不同超声条件重组油体乳液制备及其稳定性研究

Preparation and Stability of Reconstruction Oil Body Emulsion under Different Ultrasonic Conditions

为构建稳定的重组油体乳液,研究了不同超声功率(200、400 W)和不同超声时间(6、12、24 min)对制备重组油体乳液稳定性的影响。为揭示不同超声条件与重组油体乳液稳定性的关系,采用动态激光散射、激光共聚焦显微镜和圆二色谱,研究了不同超声条件制备的重组油体乳液流体动力学半径、微观结构和Oleosin蛋白的二级结构变化。结果表明,利用超声处理制备的重组油体乳液乳化性、储藏稳定性和界面吸附能力远高于未经超声处理的乳液,并且随着超声时间的延长,乳液粒径逐渐变小,乳滴形状规则、分布均匀,乳液表面负电荷增加;当超声条件为200 W、24 min时,制备的重组油体乳液最为稳定,其乳化活性指数和乳化稳定性指数分别高达652.2 m^2/g和605.2 min;不同超声处理改变了Oleosin蛋白的二级结构,影响其与磷脂酰胆碱的结合能力,进而改变乳液在油水界面吸附特性,证明适宜强度的超声处理有利于重组油体乳液的形成。

Effects of ultrasonic treatments with different powers(200 W,400 W)for different durations(6 min,12 min and 24 min)on the stability of recombinant oil emulsions were investigated.Functional properties of the composite system as a function of ultrasonic conditions were explored at the same time.Circular dichroism spectrum,particle size distribution,ζ-potential,FI and emulsibility were determined.The emulsifying properties of the reconstituted oil body emulsion was significantly increased.At the same time,the volume average particle size was decreased from 1717 nm to 337.5 nm,the absolute value ofζ-potential was increased,and theα-helix content was decreased to 10.4%.And the solution had homogeneous distribution and stable properties.However,with the further increase of ultrasonic power,the surface protein of the recombinant oil body was insoluble,and the functional properties of the recombinant emulsion was decreased.This indicated that the ultrasonic treatment would affect the stability of the recombinant emulsion,and the ultrasonic treatment of suitable strength was beneficial to the formation of the recombinant oil emulsion.