Improving the Efficiency of Proteolysis in Soybean Isolate: Cold Plasma Treatment

To address the low efficiency in traditional enzymatic hydrolysis, cold plasma-assisted soy protein isolate (SPI-CP) was used to explore the mechanism of cold plasma on the efficiency of SPI hydrolysis. Results showed that compared to SPI treated only with enzymatic hydrolysis, SPI-CP exhibited an increase in hydrolysis degree from 16.1 to 27.2% and solubility from 46.0 to 66.0%. The dispersion system of SPI-CP solution was more stable, with reduced surface hydrophobicity index from 3219.36 to 3008.89 and a decrease in particle size from 3500 to 500 nm. Protein structure analysis revealed that cold plasma caused the unfolding of SPI’s primary structure, resulting in more extended peptide chains. The distribution of high molecular weight proteins in SPI-CP decreases, making small molecular weight proteins and peptides more easily hydrolyzed. Cold plasma technology provides a theoretical foundation for protein hydrolysis and peptide preparation.