The antioxidant activity of coffee brew extracts towards inorganic radicals was also assessed using Frémy’s salt. Coffee extracts (0.075 2.0 mg/mL) were reacted with an equal volume of Frémy’s salt (1 mM in 50 mM phosphate buffer; pH 7.4) and then freeradical intensity was monitored immediately (t = 0) and at 30 (t = 30) min thereafter. The EPR spectrometer operating conditions comprised: field modulation, 100 kHz; modulation amplitude, 3 gauss; time constant, 2.56 ms; conversion time, 10.49 ms and attenuation, 10 dB. The reference was Trolox (0.006–0.05 mg/mL) reacted with an equal volume of Frémy’s salt (1 mM) in phosphate buffer for 30 min. The antioxidant activity of coffee brew extract determined using Frémy’s salt is expressed as mmol equivalents of Trolox/g of coffee brew extract (dry weight).