Relations between rice starch fine molecular and lamellar/crystalline structures
1School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Institutes of Agricultural Science and Technology Development of Yangzhou University, Yangzhou 225009, Jiangsu, China.
Food Chemistry
|March 19, 2021
Summary
Rice starch lamellar and crystalline structures significantly influence its properties. Chain-length distributions (CLDs) correlate with lamellar thickness and crystallinity, but molecular size does not.
Area of Science:
- Carbohydrate Chemistry
- Food Science
- Materials Science
Background:
- Starch's semi-crystalline lamellar structure dictates its physicochemical and digestion properties.
- Understanding starch lamellar structures is crucial for controlling its functionality in various applications.
Purpose of the Study:
- To investigate the lamellar and crystalline structures of 16 rice starches.
- To correlate these structures with starch chain-length distributions (CLDs) and molecular size distributions.
Main Methods:
- Analysis of starch lamellar and crystalline structures.
- Determination of starch chain-length distributions (CLDs).
- Assessment of starch molecular size distributions.
Main Results:
- Amorphous lamellar thickness correlates with short and medium amylose chains.
- Lamellar thickness and crystallinity are influenced by amylopectin chain lengths and relative lengths.
- Starch CLDs, but not molecular size distributions, correlate with lamellar ordering, fractal nature, and thickness polydispersity.
Conclusions:
- Starch chain-length distributions are key determinants of its semi-crystalline lamellar structure.
- Molecular size distributions do not correlate with starch lamellar/crystalline structures.
- This research provides insights into the molecular basis of starch lamellar organization.
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