Enhanced viability of probiotics encapsulated within synthetic/natural biopolymers by the addition of gum arabic via electrohydrodynamic processing

Abstract

To enhance the probiotics' viability, novel vehicles consisting of synthetic/natural biopolymers, i.e., polyvinyl alcohol (PVOH), polyvinylpyrrolidone, whey protein concentrate and maltodextrin, encapsulated with L. plantarum KLDS 1.0328 and gum arabic (GA) as a prebiotic were fabricated by electrohydrodynamic techniques. Inclusion of cells into composites caused an increase in conductivity and viscosity. Morphological analysis showed that cells were distributed along the electrospun nanofibres or distributed randomly in the electrosprayed microcapsules. Both intramolecular and intermolecular hydrogen bond interactions exist between biopolymers and cells. Thermal analysis revealed that the degradation temperatures (>300 °C) of various encapsulation systems have potential applications in heat-treatment foods. Additionally, cells especially immobilized in PVOH/GA electrospun nanofibres showed the highest viability compared with free cells after exposure to simulated gastrointestinal stress. Furthermore, cells retained their antimicrobial ability after rehydration of the composite matrices. Therefore, electrohydrodynamic techniques have great potential in encapsulating probiotics.

Keywords: Electrospinning; Electrospraying; Encapsulation; Gum arabic; Lactobacillus.