离子强度对煮制前后猪肉胶原蛋白乳化特性的影响

为研究离子强度对煮制前后猪肉胶原蛋白乳化特性的影响，测定煮制前后不同NaCl浓度（0.0、0.2、0.4、0.6 mol/L）猪肉可溶性胶原蛋白和不溶性胶原蛋白的乳化特性，包括乳化活性指数（emulsification activity index，EAI）、乳化稳定性指数（emulsion stability index，ESI）、黏度及乳化液微观结构，同时测定猪肉胶原蛋白溶解度。结果表明：随着介质离子强度的提高，猪肉可溶性胶原蛋白溶解度降低，黏度增大，EAI先升高后降低，ESI先降低后升高；猪肉不溶性胶原蛋白溶解度升高，黏度增大，EAI、ESI均呈先升高后降低趋势。改变胶原蛋白的离子强度或对胶原蛋白进行热处理，均能使猪肉可溶性胶原蛋白和不溶性胶原蛋白的乳化特性发生显著变化。

Effect of Ionic Strength on the Emulsification Characteristics of Pork Collagen before and after Cooking

In order to explore the effect of ionic strength on the emulsification characteristics of pork collagen before and after cooking, this study evaluated the emulsification properties of soluble and insoluble pork collagen in the presence of different concentrations of NaCl (0.0, 0.2, 0.4 and 0.6 mol/L), including emulsification activity index (EAI), emulsion stability index (ESI), viscosity, emulsion microstructure, and solubility. The results showed that with increasing ionic strength, the solubility of soluble collagen decreased, the viscosity increased, EAI first increased and then decreased, while ESI exhibited the opposite trend; the solubility and viscosity of insoluble collagen increased, and both EAI and ESI showed a trend of first increase and then decrease. In conclusion, the change in ionic strength or heat treatment could significantly change the emulsification characteristics of both soluble and insoluble pork collagen.