Microencapsulation of oregano essential oil by spray-drying using maltodextrin: gum arabic blends

Abstract

The effect of processing parameters on microencapsulation of oregano essential with maltodextrin:gum arabic using a disk atomiser spray-dryer was evaluated. By means of response surface methodology, the feed flow rate and inlet air temperature were optimised. Powder yield, moisture content, essential oil retention, and antioxidant activity of microparticles were evaluated. The best conditions to produce microencapsulated oregano essential oil were 0.6 L h−1 for feed flow rate and 200 °C for inlet air temperature. With this combination a microencapsulated powder with 89.8% powder yield, 2.1% moisture content, 92.1% essential oil retention, 76 s solubilisation time, 12.9 g of water/100 g of dry matter, 0.3371 g mL−1 bulk density, 0.5826 g mL−1 tapped density, and 8.2 μm of average particle size was produced. The microencapsulation of oregano essential oil preserves the antioxidant and antimicrobial activities of its bioactive compounds.