Evaluation of Postprandial Glycemic Response and Physical Properties of High-Amylose Rice “Koshinokaori”

Abstract

This study evaluated the postprandial glycemic response and physical properties of the high-amylose rice, Koshinokaori (KK), cooked under different conditions. Twelve healthy subjects (Japanese, 6 males, 6 females) were given cooked, white KK rice or tomato chicken rice (TCR) using KK rice. The Japanese standard rice, Koshihikari (KH), was used as reference. All meals contained the same amount (50 g) of available carbohydrate. Blood glucose levels were measured at 0 (fasting), 15, 30, 45, 60, 90, and 120 min after each meal. The results from the cooked, white KK rice showed a significant difference in blood glucose variation at 60, 90, and 120 min and the incremental area under the curve (IAUC) of blood glucose concentration for KK cooked at optimal water to rice ratio was observed. Blood glucose variation and IAUC after intake of TCR-KK rice was lower than that after TCR-KH rice intake. Addition of 5% trehalose to KK rice resulted in a smaller decrease in adhesiveness and stickiness of cooked rice after 180 min at 20ºC. The addition of 5% trehalose to KK rice also produced favorable results in the sensory evaluation. KK rice produces favourable postprandial glycemic responses and physical properties under varied cooking condition and thus, may be beneficial in the prevention of lifestyle-related diseases such as type 2 diabetes.