The antioxidant activity of pomegranate juices was evaluated by four different methods
(ABTS, DPPH, DMPD, and FRAP) and compared to those of red wine and a green tea infusion.
Commercial pomegranate juices showed an antioxidant activity (18-20 TEAC) three times
higher than those of red wine and green tea (6-8 TEAC). The activity was higher in
commercial juices extracted from whole pomegranates than in experimental juices obtained
from the arils only (12-14 TEAC). HPLC-DAD and HPLC-MS analyses of the juices revealed
that commercial juices contained the pomegranate tannin punicalagin (1500-1900 mg/L)
while only traces of this compound were detected in the experimental juice obtained
from arils in the laboratory. This shows that pomegranate industrial processing extracts
some of the hydrolyzable tannins present in the fruit rind. This could account for
the higher antioxidant activity of commercial juices compared to the experimental
ones. In addition, anthocyanins, ellagic acid derivatives, and hydrolyzable tannins
were detected and quantified in the pomegranate juices.