Development of oil-loaded alginate-composite microspheres by spray drying

Abstract

The use of alginate-starch blends was investigated for the microencapsulation of fish oils by spray drying. The feasibility of incorporating an in-process particle size analyzer to the spray dryer was also explored. Microspheres containing alginate-starch blends as wall material were produced. It was found that the incorporation of alginate into the wall matrix resulted in the formation of microspheres that were larger, rounder and more resistant to mechanical stress. They could also encapsulate higher oil loads and confer greater protection to the encapsulated oil. The application of an in-process particle size analyzer during spray drying allowed the elucidation of real-time information regarding microsphere size changes during process start-up and shut-down. For highly agglomerated products like the microspheres produced in the present study, an at-line set-up was found to be more useful for the determination of individual microsphere size.