The effect of some technological factors on the efficiency of microencapsulation of lemongrass essential oil by the spray drying method

Abstract

   In this study, the microencapsulation of the lemongrass essential oil was successfully carried out by the spray drying method. A number of technological factors were surveyed to assess the quality of powder products including: the effect of the concentration of wall material, of the ratio and type of wall material, and that of the concentration of essential oils. The properties of powder products were evaluated through microencapsulation yield (MEY), microencapsulation efficiency (MEE) and surface oil (SO) content. Maltodextrin was chosen as the wall material because of its good properties in water solubility and its ability to store active substances inside. The survey results have shown that at wall material concentration of 30% (w/w) and the concentration of the essential oils of 1.5% (w/v), the microencapsulation yield was the highest at 89.31%. The gas chromatography-mass spectrometry (GC-MS) indicated that the main components of lemongrass oil; Citral (Z-Citral and E-Citral) were retained with high concentration after the spray drying process. In addition, the result of the SEM images displayed particles‟ size of 1m. This proves that the lemongrass oil, which contains a large amount of Citral, was well protected by spray drying method with micro size.