1.4. Heat–moisture treatment
Rice starch and flour samples were adjusted to the desired moisture content (20, 25 or 30%) by soaking 200 g of starch in 600 ml of water overnight at 4 ◦C. The excess water in equilibrated slurry was then drawn out by vacuum suction to obtain a cake with moisture content around 40%. The cake was then air-dried to allow the moisture content to drop to the desired level. Moist samples (native and moistened rice starches and flours) in 250 ml screw-capped bottles were heated at 100 ◦C for 16 h. After HMT, the starches were dried at 40 ◦C overnight. Untreated rice starch and flour were used as controls.