Acta Scientiarum Polonorum Technologia Alimentaria

Material and methods. Carotenoids extracted from Phaffia rhodozyma and the astaxanthin standard was selected for the investigations. Antioxidant potential was evaluated by radical scavenging activity (DPPH^• and ABTS^•+ radicals) and in lipid oxidative stability measurements (Rancimat, Oxidograph and Schaal oven tests).

Results. It was found that the examined extracts presented a significantly higher ability to scavenge the DPPH^• radical in comparison to the ABTS^•+ radical. Evaluations of linoleic acid emulsion oxidative stability showed a higher antioxidant effect of the Phaffia rhodozyma extract than that of astaxanthin during 19 h of incubation. That potential however, was not detected in linoleic acid emulsion incubated for 96 h, where both additives accelerated oxidation process. In bulk sunflower oil a protective effect of Phaffia rhodozyma extract was observed. In both Rancimat and Oxidograph tests antioxidant activity measured using the induction period was evaluated. However, results of the Schaal oven test indicated that a 144 h incubation of sunflower oil offered a significantly better protection of the lipid against oxidation when the Phaffia rhodozyma extract was added.

Conclusions. On the basis of recorded results it was found that the Phaffia rhodozyma carotenoid extract showed moderate antioxidant properties, depending on the environmental conditions of methods used.