Antioxidant and pro-oxidant activity of coffee as affected by torrefacto roast

Abstract

The addition of sugar at the end of the torrefacto roasting process could influence on the antioxidant and pro-oxidant properties of coffee because sugar is one of the main precursors of Maillard reaction. The aim of the work was to study and compare the antioxidant and pro-oxidant properties of some commercial roasted coffees which are selected to represent conventional roasted coffee and torrefacto roasted blends. When the percentage of torrefacto coffee was increased, the antioxidant activity increase and a slight tendency to decrease the pro-oxidant activity were observed. Moreover, a principal component analysis allowed to separate (a) brands by PC1 (46.9%) characterised by colour parameters defined by roast degree, and (b) torrefacto roast blends by PC2 (33.7%) characterised by antioxidant/pro-oxidant activity.