Impact of Heat-Moisture Treatment on Multi-Scale Structure, Functional Properties, and In Vitro Digestion of
Rong Zhou1, Jingyi Zheng1, Zhengyu Jin1
1State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China.
Foods (Basel, Switzerland)
|June 12, 2026
Summary
Heat-moisture treatment (HMT) of rice starch modifies its structure, reducing rapid digestion and increasing resistant starch. This process enhances low-glycemic index (GI) properties, offering potential for developing healthier food products.
Area of Science:
- Food Science
- Biochemistry
- Materials Science
Background:
- Rice starch is a primary carbohydrate source.
- Modifying starch structure can alter its digestibility and glycemic response.
- Developing low-glycemic index (GI) ingredients is crucial for managing metabolic health.
Purpose of the Study:
- To investigate the impact of heat-moisture treatment (HMT) on rice starch properties.
- To evaluate how HMT affects starch structure, digestibility, and estimated glycemic index (GI).
- To provide a basis for developing low-GI rice starch products.
Main Methods:
- Rice starch was subjected to heat-moisture treatment (HMT) at 100, 110, and 120 °C for 10 minutes.
- Analyzed multi-scale structure, functional properties (leaching rate, swelling power), and molecular weight.
- Assessed in vitro digestibility, including rapidly digestible starch (RDS), slowly digestible starch (SDS), resistant starch (RS), and digestion lag time.
- Determined estimated glycemic index (GI) using in vitro digestion data.
Main Results:
- HMT decreased starch leaching rate and swelling power.
- Relative crystallinity decreased, while short-range molecular order increased with higher HMT temperatures.
- Weight-average molecular weight decreased, and particle size increased.
- Amylopectin chain length distribution shifted towards shorter chains.
- Rapidly digestible starch content decreased significantly, while resistant starch content increased substantially (from 6.9% to 15.8% at 120 °C).
- Digestion lag time was prolonged, and the estimated GI of starch treated at 120 °C was 48.80, indicating suppressed digestibility.
Conclusions:
- Heat-moisture treatment effectively modifies rice starch structure and functionality.
- HMT significantly enhances resistant starch content and reduces the in vitro glycemic response of rice starch.
- Modified rice starch holds potential for developing low-GI food products.
