Research has found that it is the outer layer (hull) of the barley grain that has the highest concentration of beneficial phenolic compounds. Therefore to maximize your nutrition, buy whole grain when possible. This ORAC value test was for crushed wholemeal barley flour which was purchased in Norway. The country of origin for the grain was also Norway.
How much antioxidants there are in barley is about 3x higher than wholemeal wheat flour and slightly higher than millet and maize. The antioxidant content of barley includes benzoic and cinnamic acid, proanthocyanidins, flavones, flavanones, chalcones, and flavonols.
Research Support, Non-U.S. Gov't: Carlsen MH, Halvorsen BL, Holte K, et al. Nutrition Journal NIH Jan 2010