The Functional and Physicochemical Properties of Rice Protein Concentrate Subjected to Acetylation

Area of Science:

• Food Science
• Protein Chemistry
• Biochemistry

Background:

• Rice protein concentrate (RPC) is a valuable source of plant-based protein.
• Improving the functional properties of RPC can enhance its applications in food products.
• Chemical modifications offer a route to tailor protein functionality.

Purpose of the Study:

• To enhance the functional properties of rice protein concentrate (RPC) through acetylation.
• To analyze the impact of acetylation on RPC's chemical composition, digestibility, and protein structure.
• To evaluate changes in emulsifying properties, water-binding capacity, oil-absorption capacity, solubility, and foaming capacity.

Main Methods:

• Acetylation of rice protein concentrate using acetic anhydride.
• Analysis of chemical composition and protein content.
• Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for protein patterning.
• Fourier-transform infrared (FT-IR) spectroscopy for structural analysis.
• Assessment of protein digestibility, emulsifying properties, water-binding capacity, oil-absorption capacity, solubility, and foaming capacity.

Main Results:

• Acetylation increased protein content in RPC (80.90-83.10 g/100 g).
• SDS-PAGE showed a decrease in prolamin and glutelin content with increasing acetylation.
• FT-IR spectroscopy confirmed the presence of proteins, lipids, carbohydrates, and aromatic systems.
• Digestibility remained largely unchanged; emulsifying properties (at pH 8) and water-binding capacity significantly increased.
• Oil-absorption capacity was unaffected, while protein solubility slightly increased and foaming capacity decreased.

Conclusions:

• Acetylation is an effective method for improving key functional properties of rice protein concentrate, particularly emulsification and water-binding.
• The modification leads to a higher protein content and altered protein fraction distribution.
• RPC acetylation offers potential for enhanced utilization in food formulations without compromising digestibility.