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.
