薄荷油纳米乳液消化规律与稳定性研究

研究了薄荷油纳米乳液在体外模拟消化过程中乳液包埋对其平均粒径、ζ-电位、游离脂肪酸释放率以及薄荷醇生物可利用度的影响。激光扫描3D共聚焦显微镜观察薄荷油纳米乳液的显微结构,研究发现薄荷油完全被SPI包埋,纳米乳液液滴呈球状形态,表明大豆蛋白完整地吸附于纳米乳液的油-水界面处,呈现出核壳状结构。高压均质处理制备的薄荷油纳米乳液的游离脂肪酸释放率及薄荷醇生物可利用度远大于薄荷油的对照组。薄荷油纳米乳液在模拟胃消化阶段,乳液的平均粒径、ζ-电位均变大,乳液的微观结构表明消化体系出现液滴聚合现象;在模拟肠液消化后,薄荷油纳米乳液的界面蛋白被水解,油滴被消化,乳液的平均粒径减小、ζ-电位绝对值增加。通过多重光散射稳定性分析仪检测薄荷油纳米乳液的稳定性,薄荷油稳定性指数为2.8,且检测过程中并未出现乳液上浮和絮凝等现象。

Investigation on Digestion Law and Stability of Peppermint Oil Nanoemulsion

Investigation was made on the effects of the peppermint oil nanoemulsion on the average particle size, zeta potential, turbidity, FFA release rate and the bioavailability of menthol in vitro simulated digestion process. It was found that peppermint oil was completely packed by SPI and nanoemulsion droplet was in the spherical shape by using confocal laser scanning 3D microscopy to observe the microstructure of peppermint oil nanoemulsion, indicating that the soybean protein was completely adsorbed at the oil-water interface of the nanoemulsion and presented a core shell structure. The results indicated that the FFA release rate and menthol bioavailability of the peppermint oil nanoemulsion prepared by high-pressure-homogenization were much higher than that in the control group of peppermint oil. In the simulated gastric digestion phase, the average particle size and the zeta potential of the nanoemulsion were increased, while the turbidity was decreased and the microstructure of the digestive emulsion showed the phenomenon of droplet polymerization. After the simulated intestinal juice was digested, the interfacial protein of peppermint oil nanoemulsion was hydrolyzed, the oil droplets were digested, the average particle size of the emulsion was decreased, and the absolute value of zeta-potential was increased. The stability of the peppermint oil nanoemulsion was checked by the Turbiscan stability analyzer, and the stability index was found to be 2.8. There was no emulsion floatation and flocculation occurred during the test.