Enhanced acidic stability of O/W emulsions by synergistic interactions between okara protein and carboxymethyl cellulose

作者：Cai, Yongjian; Huang, Lihua; Tao, Xia; Su, Jiaqi; Xiao, Chuqiao; Zhao, Mouming; Zhao, Qiangzhong^*; van der Meeren, Paul

来源：Food Science and Technology, 2021, 146: 111439.

DOI：10.1016/j.lwt.2021.111439

• Protein-polysaccharide interaction
• Electrostatic complexation
• Emulsion properties
• Stability

The application of okara protein (OP) in emulsions is yet to be fully explored. The present work aims to investigate the effects of carboxymethyl cellulose (CMC) - OP complexes on the emulsion properties and emulsion stability. CMC (0-5 g/kg) was introduced to electrostatically interact with the OP (10 g/kg) at pH 4.0, and then O/W emulsions (1:9, g/g) were prepared by the complexes and systematically characterized. As the CMC concentration increased from 0 to 5 g/kg, the particle size of the OP-CMC complexes decreased from 6400 to 380 nm, while the zeta-potential decreased from 1 to -28 mV. As for the emulsions, their zeta-potential was reduced from -1 to -28 mV while their droplet size decreased from 201 to 10 mu m with less flocculation. The surface protein content decreased from 97% to 73% while less creaming was observed in the fresh emulsions. The results obtained in the present work demonstrated that the negatively charged OP-CMC complexes pre-formed by electrostatic interaction contributed to an improved O/W emulsion stability at pH 4.0. The results obtained may be conducive to the potential utilization of OP-based dairy products, especially in an acid environment.