Effect of sonication on structural and functional characteristics of protein concentrate obtained from manipur black rice (Oryza sativa L.)

The black rice manipur protein concentrate (BRPC) was ultrasonicated at intervals of 5, 15, 25, and 35 min. Ultrasonication treatment profoundly altered the structure and functionality of BRPC while enhancing the solubility and emulsifying activity index of the material. Particle size, surface hydrophobicity, the secondary structure of the protein, and the fraction of α-helix and β-sheet structures were altered by US treatment. All sonicated samples showed increased surface hydrophobicity and solubility, which further enhanced their functional qualities. The ability of BRPC to act as an efficient emulsifier, thus qualifying it for use in food processing applications, can be established from the increase in EAI with ultrasonication time. The molecular weight of BRPC did not change after ultrasonication. These results suggest that a high-power ultrasonic technique is feasible for modifying the structural and functional properties of Black Rice Manipuri protein, thus potentially creating its application in various industries, food, and pharmaceutical applications.