Comparative studies on physicochemical and structural properties of rice proteins

Area of Science:

• Food Science and Technology
• Biochemistry
• Nutritional Science

Background:

• Rice (Oryza sativa L.) is a vital global food source.
• Rice proteins possess significant nutritional and functional benefits.
• Protein characteristics evolve throughout rice grain development stages.

Purpose of the Study:

• To investigate the impact of grain maturity on rice protein properties.
• To compare physicochemical and structural characteristics of young and mature rice proteins.
• To analyze four distinct rice varieties: Jasmine Rice 105, Hom Warin, RD6, and Hom Naka.

Main Methods:

• Protein content analysis
• Protein solubility assessment
• Molecular weight distribution profiling
• Amino acid composition determination
• Secondary structure analysis (e.g., β-sheet content)

Main Results:

• Young rice proteins exhibited higher protein content and solubility, especially from Y-HNKP and Y-IRP57514 varieties.
• Mature rice proteins, particularly M-HNKP, showed increased β-sheet structures and lower solubility due to aggregation.
• Young rice grains (Y-RDP6) had superior essential amino acid profiles, while mature grains showed complex molecular weight distributions.

Conclusions:

• Significant differences in protein characteristics exist between young and mature rice grains.
• Young rice proteins are suitable for high-protein foods and supplements due to high content, solubility, and bioavailability.
• Mature rice proteins offer structural stability for applications requiring enhanced storage stability.