Resistant starch (RS) is not hydrolyzed into D-glucose in the small intestine and ferments in the large intestine. Rice (Oryza sativa L.) is a major source of carbohydrates and plays an important role in providing energy to the body. The purposes of this research were to elucidate the starch characteristics of different amylose contents in various rice cultivars developed by the National Institute of Crop Science and enhance use of resistant starch (RS)-containing “dodamssal” (DDS) rice as a health-promoting low-glycemic-index (GI) food.
Non-digestible starches (NDS) and native starches (NS) were isolated from four rice cultivars: Baegokchal (BOC), Ilmi (IM), Mimyeon (MM), and DDS. MM- and DDS-derived NS showed high amylose and low rapidly digestible starch contents as well as high slowly digestible starch and RS proportions. The BOC, IM, and MM starch crystals showed A-type X-ray diffractometry patterns. However, the DDS granules displayed a C-type crystallinity pattern with a predominant B-type and convex spherical shape. All the IM and BOC starches were hydrolyzed, with no remaining NDS residues. MM and DDS NDS showed longer average amylopectin chain length but lower molecular weight and viscosity than the NS. The DDS starch had the lowest digestibility and highest RS content, showing its potential to fight obesity and hyperglycemia.
Dr. Jiyoung Park received her Ph. D degree from Korea University, and a master’s degree from Pusan National University in Korea. The title of her doctoral dissertation is “ Prebiotic food starch characteristics and materialization fo Dodamssal”. She has worked as a research scientist at the National Institute of Crop Science of the Rural Development Administration since 2012. Her research is focusing on newly developed domestic crops, health food materials, food processing technology. She published 60 papers in domestic and international journals, and applied for 14 patents, of which 9 were registered.