Effects of dietary fiber from different particle sizes of wheat bran on myofibrillar protein structure

Area of Science:

• Food Science and Technology
• Biochemistry
• Materials Science

Background:

• Wheat bran dietary fiber (WBDF) is a significant agricultural by-product.
• Understanding the impact of WBDF particle size on protein functionality is crucial for food ingredient development.
• Myofibrillar proteins (MP) are key components in meat products, influencing texture and stability.

Purpose of the Study:

• To investigate how different particle sizes of wheat bran dietary fiber (WBDF) affect the physicochemical properties and structural conformation of myofibrillar protein (MP).
• To explore the potential of micronized WBDF as a functional ingredient in protein systems.
• To elucidate the mechanism by which WBDF influences MP stability.

Main Methods:

• Ultrafine comminution of WBDF to reduce particle size.
• Analysis of WBDF composition (monosaccharides).
• Measurement of water-holding capacity (WHC) and oil-holding capacity (OHC) of MP composite systems.
• Assessment of MP surface hydrophobicity and intrinsic fluorescence.
• Analysis of MP secondary structure (e.g., α-helix content) and thermal stability.

Main Results:

• Micronized WBDF (17.53 μm) significantly improved the water-holding and oil-holding capacities of MP.
• WBDF addition reduced MP surface hydrophobicity and induced structural changes, indicating hydrophilic shielding.
• Finer WBDF promoted a more ordered MP secondary structure, increasing α-helix content and thermal stability.
• Arabinoxylan-rich fibers formed a hydration shell around MP, masking hydrophobic domains.

Conclusions:

• Micronized WBDF acts as an effective filler and stabilizer for myofibrillar proteins.
• The "hydrophilic shielding" mechanism enhances protein stability and functional properties.
• This research provides a sustainable strategy for utilizing wheat by-products in meat gel systems and other food applications.