【作者】 杨楠； 毛鹏； 张科； 吕瑞鹤； 方亚鹏； Katsuyoshi Nishinari； Glyn O.Phillips；

【Author】 Nan Yang;Peng Mao;Ke Zhang;Ruihe Lv;Yapeng Fang;Katsuyoshi Nishinari;Glyn O.Phillips;Glyn O.Phillips Hydrocolloid Research Centre at HUT, Hubei University of Technology;Hubei Collaborative Innovation Centre for Industrial Fermentation, Hubei University of Technology;

【机构】 湖北工业大学轻工学部食品与制药工程学院菲利普斯亲水胶体研究中心； 湖北工业大学工业发酵协同创新中心；

【摘要】 利用阿拉伯胶(GA)与甜菜果胶(SBP)作为混合乳化剂,以中链甘油三酯(MCT)为油相,制备了一系列不同含油量的水包油(O/W)乳液。通过目测、粒径、油脂浓度和乳液稳定性分析,以及界面张力的测定,研究了乳液的相分离行为及乳液中油脂的迁移规律。研究结果表明,利用4%GA/1%SBP相分离溶液制备的乳液,当含油量>2%时,乳液五相分离,且稳定无粒径变化。当含油量≤2%时,乳液体系出现相分离,上相粒径逐渐增大,下相粒径略有降低,且伴随着相分离现象的发生,油脂出现先朝上相(SBP富集相)再朝下相(GA富集相)运动的迁移规律,最终聚集在两相界面.本文探讨了相分离乳液体系中油脂迁移的机理:粘度效应、GA与SBP间的热力学不相容性及它们在油滴表面的竞争吸附,以及油滴间的排空力是油脂迁移的主要推动力。更多还原

【Abstract】 Oil-in-water(O/W) emulsions with varying oil content of medium-chain triglyceride(MCT), were prepared using gum arabic(GA)/sugar beet pectin(SBP) mixture as an emulsifier. Phase separation of the emulsions and oil migration between separated phases were investigated by means of visual observation, droplet size analysis, oil partition analysis, emulsion stability test and interfacial tension measurement. It was found that in emulsions prepared with 4.0%GA/1.0%SBP, phase separation was not observed when the concentration of MCT was greater than 2.0%, and the emulsions were stable with unchanged droplet size. However, phase separation occurred when the concentration of MCT was equal or less than 2.0%, resulting in upper SBP-rich phase and lower GA-rich phase. The droplet size increased in the upper phase while decreased slightly in the lower phase. During the following storage, the oil droplets exhibited a complex migration process: first moving upward to the SBP-rich phase, then downward to the GA-rich phase and finally gathering at the interface between SBP and GA phases. The mechanism of the oil migration was discussed. Viscosity effect during phase separation, thermodynamic incompatibility between GA and SBP, their competitive adsorption on the droplet surfaces and the depletion force among the droplets in the lower and upper phase were conceived of as the driving forces of oil migration during each stage accordingly.更多还原