Characterization and salt reduction evaluation of Haematococcus pluvialis protein microgel–Gum arabic complex-stabilized high internal phase Pickering emulsion for sodium chloride delivery

In this study, a food-grade high internal phase Pickering emulsion (HIPPE) system capable of sodium chloride (NaCl) delivery was developed, aiming to fabricate low-sodium semi-solid foods and reduce dietary sodium intake. To enhance the storage stability and improve the perception of salty taste, HIPPEs containing NaCl were successfully fabricated using Haematococcus pluvialis protein microgel (HPPM) and gum Arabic (GA). The HPPM/GA mass ratio effect on NaCl-containing HIPPEs stability was investigated and the mechanism was analyzed through interfacial properties. It was found that the HPPM-GA complex demonstrated long-term emulsion stability under high salinity. This complex effectively anchored at the interface, which not only reduced the interfacial tension but also formed an interfacial film. Optimal salt retention was achieved at a 7:3 HPPM/GA mass ratio, with retention time increasing from 14.00 to 26.60 s (P < 0.05). Friction test results demonstrated that HIPPEs with a HPPM/GA mass ratio of 7:3 exhibited a distinct tribological profile distinguished by a lower interfacial pressure threshold. It was probably that oral shear forces induced droplet rearrangement, thereby modulating Na + release and prolonging salty taste perception. This research provided a reference for the development of low sodium semi-solid dipping food based on the transportation of NaCl in emulsion.