Rice amylopectin fine structure variability affects starch digestion properties
Mustapha Benmoussa1, Karen A K Moldenhauer, Bruce R Hamaker
1Whistler Center for Carbohydrate Research and Department of Food Science, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN 47907, USA. mbenmous@purdue.edu
Journal of Agricultural and Food Chemistry
|January 31, 2007
Summary
Researchers explored rice cultivars for low glycemic response by analyzing starch properties. Rapid Viscoanalyzer (RVA) breakdown viscosity effectively predicts starch digestibility, aiding in developing low glycemic rice.
Area of Science:
- Agricultural Science
- Food Science and Technology
- Biochemistry
Background:
- Rice is a staple food, but its high glycemic index can be a health concern.
- Starch digestibility in rice influences its glycemic response.
- Amylopectin structure and pasting properties are key factors affecting starch digestion.
Purpose of the Study:
- To investigate the relationship between rice starch digestibility and amylopectin fine structure.
- To explore the potential of Rapid Viscoanalyzer (RVA) as a tool for screening rice cultivars with varying starch digestion properties.
- To identify rice cultivars with low glycemic response and inform breeding strategies for low glycemic rice.
Main Methods:
- Selected twelve rice cultivars with varied RVA pasting breakdown and similar amylose content.
- Analyzed in vitro starch digestibility using the Englyst assay.
- Characterized pasting properties using RVA and debranched amylopectin structure.
Main Results:
- Rapidly digestible starch (RDS) correlated negatively with long/intermediate amylopectin chains and positively with very short chains.
- Slowly digestible starch (SDS) showed the opposite correlation pattern with amylopectin chain lengths.
- RVA breakdown viscosity strongly correlated with both RDS and SDS, indicating its predictive potential for starch digestion.
Conclusions:
- Amylopectin fine structure variability underlies differences in starch digestion properties among rice cultivars.
- RVA is a viable screening tool for assessing starch digestion and identifying rice with low glycemic potential.
- Findings support breeding strategies for developing new rice cultivars with improved glycemic response.
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