jf205388x_si_001.pdf (17.03 kB)
Influence of Coffee Roasting on the Incorporation of Phenolic Compounds into Melanoidins and Their Relationship with Antioxidant Activity of the Brew
journal contribution
posted on 2012-05-02, 00:00 authored by Daniel Perrone, Adriana Farah, Carmen M. DonangeloIn the present study, the influence of coffee roasting
on free
and melanoidin-bound phenolic compounds and their relationship with
the brews’ antioxidant activity (AA), evaluated by TRAP, TEAC,
and TRAP, were investigated. Changes in the relative content of free
chlorogenic acids (CGA), free lactones, and melanoidin-bound phenolic
acids during roasting indicate that phenolic compounds were incorporated
into melanoidins mainly at early stages of the process, being thereafter
partly oxidized to dihydrocaffeic acid, and degraded. Although less
than 1% of CGA in green coffee was incorporated into melanoidins during
roasting, the relative content of melanoidin-bound phenolic acids
increased significantly during this process, reaching up to 29% of
total phenolic compounds in brews from dark roasted coffees. Regardless
of the AA assay used and considering all roasting degrees, the overall
contribution of CGA to the AA of the whole brews was higher than that
of melanoidin-bound phenolic compounds. It was estimated that the
latter compounds contributed to 25–47% of the AA, depending
on the assay used.