Coffee can act as an antioxidant under certain conditions, according to a new study that could lead to a deeper understanding of the brewing process, as well as its potential health benefits.

Researchers at the Monash University in collaboration with Italian coffee roasting company Illycaffe, have conducted the most comprehensive study to date on how free radicals and antioxidants behave during every stage of the coffee brewing process, from intact bean to coffee brew.

They observed the behaviour of free radicals - unstable molecules that seek electrons for stability and are known to cause cellular and DNA damage in the human body - in the coffee brewing process.

For the first time it was discovered that under certain conditions coffee can act as an antioxidant, a compound found in foods that helps stabilise free radicals.

The findings, published in the journal PLOS ONE, will lead to a deeper understanding of the brewing process, as well as the potential health benefits of coffee.

Chief Chemist of Illycaffe, Luciano Navarini, approached Monash physicist Gordon Troup, from the School of Physics and Astronomy, and his team in 2012 to conduct the research using state-of-the-art EPR (Electron Paramagnetic Resonance) Spectroscopy.

The most important aim of this research was to better understand the development of stable free radicals during the roasting process and the possible influence exerted by developed radicals on the well-documented coffee antioxidant properties.

"We also wanted to evidence possible coffee constituents as a source of antioxidant activity," Navarini said.

"Our research studied both the Arabica coffee bean itself and what happens to its stable free radical and antioxidant properties during the brewing process," Troup said.

"The findings provide a better understanding of the potential health benefits of coffee, as well as a deeper knowledge of the roasting process - ultimately leading to the highest quality cup of coffee," Troup added.