Healthier red and blackrice : not your ordinary staple food

The Philippines is experiencing increased prevalence of chronic illness such as career, cardiovascular disease, and diabetes. Reactive cell-damaging free radicals are implicated in these disease. To help address the challenge of slowing down the occurrence of these dreadful illness, increased research efforts are focused on functional foods such as antioxidants. Rice is the staple food in the country but white rice is the form commonly consumed. However, there are pigmented rice varieties containing potent antioxidants. To explore the potential of pigmented rice as functional food, a total of 70 black and red rice varieties collected from all over the country were characterized for proximate composition, anthocyanin, total phenolic content, and antioxidant activity. Unpolished forms had erude protein of 5.87-11.12% (red) and 6.12-11.63% (black); crude ash of 0.77-1.79% (red) and 0.90-1.84% (black); crude fiber of 0.65-2.07% (red) and 0.68-1.94% (black). Total anthocyanin content of the unpolished black rice was 43.25-4742.38mg/kg, with Ballatinaw having the highest value. Unpolished red rice had lower values at 9.37-598.30 mg/kg. Total phenolic content of the unpolished forms of red rices ranged from 0.62-5.91 mg gallic acid equivalent(GAE)/g while black rices had 0.92-7.40 mg/kg. Based on DPPH radical scavenging assay the total antioxidant activity was 77.95-94.22% for unpolished red rice and 78.17-90.71% for unpolished black rice. The best DPPH radical scavengers were the red Kapukaw and black Galo. Since most of these health-promoting components were significantly lost upon polishing , the unpolished forms must be consumed in order to maximize the health benefits of pigmented rice. This study shows that in addition to good-quality protein and relatively high proximate content, red and black rice are excellent sources of antioxidants. Aside from being potential parents for the development of new rice varieties with good eating and nutritional qualities, these rices should be promoted as functional foods.