Evaluation of antioxidant capacity in coffees marketed in Colombia: Relationship with the extent of non-enzymatic browning

Abstract

Fifty-eight samples of commercial Colombian coffee with different characteristics (soluble, ground, decaffeinated, etc) were evaluated for antioxidant capacity (AC) (ABTS and FRAP), total soluble phenolics (TP), browning index (BI), color parameters (L∗, a∗, b∗, c∗ and h∗), HMF and furfural. The AC in Colombian coffees was very varied (164–1000, 100.8–885.9μmol of Trolox equiv/g and 12.5–127mg gallic acid equiv/g, respectively for ABTS, FRAP and TP). AC, TP, BI, color, HMF and furfural values were higher (p<0.05) in soluble coffees than in ground ones, showing the lyophilized samples which showed the highest average values. Significant lineal correlations (p<0.05) were found between AC and color parameters, BI, HMF. No significant (p<0.05) differences in the AC between the different types of coffee were found. This work confirms the direct relationship between the rate of non-enzymatic browning and antioxidant capacity.