Contribution of the phenolic fraction to the antioxidant activity and oxidative stability of olive oil.
Antioxidant activity of the phenolic fraction of extra virgin olive oil (EVOO) was measured by means of a chemical and an electrochemical method. Both methods were tested in predicting the oxidative spoilage and stability to oxidation of 22 EVOO samples and resulted correlated with peroxide values and oxidative stability measured by Rancimat. The main phenolic compounds of EVOOs were detected by HRGC. To study the contribution of single polyphenols (PPs) to antioxidant activity of phenolic fraction and oxidative stability of EVOOs, multivariate statistical analyses were applied on HRGC data. An isomer of oleuropein aglycon was shown to affect significantly antioxidant activity of phenolic fraction but not oil stability to oxidation. No individual compounds was identified as the main cause of the overall antioxidant activity, and the total polyphenol determination by the Folin reagent was better correlated to antioxidant activity and oxidative stability than each tested PP or PPs groups such as o-diphenols.
Del Carlo
M
M
Department of Food Science, University of Teramo, Via Carlo R. Lerici 1, Mosciano Stazione, 64023 Teramo, Italy. delcarlo@unite.it
Sacchetti
G
G
Di Mattia
C
C
Compagnone
D
D
Mastrocola
D
D
Liberatore
L
L
Cichelli
A
A
D000975:Antioxidants / Q000032:analysis* / Q000737:chemistry; D002849:Chromatography, Gas; D004355:Drug Stability; D005419:Flavonoids / Q000032:analysis; D005519:Food Preservation; D007202:Indicators and Reagents; D008982:Molybdenum; D000069463:Olive Oil; D010084:Oxidation-Reduction; D010636:Phenols / Q000032:analysis* / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry*; D059808:Polyphenols; D017973:Tungsten Compounds
D000975:Antioxidants; D005419:Flavonoids; C029556:Folin's phenol reagent; D007202:Indicators and Reagents; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils; D059808:Polyphenols; D017973:Tungsten Compounds; D008982:Molybdenum