Heat-moisture modified blue wheat starch: Physicochemical properties modulated by its multi-scale structure

Area of Science:

• Food Science
• Material Science
• Biochemistry

Background:

• Starch modification is crucial for tailoring food properties.
• Heat-moisture treatment (HMT) is a physical method to alter starch structure.
• Understanding HMT effects on blue wheat starch is key for food applications.

Purpose of the Study:

• To investigate the impact of varying moisture contents (MCs) during HMT on blue wheat starch.
• To correlate structural changes with physicochemical properties.
• To assess the potential of HMT-modified starch in food products.

Main Methods:

• Blue wheat starch subjected to HMT with different MCs.
• Evaluation of physicochemical properties (crystallinity, thermal properties, viscosity).
• Analysis of multi-scale structural changes (lamellae, hydrogen bonding, amylopectin chains).

Main Results:

• HMT at lower MCs preserved phenolics and starch brightness.
• Increased MC led to structural disruptions: reduced crystallinity, loosened lamellae, broken hydrogen bonds, and debranching.
• Modified starches exhibited higher transition temperatures and lower enthalpy.
• 15% MC HMT starch showed increased peak viscosity due to compact lamellae and homogenous electron distribution.
• All HMT starches demonstrated reduced breakdown and setback.

Conclusions:

• HMT effectively modifies blue wheat starch structure and properties.
• Specific MCs during HMT can optimize starch functionality for food applications.
• HMT-modified starches are promising for developing healthy, anti-staling food ingredients.