Ultrasonic pre-treatment followed by glycation modifies chickpea protein isolate: structural transformation, pickering emulsion stability and gel properties.

Chickpea protein isolate (CPI) has high nutritional value, but its limited functionality constrains its use in novel applications. This study developed Pickering emulsions stabilized by CPI modified through heating, ultrasonication, glycation with, dextran or their combination for people with dysphagia. Glycation modification was confirmed by degree of glycation, Fourier-transform infrared spectroscopy and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Structural analyses confirmed that ultrasonic pre-treatment facilitated CPI unfolding, as evidenced by increased surface hydrophobicity and a slight red-shift in the λmax of fluorescence emissions, facilitating covalent conjugation with dextran. The conjugates obtained from the combined ultrasonication and glycation treatment (U-glycation) showed the lowest interfacial tension, confirming its superior interfacial activity. U-glycation CPI emulsions had the smallest droplet size (13.91 ± 0.04 μm), representing a 35.57% decrease compared to the control and a 56.60% decrease relative to the heat, and showed the highest stability against coalescence and centrifugation, as evidenced by the lowest turbiscan stability index (an 84.97% decrease relative to the control) and against centrifugal stability index of 49.06% ± 0.18%, respectively. Improved rheological properties, including higher viscosity and elastic modulus, were also observed, indicating a robust gel network. Furthermore, the U-glycation emulsion gel demonstrated textural properties suitable for dysphagia diets (hardness 8.73 ± 0.67 g) and was categorized as Level 3 based on International Dysphagia Diet Standardization Initiative framework. This study demonstrates that ultrasound pre-treatment followed by glycation is a promising strategy for enhancing the functional properties of plant proteins, with potential applications in dysphagia foods and clean-label food products.