Enhanced survival of probiotics in the electrosprayed microcapsule by addition of fish oil

Abstract

A novel multi-layered microcapsule with lactobacillus plantarum as model probiotics was fabricated using a one-step electrospraying method, which was composed of the core layer (sodium alginate/probiotics/fish oil), the shell layer (sodium alginate/pectin) and the outermost layer (soybean protein isolate coating). Scanning electron microscopy proved that probiotics were encapsulated in the microcapsule and the microcapsule was spherical with smooth surface. The addition of trace fish oil into the microcapsule can not only significantly improve the encapsulation efficiency of probiotics, but also enhance the viability of probiotics when exposure to simulated gastrointestinal (GI) conditions. The survival rate of probiotics in the microcapsule containing fish oil and L. plantarum (SPI–O-L-P) was up to 92.53 ± 0.33% after passing through simulated GI tract. Compared with L. plantarum containing microcapsules, the viability of probiotics in the SPI-O-L-P was significantly enhanced under environmental stresses (heat treatment, storage and freeze-drying). In conclusion, this multi-layered microcapsule system containing trace fish oil presents a great potential in probiotic encapsulation, which is effective to improve the resistant ability of probiotics to adverse conditions. • Multi-layered microcapsule containing probiotics was prepared by coaxial electrospraying. • Addition of fish oil into the microcapsule improved the viability of encapsulated probiotics. • Microcapsulation improved resistance of probiotics to simulated gastrointestinal conditions. • The viability of encapsulated probiotics under environmental stresses was enhanced.