The multi-scale structures and physicochemical properties changes of wheat starch during high-temperature Daqu...

Area of Science:

• Food Science
• Microbiology
• Biochemistry

Background:

• High-temperature Daqu is crucial for Jiangxiangxing Baijiu production.
• Wheat starch undergoes significant transformations during Daqu preparation.
• Understanding these starch changes is key to optimizing Baijiu quality.

Purpose of the Study:

• To investigate the multi-scale structural and physicochemical changes of wheat starch during high-temperature Daqu fermentation.
• To elucidate the impact of fermentation on starch properties relevant to Baijiu production.

Main Methods:

• Analysis of wheat starch structure and properties using various analytical techniques.
• Comparative study of starch changes during fermentation versus storage.
• Characterization of starch granule morphology, molecular weight, crystallinity, and thermal properties.

Main Results:

• Fermentation caused more significant wheat starch changes than storage.
• Starch surfaces were eroded, forming porous structures that facilitated enzymatic degradation.
• Molecular weight decreased, relative crystallinity and V-type structures increased due to annealing.
• Small starch granules (<10 μm) and amylose were preferentially degraded.

Conclusions:

• High-temperature Daqu fermentation induces substantial alterations in wheat starch.
• These modifications, including structural erosion and increased crystallinity, impact starch's thermal and pasting behaviors.
• Preferential degradation of smaller granules and amylose by microorganisms influences the final Baijiu characteristics.