Instant coffee solutions were shown by electron paramagnetic resonance
(EPR) spectroscopy to act as prooxidants by enhancing the production
of ascorbyl radicals from ascorbic acid. The coffee solutions were als
o shown to act as scavengers of superoxide radicals in competition wit
h a spin trap. The radical scavenging capabilities of several componen
ts of coffee were similarly investigated. There was little difference
between the radical scavenging abilities of regular and decaffeinated
coffee solutions.