Scale-up of layer-by-layer microencapsulation and freeze-drying of probiotic bacteria

Abstract

Layer-by-layer (LbL) self-assembly microencapsulation is a promising method to protect and deliver probiotics, although its implementation has mostly been confined to the lab scale. This study develops a scalable method for encapsulating probiotics by LbL, targeting their release in the gut. Chitosan and alginate were used as layering biopolymers, while Lactiplantibacillus plantarum WCFS1 was the encapsulated probiotic. Variables such as chitosan dilution (first layer), number of layers, and biomass concentration were targeted. Freeze-drying with fructooligosaccharides (FOS) and maltodextrin were used to stabilize encapsulated bacteria. Microbiological and structural characterization of dehydrated cells was performed.