One-step method for modification of soy protein isolate and preparation of stable protein emulsions by industrial-scale high-energy fluidic microfluidizer.

Current research methods remain confined to a model of modifying the protein first and then preparing the emulsion, requiring multiple steps and cycles. To address this challenge, a one-step strategy was developed using a high-energy fluidic microfluidizer (HEFM) to simultaneously solubilize the soy protein isolate and fabricate stable emulsions. The HEFM increased the solubility of the soy protein isolate from 30.9% to 92.3%, while reducing the particle diameter from 53.0 μm (D[4,3]) to 0.4 μm. Structural analysis revealed that HEFM promoted a conversion of β-sheet to α-helix and exposed the hydrophobic residues. These changes facilitated rapid adsorption of the soy protein isolate to the oil-water interfaces, resulting in the formation of substantial and resilient interfacial films. The HEFM co-processing of protein-oil-water mixtures yielded emulsions exhibiting exceptional storage stability with no phase separation after 40 days. This research may establish a transformative technology for concurrent protein modification and emulsion fabrication.