Effects of oxidative modification on thermal aggregation and gel properties of soy protein by malondialdehyde

Area of Science:

• Food Science
• Protein Chemistry
• Oxidative Stress

Background:

• Lipid peroxidation products can affect protein functionality.
• Understanding oxidative modification is crucial for food processing and quality.

Purpose of the Study:

• To investigate the impact of malondialdehyde (MDA), a lipid peroxidation product, on soy protein's thermal aggregation and gel properties.
• To determine how varying MDA concentrations influence soy protein structure and functionality.

Main Methods:

• Soy protein was incubated with increasing concentrations of MDA.
• Thermal denaturation and aggregation were analyzed.
• Gel properties including water holding capacity, hardness, and strength were measured.
• Microstructure of the protein gel network was examined.

Main Results:

• MDA significantly decreased particle size and thermal aggregate content during heat denaturation.
• Soy protein gel properties, including water holding capacity, hardness, and strength, were reduced by MDA modification.
• The protein gel network became coarser with increased interstice size and uneven distribution as MDA concentration rose.

Conclusions:

• Oxidative modification by MDA negatively impacts soy protein's thermal aggregation and gel-forming ability.
• MDA concentration is a key factor in determining the extent of soy protein modification and resulting functional property changes.