F. Tubaro et al., THE ANTIOXIDANT CAPACITY OF COMPLEX-MIXTURES BY KINETIC-ANALYSIS OF CROCIN BLEACHING INHIBITION, Journal of the American Oil Chemists' Society, 73(2), 1996, pp. 173-179
The capability of a compound or of a mixture of compounds to quench pe
roxyl radicals was measured by analyzing the kinetics of the competiti
on of a parallel reaction where peroxyl radicals bleach the carotenoid
crocin. This kinetic approach, originally described for the analysis
of antioxidants reacting with hydroxyl radicals in water, was modified
by both decreasing the polarity of the solvent, thus allowing the ana
lysis of lipophilic compounds, and by substituting a source of peroxyl
radicals for the hydroxyl radical generating system. Single compounds
as well as complex mixtures were analyzed by kinetic data processing.
Overall antioxidant capacity, relative to that of a-tocopherol or of
its soluble analog Trolox C, was calculated. As examples of the use of
this test, the antioxidant capacities of a crude rosemary extract, Ma
illard reaction products, and virgin olive oils were measured.