罗非鱼分离蛋白-卡拉胶复合乳液的稳定性研究

Studies on stability of tilapia protein isolate-carrageenan composite emulsion

该研究旨在提高罗非鱼分离蛋白(tilapia protein isolate,TPI)乳液的稳定性,拓展罗非鱼分离蛋白在食品工业中的应用。为此,以TPI为乳化剂,采用高压均质法制备乳液,探究不同卡拉胶质量浓度(0~2.5 mg/mL)对TPI乳液稳定性的影响。结果表明,添加卡拉胶能够显著增大乳液的Zeta电位绝对值(35.62 mV)(P<0.05)、表观黏度(Pa·s)及弹性模量G′。TPI与卡拉胶分子通过静电相互作用形成复合物,表面净电荷增加,阻碍了乳液液滴之间的聚集絮凝,提高了乳液的稳定性。同时,卡拉胶促进了蛋白在油水界面的吸附并形成了致密的界面膜。在模拟肠消化阶段中,添加1.5 mg/mL和2.0 mg/mL卡拉胶的乳液能够有效地抑制脂肪水解,提高乳液的消化稳定性。因此,卡拉胶可有效改善TPI乳液的物理稳定性和消化特性。该研究将为稳态化TPI乳液的开发以及TPI乳液基脂溶性活性物质递送体系的构建提供理论基础。

The purpose of this study was to improve the stability of tilapia protein isolate(TPI)emulsion and expand the application of TPI in the food industry.Therefore,the emulsion was prepared by high-pressure homogenization method with TPI as an emulsifier,and the effects of different carrageenan concentrations(0-0.25 mg/mL)on the stability of TPI emulsion were investigated.Results showed that the addition of carrageenan significantly increased the absolute value of Zeta potential(35.62 mV)(P<0.05),apparent viscosity(Pa·s),and elastic modulus G′of the emulsion.TPI and carrageenan molecules formed a complex through electrostatic interaction,and the net charge on the surface increased,which hindered the aggregation and flocculation between emulsion droplets and improved the stability of the emulsion.At the same time,carrageenan promoted the adsorption of protein at the oil-water interface and formed a dense interface film.In the simulated intestinal digestion stage,the emulsion with 1.5 mg/mL and 2.0 mg/mL carrageenan could effectively inhibit lipid hydrolysis and improve the digestive stability of the emulsion.Therefore,carrageenan can effectively improve the physical stability and digestibility of TPI emulsion.This study will provide a theoretical basis for the development of a stable TPI emulsion and the construction of a TPI emulsion-based fat-soluble active substance delivery system.