Abstract:
To improve the texture stability of low-salt fermented meat products, 0.4% transglutaminase (TGase), 0.075%
γ-polyglutamic acid (
γ-PGA), and 0.075%
γ-PGA+0.4% TGase were used to replace NaCl (from 2% to 0.5%) in this study. Through texture, water-holding capacity, chemical forces, and secondary structure indicators, the regulatory effects of the above treatments on the protein conformation and quality of low-salt sausages were systematically evaluated. The results showed that the salt reduction treatment in the LS group (NaCl addition of 0.5%) significantly increased the protein particle size from 405.36 nm to 1970.77 nm (
P<0.05), and significantly reduced the absolute value of the Zeta potential and surface hydrophobicity of the protein (
P<0.05), which in turn led to a decrease in water-holding capacity and texture deterioration of the product. The combination of
γ-PGA (0.075%) and TGase (0.4%) not only inhibited the excessive protein aggregation caused by TGase alone, but also induced protein refolding and enhanced hydrophobic interactions. Macroscopically, the water-holding capacity of the combined group sausages was significantly improved (
P<0.05), the color was improved, and the hardness, elasticity, and chewiness were close to or even exceeded those of the high-salt (HS) group. However, the use of
γ-PGA or TGase alone could enhance the hardness and elasticity of low-salt fermented sausages, but the effect was not significant when compared with the HS group (
P>0.05). Therefore, the combined strategy of 0.075%
γ-PGA and 0.4% TGase can significantly optimize the protein conformation and intermolecular forces, effectively compensate for the texture and quality deterioration caused by salt reduction, and provide a new strategy for the development of low-salt fermented meat products.