Microencapsulation of an essential oil (cinnamon oil) by spray drying: Effects of wall materials and storage conditions on microcapsule properties

摘要

Microencapsulation of cinnamon essential oil (CEO) by spray drying was carried outto protect it from oxidation and facilitate its application within food products. Wheyprotein isolate (WPI), maltodextrin (MD), and sodium alginate were selected as wallmaterials. Initial experiments were carried out to evaluate the emulsifying capacityand encapsulation efficiency (EE) of the system. The optimum formulation consistedof 70% wall material (WPI: MD: sodium alginate = 1:3:0.01 (w/w)) and 30% CEO. TheEE of the spray-dried CEO microcapsules formed was over 93%, and their retentionduring storage at 50°C for 30 days was over 95%. Gas chromatography and liquidchromatography in conjunction with mass spectrometry were used to identify the reactionproducts formed during oxidation of the CEO and possible oxidation pathwayswere proposed. The optimized formulation identified in this study may be suitablefor the efficiency encapsulation and stabilization of essential oils in powdered form.