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

Microencapsulation of cinnamon essential oil (CEO) by spray drying was carried out to protect it from oxidation and facilitate its application within food products. Whey protein isolate (WPI), maltodextrin (MD), and sodium alginate were selected as wall materials. Initial experiments were carried out to evaluate the emulsifying capacity and encapsulation efficiency (EE) of the system. The optimum formulation consisted of 70% wall material (WPI: MD: sodium alginate = 1:3:0.01 (w/w)) and 30% CEO. The EE of the spray-dried CEO microcapsules formed was over 93%, and their retention during storage at 50°C for 30 days was over 95%. Gas chromatography and liquid chromatography in conjunction with mass spectrometry were used to identify the reaction products formed during oxidation of the CEO and possible oxidation pathways were proposed. The optimized formulation identified in this study may be suitable for the efficiency encapsulation and stabilization of essential oils in powdered form. Practical applications The optimized spray drying formulation can be applicated in processing essential oil to improve their storage stability. The spray-dried product in this study can be utilized in meat preservation and pastry (or biscuit) processing as food additives.