Meeting Abstract - Poster Presentation

Determination of antioxidant capacity of wild rice using the ORAC assay
Y. QIU (1), T. Beta (1)
(1) University of Manitoba, Winnipeg, Manitoba, Canada
Cereal Foods World 53:A74

The study was aimed at evaluating the antioxidant activities of mixed, processed and raw wild rice. To extract antioxidant compounds from wild rice, aqueous acetone was used. The antioxidant activities of wild rice extracts were evaluated by using oxygen radical absorbance capacity (ORAC) assay. Compared to the white rice control, the results showed that all the wild rice samples (mixed, processed and raw) had much higher ORAC values which indicated higher antioxidant capacities. Among raw wild rice samples, Canadian lake wild rice had the highest ORAC value which reached 6064 µmol/100 g, whereas the ORAC values of other raw samples were above 4000 µmol/100 g. The mixed wild rice had a relatively low ORAC value of 2284 µmol/100 g due to the blending with white rice. Processing had a significant effect on the antioxidant level of wild rice. Quick-cooking wild rice prepared by soaking in water, cooking and drying had a significant reduction in antioxidant activity. But the scarified product exhibited a high ORAC value of 5799 µmol/100 g which is even higher than the average ORAC value of raw wild rice. It is likely that scarification, a process of scratching the surface of wild rice, enhanced the antioxidant capacity of wild rice.

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