Improvement of the quality of surimi gels by high internal-phase emulsions prepared with fish oil and Zein peptide nanoparticles

High internal-phase emulsions (HIPEs) could be utilized to improve the surimi quality. However, the effects of Zein peptide nanoparticles (ZPNs) on the stability of HIPEs encapsulating fish oil and HIPEs stabilized by ZPNs (ZPNHIPEs) on surimi gels are still unclear. Therefore, the effect of ZPNs on stabilizing HIPEs and whether ZPNHIPEs could contribute to surimi gelation behaviors were analyzed. The turbidity of ZPNs was smaller than that of corn protein nanoparticles at the same concentration and increased with the rise in ZPN concentrations due to aggregation. Besides, the stability of HIPEs increased with the increase in ZPN concentrations. The addition of ZPNs at 1% could stabilize HIPEs, unlike those at 4% due to peptide aggregation. Moreover, the ZPN interactions in the gel matrix between ZPNHIPEs and surimi were beneficial for improving the texture of surimi gels and the formation of a strong gel structure and elastic behavior, especially at 5% ZPNHIPEs. This work could broaden the potential application of ZPNHIPEs prepared with fish oil to enhance the quality of surimi in the food industry.