Condition optimization for thyme oil microcapsules prepared by layer-by-layer self-assembly method

In this work, using thyme oil emulsion nanoparticles as the core, chitosan (CS) and sodium alginate (ALG) were employed for embedding thyme essential oil by a layer-by-layer self-assembly method. Three emulsification conditions including HLB (hydrophilic lipophilic balance) value of 1:1 mixture of Span 80 and Tween 60, emulsifier concentration and ratio of oil to emulsifier were optimized to be 10, 6% and 1:6, respectively. The maximum microencapsulation efficiency of 80.23% was obtained when self-assembly of the emulsion particles in four layers by alternate use of CS and ALG was conducted for 15 min at 30 ℃ with stirring at a speed of 1 040 r/min, as determined by orthogonal array design. © 2016, China Food Publishing Company. All right reserved.