磷脂微胶囊化乳化液稳定性的研究

Stability of Emulsion during Encapsulation of Lecithin

本文主要研究磷脂微胶囊化过程中乳化液稳定性的影响因素、乳化液稳定性表征及磷脂微胶囊化乳化液制备条件。随着乳化液中干物质浓度增加,乳化液稳定性增强,浓度超过35%时稳定性减弱;干物质浓度与乳化液黏度呈指数关系。芯材(磷脂)含量低于70%时,芯材含量的变化对乳化液稳定性影响不显著。乳化温度的升高有利于乳化稳定性。均质时间的延长和压力的增加都会增强乳化稳定性,但乳化时间超过10 min,压力超过45 MPa后,均质条件的变化对乳化稳定性的作用甚小。试验结果证明:乳化液微粒大小、黏度、电导率、吸光度能有效表征磷脂微胶囊化乳化液的稳定性。磷脂微胶囊化稳定乳化液的制备条件:干物质含量30%,乳化温度40℃,芯材(磷脂)含量60%,乳化温度40℃,均质压力45 MPa,均质时间10 min,乳化剂为吐温与司班的混合物(HLB 8),乳化剂添加量0.1%。

This work is aimed to investigate the factors affecting the stability of lecithin-microencapsulted emulsion to feed spray-drying,the indices expressing the stability of emulsion,and the parameters for preparing stable emulsion.Results： The stability of the emulsion is enhanced with increasing the solid concentration of emulsion,but is reduced when the concentration is 〉35%.The effect of solid concentration on the viscosity could be described by an exponential.In the range of 0～70%,increasing the core（lecithin） content does not significantly affect the stability.Increasing the emulsification temperature is beneficial to the stability.Long time and high pressure for the homogenization increase the stability,but the change of homogenization conditions produces little effect on the stability at homogenization time 〉 11min and pressure 〉45MPa.It is proved that the indices for droplet size,viscosity,conductivity and absorbency well represent the stability of the emulsion,respectively.A fine stable emulsion is available at the following emulsion conditions： solid concentration 30%,emulsification temperature 40 ℃,core（lecithin） content 60%,homogenization time 10 min,pressure 45MPa,using mixture of Tween and Span（HLB 8） as emulsifier,and emulsifier dose 0.1%.