β-环糊精稳定柠檬醛Pickering乳液的制备及其稳定性研究

Preparation of citral emulsion stabilized by β-cyclodextrin and its stability

制备由β-环糊精稳定的高比例柠檬醛相Pickering乳液并研究乳液的稳定特性。利用β-环糊精与柠檬醛的包合物微粒作为乳化稳定剂、通过高速均质法制备柠檬醛的Pickering乳液,观察乳液的微观结构、测定其粒度和Zeta电位,研究体系pH值及添加黄原胶对乳液稳定性的影响,并对其稳定性进行了初步测定。结果表明,柠檬醛-水体系经β-环糊精稳定乳化后可形成稳定的水包油型Pickering乳液,油滴呈标准球形,粒径在数百纳米;偏酸或偏碱性环境条件及添加黄原胶有利于乳液的稳定。进一步研究表明,乳液具有较好的耐热稳定性,但耐冻能力较差,黄原胶的加入(5 g/L)可显著提高乳液的耐冻性。该研究为柠檬醛乳液的绿色制备提供一种新的途径。

This study focuses on the preparation of citral Pickering emulsion stabilized by β-cyclodextrin, the stability of such emulsion and its influence factors. Using nano-particle inclusion complex of β-cyclodextrin with citral as emulsion stablizer, the citral Pickering emulsion was prepared by high-speed homogeneous shearing method. The microstructure of the emulsion was then observed and its particle size and Zeta potential were measured, and the effects of system pH value and xanthan gum on emulsion stability were investigated. The results showed that a stable oil-in-water type Pickering emulsion can be formed by stable emulsification with β-CD, where the oil particle is standard spherical and of several hundred nanometers in particle size. An acidic or alkaline environment, or addition of xanthan gum, was favorable to the stability of the emulsion. Further study indicated that the citral Pickering emulsion showed relative excellent heat stability but poor tolerance of freezing;that adding xanthan gum(5 g/L) could significantly increase the freeze resistance of the emulsion. This research has provided a novel green approach for citral emulsion preparation.