紫苏α- 亚麻酸乙酯微囊粉的制备及结构表征

Synthesis and Structural Characterization of Perilla α-Ethyl Linolenate Microcapsule Powder

摘要:

为提高紫苏α-亚麻酸的贮藏稳定性，该研究使用麦芽糊精（MD）和大豆分离蛋白（SPI）为壁材，制备紫苏α-亚麻酸乙酯（AEL）微囊粉，通过单因素试验与响应面分析对微囊粉制备工艺条件进行优化，并通过扫描电子显微镜、激光粒度仪、傅里叶变换红外光谱、X射线衍射、热重分析对其理化性质进行表征。结果表明，AEL微囊粉最佳制备工艺条件为：固形物质量分数10%、壁材比2:5、芯壁比2:5、乳化温度50.7 ℃、均质时间6 min，所得微囊粉包埋率为81.68%。理化性质分析表明，AEL被成功包埋于微囊粉壁壳之中，AEL微囊粉呈球形，囊壁无裂缝和孔隙；AEL微囊粉失重率为76.00%，热稳定性提高。模拟胃液消化后，微囊粉芯材释放率为15.23%；模拟肠液消化后，微囊粉芯材释放率为80.02%，具有良好的缓释效果。氧化稳定性试验表明微胶囊化技术有效延缓了AEL的氧化进程。该方法能够成功包埋AEL，并提高紫苏α-亚麻酸的稳定性，为紫苏α-亚麻酸在食品及保健品领域的深度开发与应用奠定基础。

Abstract:

To enhance the storage stability of α-linolenic acid derived from Perilla frutescens, maltodextrin and soy protein isolate were employed as wall materials to prepare perilla α-ethyl linolenate (AEL) microcapsule powder. The preparation conditions were optimized using single-factor experiments combined with response surface methodology. The physicochemical properties of the resulting microcapsule powder were characterized by scanning electron microscopy, laser particle size analysis, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. Results revealed that the optimal preparation conditions for the AEL microcapsule powder were as follows: mass fraction of solids=10%, wall material ratio=2:5, core-to-wall ratio=2:5, emulsification temperature=50.7 ℃, and homogenization time=6 min. Under these conditions, the encapsulation efficiency reached 81.68% in the microcapsule powder. Physicochemical analysis confirmed the successful encapsulation of AEL within the microcapsule shell. The AEL microcapsule powder exhibited a spherical morphology with no visible cracks or pores, a weight loss rate of 76.00%, and improved thermal stability. The core material release rate of the microcapsule powder was 15.23% after simulated gastric digestion and 80.02% after simulated intestinal digestion, indicating a favorable controlled-release profile. Oxidative stability testing further revealed that microencapsulation effectively delayed AEL oxidation. Overall, this approach successfully encapsulated AEL and enhanced the stability of perilla α-linolenic acid, thereby laying the foundation for its in-depth development and application in the food and nutraceutical industries.