Highly cost-effective wheat starch-stearic acid complexes enabled by microwave processing: Structural properties,...

Area of Science:

• Food Science
• Materials Science
• Biophysics

Background:

• Traditional water bath heating is less efficient for preparing wheat starch-stearic acid (WS-SA) complexes.
• Detailed evaluations of time, energy, and quality, along with anti-digestion mechanisms, require further investigation for MW-processed WS-SA.

Purpose of the Study:

• To evaluate the time-energy-quality efficiency of microwave (MW) processing for WS-SA complexes.
• To elucidate the anti-digestion mechanisms of MW-processed WS-SA from a molecular perspective.

Main Methods:

• Microwave (MW) and water bath (WB) heating for WS-SA complex preparation.
• Physicochemical characterization including crystallinity, thermal stability, and complex index.
• Molecular dynamics (MD) simulations to analyze molecular interactions and structure.
• Solvent-accessible surface area and water status analysis.

Main Results:

• MW processing saved 95% time and 73% energy compared to WB.
• MW-processed WS-SA complexes exhibited higher relative crystallinity, ordered structure, thermal stability, complex index, and resistant starch content.
• MD simulations revealed MW treatment accelerated amylose-stearic acid binding, forming stable helical structures via hydrogen and van der Waals forces.
• Denser structures in MW-processed complexes reduced water solvation and mobility, enhancing resistance to enzymatic hydrolysis.

Conclusions:

• MW heating is a highly cost-effective and efficient method for preparing WS-SA complexes with improved physicochemical properties.
• The enhanced anti-digestion properties of MW-processed WS-SA are attributed to a denser molecular structure that limits water accessibility and enzymatic activity.
• This study provides molecular-level insights into the anti-digestion mechanisms, promoting MW heating for starchy food processing.