Better Coffee Through Spectroscopy

Researchers at Monash University (Melbourne, Australia) used electron paramagnetic resonance (EPR) spectroscopy and in vitro antiradical assays to study the radical content and antiradical capacity of Coffea arabica sourced from an industrial roasting plant (1). In doing so, the researchers were able to demonstrate how free radicals and antioxidants behave during every stage of the coffee brewing process, from intact bean to coffee brew.

The findings, published in PLOS ONE, characterize the radical content and antioxidant capacity of brews prepared from Arabica coffee beans.

The research demonstrated that a number of stable radical species are formed during roasting and their intensity profile varies with roasting time and upon subsequent grinding and ageing. The researchers noted that the stable radical(s) present within dark-roasted beans are unrelated to the antiradical activity of coffee brewed from those beans; however, they determined that this does not preclude a functional role for these radical species in non-antioxidant mechanisms in vivo following coffee consumption, or in variations to flavor profile during storage and ageing.

Reference

(1) G.J. Troup, L Navarini, F.S. Liverani, S.C. Drew, PLOS ONE,  (2015).