of coffee melanoidins.
abstract: Melanoidins, the brown polymers formed through Maillard reaction during coffee roasting, constitute up to 25% of the coffee beverages' dry matter. In this study chemical characterization of melanoidins obtained from light-, medium-, and dark-roasted coffee beans, manufactured from the same starting material, was performed. Melanoidins were separated by gel filtration chromatography and studied by MALDI-TOF mass spectrometry. Results showed that the amount of melanoidins present in the brews increased as the intensity of the thermal treatment increased, while their molecular weight decreased. The antioxidant activity of melanoidins isolated from the different brews was studied by using different methodologies. Melanoidins antiradical activity determined by ABTS(*)(+) and DMPD(*)(+) assays decreased as the intensity of roasting increased, but the ability to prevent linoleic acid peroxidation was higher in the dark-roasted samples. Data suggest that melanoidins must be carefully considered when the relevance of coffee intake in human health is studied.
authors.affiliation: Dipartimento di Scienza degli Alimenti, Università di Napoli Federico II, Parco Gussone, 80055, Portici (Napoli), Italy.
authors.forename: Rosa Cinzia
authors.initials: RC
authors.lastname: Borrelli
authors.forename: Attilio
authors.initials: A
authors.lastname: Visconti
authors.forename: Carmela
authors.initials: C
authors.lastname: Mennella
authors.forename: Monica
authors.initials: M
authors.lastname: Anese
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Fogliano
mesh_terms: D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology*; D002850:Chromatography, Gel; D003069:Coffee / Q000737:chemistry*; D006358:Hot Temperature; D015416:Maillard Reaction; D008970:Molecular Weight; D011108:Polymers / Q000032:analysis / Q000494:pharmacology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000975:Antioxidants; D003069:Coffee; D011108:Polymers; C011908:melanoidin polymers