Effects of Ultrafine Powderization and Hydrogen-Rich Water Extraction on Antioxidant Activity of Red Ginseng

Background: The health benefits of red ginseng are attributed to its antioxidant activity. Current information regarding the effects of ultrafine powdering and hydrogen-rich water extraction on the antioxidant activity of red ginseng is limited. Method and Results: Particle sizes, hydration properties, and antioxidant activity of red ginseng were investigated to determine its physicochemical characteristics. After ultrafine powdering, the particle size of the ultrafine red ginseng powder was reduced 2.5-fold and the water solubility index was increased by 7% compared to that of coarse red ginseng powder. Notably, the antioxidant activity of ultrafine red ginseng powder was increased as the water solubility index increased (p < 0.05). When ultrafine red ginseng powder was extracted with hydrogen-rich water, the total phenolic and flavonoid contents increased significantly (p < 0.05) because molecular hydrogen protected it from destruction by oxidation. Therefore, the antioxidant activity also increased significantly after hydrogen-rich water extraction (p < 0.05). Conclusions: This study demonstrated that the antioxidant activity of red ginseng can be increased by ultrafine powdering and hydrogen-rich water extraction.