Gordon J. Troup(a), Ruth Oliver(b) , Laura O’Dea(b), John Boas(a), and Steven J. Langford (b)
a) School of Physics, and b) School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
Green Ginger Wine (‘green’ in the sense of ‘fresh’) has been sold in the UK since 1740. These days there are two varieties, ‘original’ (O: 13.9% alc/vol) and ‘special’ (S: 18% alc/vol). Fresh ginger roots are crushed, and an extract made with wine spirit (mainly ethyl alcohol). Colourant and sugars are added, and maturing now takes place in stainless steel vessels.
The extract contains Gingerol, a single phenolic (related to capsaicin, the ‘hot’ in chillies). Therefore a free radical signal was expected to be observed by EPR, albeit smaller than from polyphenols in grape wines. Also, the gingerol should have an antioxidant action.
EPR was carried out at 77K temperature with a Bruker spectrometer operating at X-band
( ~9.4 GHz.). The O and S samples had been cold evaporated to 20% of original volume to increase signal to noise ratio. A strong Mn2+ signal, a small Fe3+ signal, and the expected small free radical signal were observed. The Mn2+ would contribute to antioxidant efficiency. The O and S spectra were identical, so only the O green ginger wine antioxidant efficiency was determined, using the method described in  previously used.
The antioxidant efficiency measured was 94 +/- 2%. This is comparable with that of vitamins E and C measured by the same method.
Mn2+ is necessary for us to make the antioxidant superoxide dismutase (SOD2). The antioxidant action of green ginger wine is meaningful and significant remembering moderation at all times!:
 I Cheah, J.Kelly, S.J.Langford and G.J.Troup, Proc.27th Ann.Cond Matter Mater. Meeting, http://aip.org.au/content/publications (2003)