Influence of pH-shifting combined with ultrasound on the structure and emulsification characteristics of coconut meal globulin

Abstract

Coconut meal globulin exhibited certain emulsifying properties. However, globulin was sensitive to environmental factors that lead to protein denaturation and aggregation, thus limiting their application. In the current work, globulin was modified using pH-shifting combined with ultrasound to improve the structural and emulsification properties. Results showed the pH-shifting combined with ultrasound treatment led to the exposure of internal hidden hydrophobic residues, disruption of hydrogen bonding. The surface hydrophobicity and molecular flexibility of globulin increased, along with improved fluorescence intensity. The combined treatment conditions boosted the interfacial protein adsorption content of globulin-based emulsions significantly. The resulting emulsions were uniformly dispersed without aggregation, exhibited optimal storage, thermal, and cold storage stability, similar to the performance of the sodium caseinate. This study provides an effective strategy for developing plant-based proteins as high-value emulsifiers, providing a potential alternative for sustainable food formulations.