荔枝多酚微胶囊的制备工艺优化及其特性分析

Optimization of Preparation Process of Lichi Polyphenols Microcapsules and Its Characteristic Analysis

以海藻酸钠和壳聚糖为壁材,通过复凝聚法制备荔枝多酚微胶囊,提高荔枝多酚的稳定性。选取微胶囊包埋率为优化指标,利用正交试验得出最佳制备工艺,并对微胶囊的体外释放性能、温度稳定性及抗氧化活性进行研究。结果表明,荔枝多酚微胶囊的最佳制备工艺为:海藻酸钠质量分数3.5%,氯化钙质量分数3%,壳聚糖质量分数2.0%,包埋时间1 h,荔枝多酚质量分数0.8%,所得荔枝多酚微胶囊粒径均一,包埋率为95.74%;该微胶囊在模拟肠液(pH6.86)中具有良好的靶向释放性,3 h后多酚释放率为19.66%,ABTS+自由基清除率为20.30%;且在相同的温度条件下,荔枝多酚微胶囊较未包埋的荔枝多酚具有较高的多酚保留率,提高了2.09%~3.34%,表明荔枝多酚的微胶囊化可有效提高荔枝多酚的温度稳定性。

Microcapsules of lichi polyphenols were prepared by complex coacervation method with sodium alginate and chitosan as wall materials, improving the stability of lichi polyphenols. With embedding rate as index, the preparation conditions were optimized by orthogonal experiment, and its in vitro release properties, thermal stability, antioxidant activity were investigated. The results showed that the optimum preparation process of lichi polyphenols was as follows: the mass fraction of sodium alginate, calcium chloride, chitosan and lichi polyphenols were 3.5%, 3%, 2%, 0.8%, embedding time was 1 h. The obtained microcapsules exhibited a uniform particle size and high embedding rate of 95.74%. The microcapsules had great target-releasing behavior in simulated intestinal fluid(pH6.86), the release rate of polyphenols was19.66% and the ABTS+ free radicals scavenging rate was 20.30% at 3 h. Compared with the unembedded lichi polyphenols,the microcapsules had higher polyphenols retention rate at the same condition of temperature(increased by 2.09%~3.34%),which showed that the microcapsulation of lichi polyphenols could effectively improve the thermal stability of lichi polyphenols.