Ascorbic acid encapsulation in a glassy carbohydrate matrix via hot melt extrusion: Preparation and characterization

Abstract Hot melt extrusion technology using a twin-screw extruder was employed to obtain maltodextrin, maltodextrin-gum arabic and maltodextrin-trehalose based glassy extrudates containing ascorbic acid (dispersed phase). Ascorbic acid payload of all three formulations was more than 15.67 g/100 g extrudates while the ascorbic acid yield was above 97%. The glass transition temperature (Tg) of all extrudates was above 40 °C. The expansion ratio of the extrudates and Tg reduced due to the incorporation of trehalose and gum arabic to maltodextrins, respectively. The results of Scanning Electron Microscopy, X-ray diffraction and Fourier-transform Infrared Spectroscopy confirmed that the formulated feed material turned into a glassy state, whereas, ascorbic acid was uniformly dispersed throughout the glassy matrix. Extruded formulations showed a steady dissolution rate, therefore, having a role in controlling the dissolution rate of ascorbic acid.

摘要：本研究采用双螺杆挤出机（twin-screw extruder）的热熔挤出技术（hot melt extrusion technology），制备了以麦芽糊精（maltodextrin）、麦芽糊精-阿拉伯胶（gum arabic）及麦芽糊精-海藻糖（trehalose）为基质的玻璃态挤出物，体系中包埋有作为分散相的抗坏血酸（ascorbic acid）。三种配方的抗坏血酸载药量均超过15.67 g/100 g挤出物，且抗坏血酸得率高于97%。所有挤出物的玻璃化转变温度（glass transition temperature, Tg）均高于40℃。分别向麦芽糊精基质中添加海藻糖与阿拉伯胶后，挤出物的膨胀率与玻璃化转变温度均出现下降。扫描电子显微镜（Scanning Electron Microscopy, SEM）、X射线衍射（X-ray Diffraction, XRD）与傅里叶变换红外光谱（Fourier-transform Infrared Spectroscopy, FTIR）的表征结果证实，所配制的进料物料可转变为玻璃态，且抗坏血酸均匀分散于整个玻璃态基质中。该挤出配方展现出稳定的溶出速率，可用于调控抗坏血酸的溶出行为。