Evaluation of oxidation in dried microencapsulated fish oils by a combination of adsorption and size exclusion chromatography

Adsorption and size exclusion chromatographies were applied to evaluate the oxidation of dried microencapsulated fish oils (DMFOs) and bulk fish oils during storage at 30 degrees C in light. DMFOs were prepared by freeze dryi ng emulsions containing fish oil, sodium caseinate and lactose, The analyti cal procedure used enabled concomitant quantitation of oxidized triacylglyc erol monomers formed during early oxidation and polymerization compounds, c haracteristic of advanced oxidation, whose sharp increase indicated the end of the induction period. Under the conditions used, evolution of polymers provided a better picture of the progress of oxidation as compared with the thiobarbituric acid reactive substances value and polyene index.