复凝聚法制备芥末油微胶囊工艺优化及其理化特性分析

Process optimization and physicochemical properties analysis of mustard oil microcapsules prepared by complex coacervation

以明胶和羧甲基纤维素钠为壁材,运用复凝聚法对芥末油进行包埋,利用戊二醛溶液进行固化,经冷冻干燥制成芥末油微胶囊粉末。根据微胶囊包埋率来评价制备工艺,正交优化确定最佳配方,在壁材质量分数为1.5%、壁材比m(明胶)∶m(羧甲基纤维素钠)=10∶1、芯壁比m(芥末油):m(壁材)=1∶1、pH 4.4时所制备的芥末油微胶囊包埋率最高,为86.8%,所得产品水分含量为2.43%,休止角为38.6°,流动性较好。经扫描电镜观察,所得微胶囊表面较光滑,有小部分凹陷。由稳定性试验可知,芥末油微胶囊的氧化稳定性明显高于未包埋的芥末油。红外光谱分析证明了微胶囊的形成,差示扫描量热分析结果显示,包埋后微胶囊的热稳定性提高。

Using gelatin and sodium carboxymethyl cellulose as wall materials,the mustard oil was embedded by coacervation method,and then was solidified with glutaraldehyde solution and freeze-dried to prepare mustard oil microcapsule powder.The preparation process was evaluated according to the microcapsule embedding rate.The optimal formulation was determined by orthogonal test.The results showed that when the mass fraction of wall material was 1.5%,the ratio of wall material m(gelatin)∶m(sodium carboxymethyl cellulose)=10∶1,core wall ratio m(mustard oil)∶m(wall material)=1∶1,and the pH was 4.5,the prepared mustard oil microcapsule had the highest embedding rate which was 85.4%.The resulting product had a moisture content of 2.43%,an angle of repose of 38.3°,and had good fluidity.Scanning electron microscope(SEM)showed that the obtained microcapsules had a smooth surface and a small part of depressions.The stability test showed that the oxidative stability of the mustard oil microcapsules was significantly higher than that of the unembedded mustard oil.The formation of microcapsules was confirmed by infrared spectrum analysis,and the thermal stability of microcapsules was improved by differential scanning calorimetry.