Enhancing the survival of Lactobacillus plantarum via the rational design of whey protein isolate-high acyl gellan gum gelled water-in-oil emulsions

Abstract

In the present study, single whey protein isolate (WPI) gel, high acyl gellan gum (HG), and WPI-HG composite gels at various WPI concentrations in the water phase within W/O emulsions were prepared, to explore the effects of different gel structures on the stability of the emulsion system and the survival of encapsulated Lactobacillus plantarum. The results indicated that the WPI-HG composite gel had a superior effect to the single WPI or HG gel in the stabilization of the W/O emulsion, because of the decrease in droplet size and increase in viscoelasticity. When the WPI concentration was greater than 4.0 wt%, the WPI-HG gel in the internal aqueous phase contributed to a tremendous improvement in the survival rate of Lactobacillus plantarum during the 6-month storage period. The strengthened network structure and lower water activity in the composite gel help improve the probiotics the viability against the thermal damage and harsh gastrointestinal conditions.