Utilizing Synchrotron-Based X-ray Micro-Computed Tomography to Visualize the Microscopic Structure of Starch...

Area of Science:

• Food Science
• Materials Science
• Biotechnology

Background:

• Starch hydrogels are crucial in various industries.
• Understanding their microstructure is key to controlling properties.
• Traditional imaging methods have limitations.

Purpose of the Study:

• To visualize starch hydrogel microstructures using synchrotron X-ray micro-computed tomography (μCT).
• To compare μCT with Scanning Electron Microscopy (SEM) for hydrogel imaging.
• To investigate the effect of amylose content and cooking temperature on starch hydrogel structure.

Main Methods:

• Preparation of starch hydrogels from waxy maize starch (WMS), pea starch (PS), and high-amylose maize starch (HMS).
• Cooking of starches at 95 °C and 140 °C.
• Microstructural analysis using synchrotron-based X-ray micro-computed tomography (μCT) and Scanning Electron Microscopy (SEM).

Main Results:

• Different starch types and cooking temperatures yielded varying gelation outcomes and microstructures.
• High-amylose maize starch (HMS) cooked at 140 °C formed a rigid gel with high strength.
• μCT revealed detailed, three-dimensional microstructures with minimal sample shrinkage, outperforming SEM.
• Hydrogel structures were significantly influenced by starch swelling and dispersity.

Conclusions:

• Synchrotron-based μCT is a powerful, nondestructive technique for visualizing biopolymer hydrogel microstructures.
• μCT offers advantages in sample preparation and 3D reconstruction compared to SEM.
• This imaging approach aids in understanding structure-property relationships in starch-based materials.