Composition and stability of olive oil following partial crystallization

Extra virgin olive oils were separated into two fractions, one being liquid at 4 °C and one solid. Each of the oils and their associated fractions underwent analysis for fatty acid composition, analysis of the total antioxidant activity and stability towards oxidation when heated at 150 °C. The solid fraction contained greater amounts of saturated fatty acids, although analysis of the fatty acids on position 2, obtained via a pancreatic lipase treatment, showed similar total levels of unsaturated fatty acids for all fractions. Analysis of the antioxidant components showed that there was a higher proportion associated with the liquid fractions. This trend, in combination with the results of the heating trials of the oils and associated fractions, indicated that the liquid fraction was not more susceptible to oxidation. Hence it is possible to fractionate olive oil to give fractions with onset of melting differing by some 10 °C without compromising stability towards oxidation.