Determination of the Optimum Conditions for Emulsification and Encapsulation of Echium Oil by Response Surface Methodology

Echium oil (EO) contains substantial amounts of omega-3fatty acids,which are important because of their benefits to human health. However,they are prone to oxidation. The aim of this study was to obtain theoptimum conditions of microencapsulation of EO using spray dryingby applying the response surface methodology (RSM). Central compositecircumscribed design (CCC) was employed with a ratio of maltodextrin(MD):EmCap modified starch (MS) (80-90%, w/w), oil concentration(15-25%, w/w), and homogenization speed (5-15 x10(3) rpm) as independent variables affecting droplet size(& mu;m) and viscosity (Pa & BULL;s), which were chosen as responsesfor the emulsification process. The results revealed that the emulsionconditions containing MD:MS (89.7%:10.3%, w/w), oil concentrationof (16.0%), and homogenization speed at (14.8 x 10(3) rpm) were found to be the optimum conditions. Furthermore, for encapsulation,CCC was employed with inlet temperature of 140-180 & DEG;C,air flow of 20-30%, and pump rates of 15-25% as independentvariables. Total yield (%) and encapsulation efficiency (%) were chosenas responses for the encapsulation process. On the other hand, optimumconditions for encapsulation were as follows: inlet temperature of140 & DEG;C, airflow rate of (30%) 0.439 m(3)/h, pump rateof (15%) 4.5 mL/min with respect to selected responses.