Formation and in vitro starch digestibility of amylose-lipid complex using cooked rice starch and an emulsified formulation.

Adding fats to cooked starch creates molecular structures that make the starch harder for digestive enzymes to break down, more than starch retrogradation alone.

Adding 5% or more emulsified formulation to cooked rice starch reduces rapidly digestible starch by 20-30%, increases resistant starch by 15-25%, and lowers the estimated glycemic index due to structural changes that slow enzyme breakdown in laboratory conditions.

When rice starch is cooked and treated with a 5–10% emulsified formulation, its granules become thin, rounded, and amorphous with surface depressions, whereas untreated rice starch retains a more regular and crystalline structure.

Adding an emulsified formulation to cooked rice starch does not change how thick the starch mixture feels when poured, even though the starch becomes easier to digest.

Adding a 10% emulsified formulation to cooked rice starch increases the formation of amylose-lipid complexes, which is detected by a higher infrared absorption ratio at 995 cm⁻¹ compared to 1022 cm⁻¹, indicating a greater development of V-type crystalline structures.

Adding an emulsified formulation to cooked rice starch increases the amount of lipids bound to the starch while leaving other lipids unchanged, indicating that lipids are selectively incorporated into the starch structure.