Enhancing gel performance of surimi gels via emulsion co-stabilized with soy protein isolate and κ-carrageenan

This study aimed to prepare the emulsion co-stabilized via soy protein isolate (SPI) and κ-carrageenan (KC) and then investigate the effects of the SPI/KC emulsion on the gel performance of surimi gels. Particle size and optical microscopy findings revealed that the d 4,3 of emulsion droplets reached the minimum (11.800 ± 0.010 μm) at the appropriate SPI/KC ratio (95:5, w/w). The hardness, springiness, gel strength, whiteness, and water holding capacity of surimi gels were maximum (115.38 ± 2.33 N, 6.00 ± 0.14 mm, 8.59 ± 0.20 N, 74.80 ± 0.09, 91.96 ± 0.73%, respectively) when the SPI/KC emulsion was added. According to rheological tests, surimi gels with emulsions possessed higher viscoelastic modulus (G′ and G″). The addition of the SPI/KC emulsion reduced the creep rate (0.011 ± 0.002 s −1 ) and increased the recovery percentage (45.226 ± 0.497%) of surimi gels compared to the control gel with soybean oil (0.018 ± 0.003 s −1 and 42.026 ± 0.814%), indicating an increased rigidity and elasticity. In addition, the SPI/KC emulsion addition allowed small oil droplets in surimi gels to be uniformly distributed in a dense and ordered protein network. In conclusion, the SPI/KC emulsion optimized the gel characteristics of surimi gels, thereby providing a new idea for developing novel emulsified surimi products. • SPI/KC emulsion with tiny droplets was obtained at a 95:5 SPI/KC ratio. • SPI/KC emulsion increased the whiteness of surimi gels. • SPI/KC emulsion optimized the textural and rheological properties of surimi gels. • Tiny, evenly distributed oil droplets promoted the creation of dense gel networks.