Effect of Soybean Meal Proteins on Gel Properties of Silver Carp Surimi

The influence of soybean meal protein addition to the gel properties of silver carp surimi was studied, and the potential causes were further analyzed from the perspective of chemical forces and protein secondary structures. The surimi gels were prepared by the addition of 0%, 0.5%, 1.0%, 1.5% and 2.0% of soybean meal protein, respectively, to the frozen surimi samples of silver carp. The water-holding capacity, cooking loss rate, whiteness value, texture characteristics, sensory quality, chemical strength, total sulfhydryl content and protein secondary structure of surimi gel were measured by a texture analyzer and Fourier transform infrared spectrometer. The results showed that when the amount of soybean meal protein accounted for 1.5% of the frozen silver carp surimi, the water holding capacity, hardness, springiness, cohesiveness and chewiness of the surimi gel increased to the maximum values of 87.59%±1.44%, 381.70±7.64 g, 12.41±0.67 mm, 0.89±0.02 and 38.60±0.14 mJ, respectively, while the cooking loss rate decreased to the minimum value of 10.20%±0.52%, the sensory quality reached the best, and the whiteness value decreased slightly. This could be explained that the addition of 1.5% soybean meal protein led to a maximum hydrophobic interaction and total sulfhydryl content of surimi gel, and a tight gel three-dimensional network structure was formed. Moreover, the addition of soybean meal protein had little effect on the secondary structure of surimi protein. Therefore, the addition of 1.5% soybean meal protein effectively improved the gelation properties of surimi products.