Research on the Performance and Structural Characteristics of Metal Salt Ion-regulated Sugar-based Fish Gelatin Emulsion Gel

In the pursuit of developing high-quality low-salt fish gelatin emulsion gel products, this study undertook a comprehensive investigation into the effects of varying concentration gradients of potassium chloride (KCl) and calcium chloride (CaCl₂) on the gel properties and structural characteristics of glycosylated fish gelatin emulsion gels. Specifically, the concentration gradients examined were 100, 200, 400, and 800 mmol/L. A multifaceted experimental approach was employed, encompassing analyses of particle size, zeta potential, texture profile analysis (TPA), water holding capacity, rheological properties, and scanning electron microscopy (SEM). The results demonstrated that as the salt ion concentration increased, several key parameters exhibited significant changes. The absolute value of Zeta potential, along with gel strength, hardness, adhesiveness, chewiness, and water holding capacity of the glycosylated fish gelatin emulsion gels, were all markedly reduced. In contrast, the particle size displayed an increasing trend. Furthermore, the impact of CaCl₂ on the gel properties was substantially more pronounced than that of KCl. Under conditions of high salt ion concentration (800 mmol/L), the viscoelasticity and deformation resistance of the emulsion gels were significantly compromised. The gel network structure became loosened, and the formation process was considerably hindered. The findings revealed that excess salt ions disrupted hydrogen bonding and hydrophobic interactions, thereby inhibiting protein cross - linking and ultimately leading to a reduction in the properties of the emulsion gels.